NEWS revision 1.16
1 This file contains information about GCC releases which has been generated 2 automatically from the online release notes. It covers releases of GCC 3 (and the former EGCS project) since EGCS 1.0, on the line of development 4 that led to GCC 3. For information on GCC 2.8.1 and older releases of GCC 2, 5 see ONEWS. 6 7 ====================================================================== 8 http://gcc.gnu.org/gcc-10/index.html 9 10 GCC 10 Release Series 11 12 July, 7, 2023 13 14 The [1]GNU project and the GCC developers are pleased to announce the 15 release of GCC 10.5. 16 17 This release is a bug-fix release, containing fixes for regressions in 18 GCC 10.4 relative to previous releases of GCC. 19 20 Release History 21 22 GCC 10.5 23 July 7, 2023 ([2]changes, [3]documentation) 24 25 GCC 10.4 26 June 28, 2022 ([4]changes, [5]documentation) 27 28 GCC 10.3 29 April 8, 2021 ([6]changes, [7]documentation) 30 31 GCC 10.2 32 July 23, 2020 ([8]changes, [9]documentation) 33 34 GCC 10.1 35 May 7, 2020 ([10]changes, [11]documentation) 36 37 References and Acknowledgements 38 39 GCC used to stand for the GNU C Compiler, but since the compiler 40 supports several other languages aside from C, it now stands for the 41 GNU Compiler Collection. 42 43 A list of [12]successful builds is updated as new information becomes 44 available. 45 46 The GCC developers would like to thank the numerous people that have 47 contributed new features, improvements, bug fixes, and other changes as 48 well as test results to GCC. This [13]amazing group of volunteers is 49 what makes GCC successful. 50 51 For additional information about GCC please refer to the [14]GCC 52 project web site or contact the [15]GCC development mailing list. 53 54 To obtain GCC please use [16]our mirror sites or [17]our version 55 control system. 56 57 58 For questions related to the use of GCC, please consult these web 59 pages and the [18]GCC manuals. If that fails, the 60 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 61 web pages and the development of GCC are welcome on our developer 62 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 63 archives. 64 65 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 66 distribution of this entire article is permitted in any medium, 67 provided this notice is preserved. 68 69 These pages are [23]maintained by the GCC team. Last modified 70 2023-07-07. 71 72 References 73 74 1. http://www.gnu.org/ 75 2. http://gcc.gnu.org/gcc-10/changes.html 76 3. http://gcc.gnu.org/onlinedocs/10.5.0/ 77 4. http://gcc.gnu.org/gcc-10/changes.html 78 5. http://gcc.gnu.org/onlinedocs/10.4.0/ 79 6. http://gcc.gnu.org/gcc-10/changes.html 80 7. http://gcc.gnu.org/onlinedocs/10.3.0/ 81 8. http://gcc.gnu.org/gcc-10/changes.html 82 9. http://gcc.gnu.org/onlinedocs/10.2.0/ 83 10. http://gcc.gnu.org/gcc-10/changes.html 84 11. http://gcc.gnu.org/onlinedocs/10.1.0/ 85 12. http://gcc.gnu.org/gcc-10/buildstat.html 86 13. http://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Contributors.html 87 14. http://gcc.gnu.org/index.html 88 15. mailto:gcc (a] gcc.gnu.org 89 16. http://gcc.gnu.org/mirrors.html 90 17. http://gcc.gnu.org/git.html 91 18. https://gcc.gnu.org/onlinedocs/ 92 19. mailto:gcc-help (a] gcc.gnu.org 93 20. mailto:gcc (a] gcc.gnu.org 94 21. https://gcc.gnu.org/lists.html 95 22. https://www.fsf.org/ 96 23. https://gcc.gnu.org/about.html 97 ====================================================================== 98 http://gcc.gnu.org/gcc-10/changes.html 99 100 GCC 10 Release Series 101 Changes, New Features, and Fixes 102 103 This page is a "brief" summary of some of the huge number of 104 improvements in GCC 10. You may also want to check out our [1]Porting 105 to GCC 10 page and the [2]full GCC documentation. 106 107 Caveats 108 109 * An ABI incompatibility between C++14 and C++17 has been fixed. On 110 some targets a class with a zero-sized subobject would be passed 111 incorrectly when compiled as C++17 or C++20. See the [3]C++ notes 112 below for more details. 113 * The deprecated Profile Mode and array_allocator extensions have 114 been removed from libstdc++. 115 * The non-standard std::__is_nullptr_t type trait is deprecated and 116 will be removed from libstdc++ in a future release. The standard 117 trait std::is_null_pointer should be instead. 118 * The minimum version of the [4]MPFR library required for building 119 GCC has been increased to version 3.1.0 (released 2011-10-03). 120 * The automatic template instantiation at link time (-frepo) has been 121 removed. 122 * The --param allow-store-data-races internal parameter has been 123 removed in favor of a new official option -fallow-store-data-races. 124 While default behavior is unchanged and the new option allows to 125 correctly maintain a per compilation unit setting across link-time 126 optimization, alteration of the default via --param 127 allow-store-data-races will now be diagnosed and build systems have 128 to be adjusted accordingly. 129 * Offloading to Heterogeneous System Architecture Intermediate 130 Language (HSAIL) has been deprecated and will likely be removed in 131 a future release. 132 * The type of the std::iterator base class of 133 std::istreambuf_iterator was changed in C++98 mode to be consistent 134 with C++11 and later standards. See the [5]libstdc++ notes below 135 for more details. 136 137 General Improvements 138 139 * New built-in functions: 140 + The [6]__has_builtin built-in preprocessor operator can be 141 used to query support for built-in functions provided by GCC 142 and other compilers that support it. 143 + __builtin_roundeven for the corresponding function from 144 ISO/IEC TS 18661. 145 * New command-line options: 146 + [7]-fallocation-dce removes unneeded pairs of new and delete 147 operators. 148 + [8]-fprofile-partial-training can now be used to inform the 149 compiler that code paths not covered by the training run 150 should not be optimized for size. 151 + [9]-fprofile-reproducible controls level of reproducibility of 152 profile gathered by [10]-fprofile-generate. This makes it 153 possible to rebuild program with same outcome which is useful, 154 for example, for distribution packages. 155 + [11]-fprofile-prefix-path can be used in combination with 156 -fprofile-generate=profile_dir and -fprofile-use=profile_dir 157 to inform GCC where the base directory of build source tree is 158 in case it differs between instrumentation and optimized 159 builds. 160 + [12]-fanalyzer enables a new static analysis pass and 161 associated warnings. This pass performs a time-consuming 162 exploration of paths through the code in the hope of detecting 163 various common errors, such as double-free bugs. This option 164 should be regarded as experimental in this release. In 165 particular, analysis of non-C code is unlikely to work. 166 * Inter-procedural optimization improvements: 167 + The inter-procedural scalar replacement of aggregates 168 (IPA-SRA) pass was re-implemented to work at link-time and can 169 now also remove computing and returning unused return values. 170 + [13]-finline-functions is now enabled at -O2 and was retuned 171 for better code size versus runtime performance trade-offs. 172 Inliner heuristics was also significantly sped up to avoid 173 negative impact to -flto -O2 compile times. 174 + Inliner heuristics and function cloning can now use 175 value-range information to predict effectivity of individual 176 transformations. 177 + During link-time optimization the C++ One Definition Rule is 178 used to increase precision of type based alias analysis. 179 * Link-time optimization improvements: 180 + A new binary [14]lto-dump has been added. It dumps various 181 information about LTO bytecode object files. 182 + The parallel phase of the LTO can automatically detect a 183 running make's jobserver or fall back to number of available 184 cores. 185 + The LTO bytecode can be compressed with the [15]zstd 186 algorithm. The configure script automatically detects zstd 187 support. 188 + Most --param values can now be specified at translation unit 189 granularity. This includes all parameters controlling the 190 inliner and other inter-procedural optimizations. Unlike 191 earlier releases, GCC 10 will ignore parameters controlling 192 optimizations specified at link-time and apply parameters 193 specified at compile-time in the same manner as done for 194 optimization flags. 195 * Profile driven optimization improvements: 196 + Profile maintenance during compilation and hot/cold code 197 partitioning have been improved. 198 + Using [16]-fprofile-values, an instrumented binary can track 199 multiple values (up to 4) for e.g. indirect calls and provide 200 more precise profile information. 201 202 New Languages and Language-Specific Improvements 203 204 * Version 2.6 of the [17]OpenACC specification is now supported by 205 the C, C++ and Fortran compilers. See the [18]implementation status 206 section on the OpenACC wiki page and the [19]run-time library 207 documentation for further information. 208 * GCC 10 adds a number of newly implemented [20]OpenMP 5.0 features 209 such as conditional lastprivate clause, scan and loop directives, 210 order(concurrent) and use_device_addr clauses support, if clause on 211 simd construct, and partial support for the declare variant 212 directive, getting closer to full support of the OpenMP 5.0 213 standard. 214 * OpenMP and OpenACC now support [21]offloading to AMD Radeon (GCN) 215 GPUs; supported are the third-generation Fiji (fiji) and the 216 fifth-generation VEGA 10/VEGA 20 (gfx900 or gfx906). 217 218 C family 219 220 * New attributes: 221 + The access function and type attribute has been added to 222 describe how a function accesses objects passed to it by 223 pointer or reference, and to associate such arguments with 224 integer arguments denoting the objects' sizes. The attribute 225 is used to enable the detection of invalid accesses by 226 user-defined functions, such as those diagnosed by 227 -Wstringop-overflow. 228 + The symver attribute can be used to bind symbols to specific 229 version nodes on ELF platforms. This is preferred to using 230 inline assembly with GNU as symver directive because the 231 latter is not compatible with link-time optimizations. 232 * New warnings: 233 + [22]-Wstring-compare, enabled by -Wextra, warns about equality 234 and inequality expressions between zero and the result of a 235 call to either strcmp and strncmp that evaluate to a constant 236 as a result of the length of one argument being greater than 237 the size of the array pointed to by the other. 238 + [23]-Wzero-length-bounds, enabled by -Warray-bounds, warns 239 about accesses to elements of zero-length arrays that might 240 overlap other members of the same object. 241 * Enhancements to existing warnings: 242 + [24]-Warray-bounds detects more out-of-bounds accesses to 243 member arrays as well as accesses to elements of zero-length 244 arrays. 245 + [25]-Wformat-overflow makes full use of string length 246 information computed by the strlen optimization pass. 247 + [26]-Wrestrict detects overlapping accesses to dynamically 248 allocated objects. 249 + [27]-Wreturn-local-addr diagnoses more instances of return 250 statements returning addresses of automatic variables. 251 + [28]-Wstringop-overflow detects more out-of-bounds stores to 252 member arrays including zero-length arrays, dynamically 253 allocated objects and variable length arrays, as well as more 254 instances of reads of unterminated character arrays by string 255 built-in functions. The warning also detects out-of-bounds 256 accesses by calls to user-defined functions declared with the 257 new attribute access. 258 + [29]-Warith-conversion re-enables warnings from -Wconversion, 259 -Wfloat-conversion, and -Wsign-conversion that are now off by 260 default for an expression where the result of an arithmetic 261 operation will not fit in the target type due to promotion, 262 but the operands of the expression do fit in the target type. 263 * Extended characters in identifiers may now be specified directly in 264 the input encoding (UTF-8, by default), in addition to the UCN 265 syntax (\uNNNN or \UNNNNNNNN) that is already supported: 266 267 static const int p = 3; 268 int get_nave_pi() { 269 return p; 270 } 271 272 C 273 274 * Several new features from the upcoming C2X revision of the ISO C 275 standard are supported with -std=c2x and -std=gnu2x. Some of these 276 features are also supported as extensions when compiling for older 277 language versions. In addition to the features listed, some 278 features previously supported as extensions and now added to the C 279 standard are enabled by default in C2X mode and not diagnosed with 280 -std=c2x -Wpedantic. 281 + The [[]] attribute syntax is supported, as in C++. Existing 282 attributes can be used with this syntax in forms such as 283 [[gnu::const]]. The standard attributes [[deprecated]], 284 [[fallthrough]] and [[maybe_unused]] are supported. 285 + UTF-8 character constants using the u8'' syntax are supported. 286 + <float.h> defines macros FLT_NORM_MAX, DBL_NORM_MAX and 287 LDBL_NORM_MAX. 288 + When decimal floating-point arithmetic is supported, <float.h> 289 defines macros DEC32_TRUE_MIN, DEC64_TRUE_MIN and 290 DEC128_TRUE_MIN, in addition to the macros that were 291 previously only defined if __STDC_WANT_DEC_FP__ was defined 292 before including <float.h>. 293 + In C2X mode, empty parentheses in a function definition give 294 that function a type with a prototype for subsequent calls; 295 other old-style function definitions are diagnosed by default 296 in C2X mode. 297 + The strftime format checking supports the %OB and %Ob formats. 298 + In C2X mode, -fno-fp-int-builtin-inexact is enabled by 299 default. 300 * GCC now defaults to -fno-common. As a result, global variable 301 accesses are more efficient on various targets. In C, global 302 variables with multiple tentative definitions now result in linker 303 errors. With -fcommon such definitions are silently merged during 304 linking. 305 306 C++ 307 308 * Several C++20 features have been implemented: 309 + Concepts, including P0734R0, P0857R0, P1084R2, P1141R2, 310 P0848R3, P1616R1, P1452R2 311 + P1668R1, Permitting Unevaluated inline-assembly in constexpr 312 Functions 313 + P1161R3, Deprecate a[b,c] 314 + P0848R3, Conditionally Trivial Special Member Functions 315 + P1091R3, Extending structured bindings 316 + P1143R2, Adding the constinit keyword 317 + P1152R4, Deprecating volatile 318 + P0388R4, Permit conversions to arrays of unknown bound 319 + P0784R7, constexpr new 320 + P1301R4, [[nodiscard("with reason")]] 321 + P1814R0, class template argument deduction for alias templates 322 + P1816R0, class template argument deduction for aggregates 323 + P0960R3, Parenthesized initialization of aggregates 324 + P1331R2, Allow trivial default initialization in constexpr 325 contexts 326 + P1327R1, Allowing dynamic_cast and polymorphic typeid in 327 constexpr contexts 328 + P0912R5, Coroutines (requires -fcoroutines) 329 * Several C++ Defect Reports have been resolved, e.g.: 330 + DR 1560, lvalue-to-rvalue conversion in ?: 331 + DR 1813, __is_standard_layout for a class with repeated bases 332 + DR 2094, volatile scalars are trivially copyable, 333 + DR 2096, constraints on literal unions 334 + DR 2413, typename in conversion-function-ids 335 + DR 2352, Similar types and reference binding 336 + DR 1601, Promotion of enumeration with fixed underlying type 337 + DR 330, Qualification conversions and pointers to arrays of 338 pointers 339 + DR 1307, Overload resolution based on size of array 340 initializer-list 341 + DR 1710, Missing template keyword in class-or-decltype 342 * New warnings: 343 + [30]-Wmismatched-tags, disabled by default, warns about 344 declarations of structs, classes, and class templates and 345 their specializations with a class-key that does not match 346 either the definition or the first declaration if no 347 definition is provided. The option is provided to ease 348 portability to Windows-based compilers. 349 + [31]-Wredundant-tags, disabled by default, warns about 350 redundant class-key and enum-key in contexts where the key can 351 be eliminated without causing an syntactic ambiguity. 352 * G++ can now detect modifying constant objects in constexpr 353 evaluation (which is undefined behavior). 354 * G++ no longer emits bogus -Wsign-conversion warnings with explicit 355 casts. 356 * Narrowing is now detected in more contexts (e.g., case values). 357 * Memory consumption of the compiler has been reduced in constexpr 358 evaluation. 359 * The noexcept-specifier is now properly treated as a complete-class 360 context as per [class.mem]. 361 * The attribute deprecated can now be used on namespaces too. 362 * The ABI of passing and returning certain C++ classes by value 363 changed on several targets in GCC 10, including [32]AArch64, 364 [33]ARM, [34]PowerPC ELFv2, [35]S/390 and [36]Itanium. These 365 changes affect classes with a zero-sized subobject (an empty base 366 class, or data member with the [[no_unique_address]] attribute) 367 where all other non-static data members have the same type (this is 368 called a "homogeneous aggregate" in some ABI specifications, or if 369 there is only one such member, a "single element"). In -std=c++17 370 and -std=c++20 modes, classes with an empty base class were not 371 considered to have a single element or to be a homogeneous 372 aggregate, and so could be passed differently (in the wrong 373 registers or at the wrong stack address). This could make code 374 compiled with -std=c++17 and -std=c++14 ABI incompatible. This has 375 been corrected and the empty bases are ignored in those ABI 376 decisions, so functions compiled with -std=c++14 and -std=c++17 are 377 now ABI compatible again. Example: struct empty {}; struct S : 378 empty { float f; }; void f(S);. Similarly, in classes containing 379 non-static data members with empty class types using the C++20 380 [[no_unique_address]] attribute, those members weren't ignored in 381 the ABI argument passing decisions as they should be. Both of these 382 ABI changes are now diagnosed with -Wpsabi. 383 384 Runtime Library (libstdc++) 385 386 * Improved experimental C++2a support, including: 387 + Library concepts in <concepts> and <iterator>. 388 + Constrained algorithms in <ranges>, <algorithm>, and <memory> 389 (thanks to Patrick Palka). 390 + New algorithms shift_left and shift_right (thanks to Patrick 391 Palka). 392 + std::span (thanks to JeanHeyd Meneide). 393 + Three-way comparisons in <compare> and throughout the library. 394 + Constexpr support in <algorithm> and elsewhere (thanks to 395 Edward Smith-Rowland). 396 + <stop_token> and std::jthread (thanks to Thomas Rodgers). 397 + std::atomic_ref and std::atomic<floating point>. 398 + Integer comparison functions (cmp_equal, cmp_less etc.). 399 + std::ssize, std::to_array. 400 + std::construct_at, std::destroy, constexpr std::allocator. 401 + Mathematical constants in <numbers>. 402 * Support for RDSEED in std::random_device. 403 * Reduced header dependencies, leading to faster compilation for some 404 code. 405 * The std::iterator base class of std::istreambuf_iterator was 406 changed in C++98 mode to be consistent with C++11 and later 407 standards. This is expected to have no noticeable effect except in 408 the unlikely case of a class which has potentially overlapping 409 subobjects of type std::istreambuf_iterator<C> and another iterator 410 type with a std::iterator<input_iterator_tag, C, ...> base class. 411 The layout of such a type might change when compiled as C++98. 412 [37]Bug 92285 has more details and concrete examples. 413 414 D 415 416 * Support for static foreach has been implemented. 417 * Aliases can now be created directly from any __traits that return 418 symbols or tuples. Previously, an AliasSeq was necessary in order 419 to alias their return. 420 * It is now possible to detect the language ABI specified for a 421 struct, class, or interface using __traits(getLinkage, ...). 422 * Support for core.math.toPrec intrinsics has been added. These 423 intrinsics guarantee the rounding to specific floating-point 424 precisions at specified points in the code. 425 * Support for pragma(inline) has been implemented. Previously the 426 pragma was recognized, but had no effect on the compilation. 427 * Optional parentheses in asm operands are deprecated and will be 428 removed in a future release. 429 * All content imported files are now included in the make dependency 430 list when compiling with -M. 431 * Compiler recognized attributes provided by the gcc.attribute module 432 will now take effect when applied to function prototypes as well as 433 when applied to full function declarations. 434 * Added a --enable-libphobos-checking configure option to control 435 whether run-time checks are compiled into the D runtime library. 436 * Added a --with-libphobos-druntime-only configure option to indicate 437 whether to build only the core D runtime library, or both the core 438 and standard libraries into libphobos. 439 440 Fortran 441 442 * use_device_addr of version 5.0 of the [38]OpenMP specification is 443 now supported. Note that otherwise OpenMP 4.5 is partially 444 supported in the Fortran compiler; the largest missing item is 445 structure element mapping. 446 * The default buffer size for I/O using unformatted files has been 447 increased to 1048576. The buffer size for can now be set at runtime 448 via the environment variables GFORTRAN_FORMATTED_BUFFER_SIZE and 449 GFORTRAN_UNFORMATTED_BUFFER_SIZE for formatted and unformatted 450 files, respectively. 451 * Mismatches between actual and dummy argument lists in a single file 452 are now rejected with an error. Use the new option 453 -fallow-argument-mismatch to turn these errors into warnings; this 454 option is implied with -std=legacy. -Wargument-mismatch has been 455 removed. 456 * The handling of a BOZ literal constant has been reworked to provide 457 better conformance to the Fortran 2008 and 2018 standards. In these 458 Fortran standards, a BOZ literal constant is a typeless and 459 kindless entity. As a part of the rework, documented and 460 undocumented extensions to the Fortran standard now emit errors 461 during compilation. Some of these extensions are permitted with the 462 -fallow-invalid-boz option, which degrades the error to a warning 463 and the code is compiled as with older gfortran. 464 * At any optimization level except-Os, gfortran now uses inline 465 packing for arguments instead of calling a library routine. If the 466 source contains a large number of arguments that need to be 467 repacked, code size or time for compilation can become excessive. 468 If that is the case, -fno-inline-arg-packing can be used to disable 469 inline argument packing. 470 * Legacy extensions: 471 + For formatted input/output, if the explicit widths after the 472 data-edit descriptors I, F and G have been omitted, default 473 widths are used. 474 + A blank format item at the end of a format specification, i.e. 475 nothing following the final comma, is allowed. Use the option 476 -fdec-blank-format-item; this option is implied with -fdec. 477 + The existing support for AUTOMATIC and STATIC attributes has 478 been extended to allow variables with the AUTOMATIC attribute 479 to be used in EQUIVALENCE statements. Use -fdec-static; this 480 option is implied by -fdec. 481 + Allow character literals in assignments and DATA statements 482 for numeric (INTEGER, REAL, or COMPLEX) or LOGICAL variables. 483 Use the option -fdec-char-conversions; this option is implied 484 with -fdec. 485 + DEC comparisons, i.e. allow Hollerith constants to be used in 486 comparisons with INTEGER, REAL, COMPLEX and CHARACTER 487 expressions. Use the option -fdec. 488 * Character type names in errors and warnings now include len in 489 addition to kind; * is used for assumed length. The kind is omitted 490 if it is the default kind. Examples: CHARACTER(12), CHARACTER(6,4). 491 * CO_BROADCAST now supports derived type variables including objects 492 with allocatable components. In this case, the optional arguments 493 STAT= and ERRMSG= are currently ignored. 494 * The handling of module and submodule names has been reworked to 495 allow the full 63-character length mandated by the standard. 496 Previously symbol names were truncated if the combined length of 497 module, submodule, and function name exceeded 126 characters. This 498 change therefore breaks the ABI, but only for cases where this 126 499 character limit was exceeded. 500 501 Go 502 503 * GCC 10 provides a complete implementation of the Go 1.14.6 user 504 packages. 505 506 libgccjit 507 508 * The libgccjit API gained four new entry points: 509 + [39]gcc_jit_version_major, [40]gcc_jit_version_minor, and 510 [41]gcc_jit_version_patchlevel for programmatically checking 511 the libgccjit version from client code, and 512 + [42]gcc_jit_context_new_bitfield 513 514 New Targets and Target Specific Improvements 515 516 AArch64 & arm 517 518 * The AArch64 and arm ports now support condition flag output 519 constraints in inline assembly, as indicated by the 520 __GCC_ASM_FLAG_OUTPUTS__. On arm this feature is only available for 521 A32 and T32 targets. Please refer to the documentation for more 522 details. 523 524 AArch64 525 526 * There have been several improvements related to the Scalable Vector 527 Extension (SVE): 528 + The SVE ACLE types and intrinsics are now supported. They can 529 be accessed using the header file arm_sve.h. 530 + It is now possible to create fixed-length SVE types using the 531 arm_sve_vector_bits attribute. For example: 532 #if __ARM_FEATURE_SVE_BITS==512 533 typedef svint32_t vec512 __attribute__((arm_sve_vector_bits(512))); 534 typedef svbool_t pred512 __attribute__((arm_sve_vector_bits(512))); 535 #endif 536 + -mlow-precision-div, -mlow-precision-sqrt and 537 -mlow-precision-recip-sqrt now work for SVE. 538 + -msve-vector-bits=128 now generates vector-length-specific 539 code for little-endian targets. It continues to generate 540 vector-length-agnostic code for big-endian targets, just as 541 previous releases did for all targets. 542 + The vectorizer is now able to use extending loads and 543 truncating stores, including gather loads and scatter stores. 544 + The vectorizer now compares the cost of vectorizing with SVE 545 and vectorizing with Advanced SIMD and tries to pick the best 546 one. Previously it would always use SVE if possible. 547 + If a vector loop uses Advanced SIMD rather than SVE, the 548 vectorizer now considers using SVE to vectorize the left-over 549 elements (the "scalar tail" or "epilog"). 550 + Besides these specific points, there have been many general 551 improvements to the way that the vectorizer uses SVE. 552 * The -mbranch-protection=pac-ret option now accepts the optional 553 argument +b-key extension to perform return address signing with 554 the B-key instead of the A-key. 555 * The option -moutline-atomics has been added to aid deployment of 556 the Large System Extensions (LSE) on GNU/Linux systems built with a 557 baseline architecture targeting Armv8-A. When the option is 558 specified code is emitted to detect the presence of LSE 559 instructions at runtime and use them for standard atomic 560 operations. For more information please refer to the documentation. 561 * The Transactional Memory Extension is now supported through ACLE 562 intrinsics. It can be enabled through the +tme option extension 563 (for example, -march=armv8.5-a+tme). 564 * A number of features from Armv8.5-A are now supported through ACLE 565 intrinsics. These include: 566 + The random number instructions that can be enabled through the 567 (already present in GCC 9.1) +rng option extension. 568 + Floating-point intrinsics to round to integer instructions 569 from Armv8.5-A when targeting -march=armv8.5-a or later. 570 + Memory Tagging Extension intrinsics enabled through the 571 +memtag option extension. 572 * Similarly, the following Armv8.6-A features are now supported 573 through ACLE intrinsics: 574 + The bfloat16 extension. This extension is enabled 575 automatically when Armv8.6-A is selected (such as by 576 -march=armv8.6-a). It can also be enabled for Armv8.2-A and 577 later using the +bf16 option extension. 578 + The Matrix Multiply extension. This extension is split into 579 three parts, one for each supported data type: 580 o Support for 8-bit integer matrix multiply instructions. 581 This extension is enabled automatically when Armv8.6-A is 582 selected. It can also be enabled for Armv8.2-A and later 583 using the +i8mm option extension. 584 o Support for 32-bit floating-point matrix multiply 585 instructions. This extension can be enabled using the 586 +f32mm option extension, which also has the effect of 587 enabling SVE. 588 o Support for 64-bit floating-point matrix multiply 589 instructions. This extension can be enabled using the 590 +f64mm option extension, which likewise has the effect of 591 enabling SVE. 592 * SVE2 is now supported through ACLE intrinsics and (to a limited 593 extent) through autovectorization. It can be enabled through the 594 +sve2 option extension (for example, -march=armv8.5-a+sve2). 595 Additional extensions can be enabled through +sve2-sm4, +sve2-aes, 596 +sve2-sha3 and +sve2-bitperm. 597 * Support has been added for the following processors (GCC 598 identifiers in parentheses): 599 + Arm Cortex-A77 (cortex-a77). 600 + Arm Cortex-A76AE (cortex-a76ae). 601 + Arm Cortex-A65 (cortex-a65). 602 + Arm Cortex-A65AE (cortex-a65ae). 603 + Arm Cortex-A34 (cortex-a34). 604 + Marvell ThunderX3 (thunderx3t110). 605 The GCC identifiers can be used as arguments to the -mcpu or -mtune 606 options, for example: -mcpu=cortex-a77 or -mtune=cortex-a65ae or as 607 arguments to the equivalent target attributes and pragmas. 608 609 arm 610 611 * Support for the FDPIC ABI has been added. It uses 64-bit function 612 descriptors to represent pointers to functions, and enables code 613 sharing on MMU-less systems. The corresponding target triple is 614 arm-uclinuxfdpiceabi, and the C library is uclibc-ng. 615 * Support has been added for the Arm EABI on NetBSD through the 616 arm*-*-netbsdelf-*eabi* triplet. 617 * The handling of 64-bit integer operations has been significantly 618 reworked and improved leading to improved performance and reduced 619 stack usage when using 64-bit integral data types. The option 620 -mneon-for-64bits is now deprecated and will be removed in a future 621 release. 622 * Support has been added for the following processors (GCC 623 identifiers in parentheses): 624 + Arm Cortex-A77 (cortex-a77). 625 + Arm Cortex-A76AE (cortex-a76ae). 626 + Arm Cortex-M35P (cortex-m35p). 627 + Arm Cortex-M55 (cortex-m55). 628 The GCC identifiers can be used as arguments to the -mcpu or -mtune 629 options, for example: -mcpu=cortex-a77 or -mtune=cortex-m35p. 630 * Support has been extended for the ACLE [43]data-processing 631 intrinsics to include 32-bit SIMD, saturating arithmetic, 16-bit 632 multiplication and other related intrinsics aimed at DSP algorithm 633 optimization. 634 * Support for -mpure-code in Thumb-1 (v6m) has been added: this 635 M-profile feature is no longer restricted to targets with MOVT. For 636 example, -mcpu=cortex-m0 now supports this option. 637 * Support for the [44]Armv8.1-M Mainline Architecture has been added. 638 + Armv8.1-M Mainline can be enabled by using the 639 -march=armv8.1-m.main command-line option. 640 * Support for the [45]MVE beta ACLE intrinsics has been added. These 641 intrinsics can be enabled by including the arm_mve.h header file 642 and passing the +mve or +mve.fp option extensions (for example: 643 -march=armv8.1-m.main+mve). 644 * Support for the Custom Datapath Extension beta ACLE [46]intrinsics 645 has been added. 646 * Support for Armv8.1-M Mainline Security Extensions architecture has 647 been added. The -mcmse option, when used in combination with an 648 Armv8.1-M Mainline architecture (for example: -march=armv8.1-m.main 649 -mcmse), now leads to the generation of improved code sequences 650 when changing security states. 651 652 AMD Radeon (GCN) 653 654 * Code generation and in particular vectorization support have been 655 much improved. 656 657 ARC 658 659 * The interrupt service routine functions save all used registers, 660 including extension registers and auxiliary registers used by Zero 661 Overhead Loops. 662 * Improve code size by using multiple short instructions instead of a 663 single long mov or ior instruction when its long immediate constant 664 is known. 665 * Fix usage of the accumulator register for ARC600. 666 * Fix issues with uncached attribute. 667 * Remove -mq-class option. 668 * Improve 64-bit integer addition and subtraction operations. 669 670 AVR 671 672 * Support for the XMEGA-like devices 673 674 ATtiny202, ATtiny204, ATtiny402, ATtiny404, ATtiny406, ATtiny804, 675 ATtiny806, ATtiny807, ATtiny1604, ATtiny1606, ATtiny1607, ATmega808, 676 ATmega809, ATmega1608, ATmega1609, ATmega3208, ATmega3209, 677 ATmega4808, ATmega4809 678 has been added. 679 * A new command-line option -nodevicespecs has been added. It allows 680 to provide a custom device-specs file by means of 681 682 avr-gcc -nodevicespecs -specs=my-spec-file <options> 683 and without the need to provide options -B and -mmcu=. See [47]AVR 684 command-line options for details. This feature is also available in 685 GCC 9.3+ and GCC 8.4+. 686 * New command-line options -mdouble=[32,64] and -mlong-double=[32,64] 687 have been added. They allow to choose the size (in bits) of the 688 double and long double types, respectively. Whether or not the 689 mentioned layouts are available, whether the options act as a 690 multilib option, and the default for either option are controlled 691 by the new [48]AVR configure options --with-double= and 692 --with-long-double=. 693 * A new configure option --with-libf7= has been added. It controls to 694 which level avr-libgcc provides 64-bit floating point support by 695 means of [49]Libf7. 696 * A new configure option --with-double-comparison= has been added. 697 It's unlikely you need to set this option by hand. 698 699 IA-32/x86-64 700 701 * Support to expand __builtin_roundeven into the appropriate SSE 4.1 702 instruction has been added. 703 * New ISA extension support for Intel ENQCMD was added to GCC. ENQCMD 704 intrinsics are available via the -menqcmd compiler switch. 705 * GCC now supports the Intel CPU named Cooperlake through 706 -march=cooperlake. The switch enables the AVX512BF16 ISA 707 extensions. 708 * GCC now supports the Intel CPU named Tigerlake through 709 -march=tigerlake. The switch enables the MOVDIRI MOVDIR64B 710 AVX512VP2INTERSECT ISA extensions. 711 712 MIPS 713 714 * The mips*-*-linux* targets now mark object files with appropriate 715 GNU-stack note, facilitating use of non-executable stack hardening 716 on GNU/Linux. The soft-float targets have this feature enabled by 717 default, while for hard-float targets it is required for GCC to be 718 configured with --with-glibc-version=2.31 against glibc 2.31 or 719 later. 720 721 PowerPC / PowerPC64 / RS6000 722 723 * Many vector builtins have been listed as deprecated in the 724 [50]64-Bit ELF V2 ABI Specification for quite a number of years. 725 The vector builtins listed in Tables A.8 through A.10 are now 726 deprecated for GCC 10, and will likely be removed from support in 727 GCC 11. Note that this does not result in any loss of function. 728 These deprecated builtins generally provide somewhat nonsensical 729 argument lists (for example, mixing signed, unsigned, and bool 730 vector arguments arbitrarily), or are duplicate builtins that are 731 inconsistent with the expected naming scheme. We expect that this 732 will be unlikely to affect much if any code, and any required code 733 changes will be trivial. 734 735 PRU 736 737 * A new back end targeting TI PRU I/O processors has been contributed 738 to GCC. 739 740 RISC-V 741 742 * The riscv*-*-* targets now require GNU binutils version 2.30 or 743 later, to support new assembly instructions produced by GCC. 744 745 V850 746 747 * The ABI for V850 nested functions has been changed. Previously the 748 V850 port used %r20 for the static chain pointer, now the port uses 749 %r19. This corrects a long standing latent bug in the v850 port 750 where a call to a nested function would unexpectedly change the 751 value in %r20. 752 753 Operating Systems 754 755 Improvements for plugin authors 756 757 * GCC diagnostics can now have a chain of events associated with 758 them, describing a path through the code that triggers the problem. 759 These can be printed by the diagnostics subsystem in various ways, 760 controlled by the [51]-fdiagnostics-path-format option, or captured 761 in JSON form via [52]-fdiagnostics-format=json. 762 * GCC diagnostics can now be associated with [53]CWE weakness 763 identifiers, which will appear on the standard error stream, and in 764 the JSON output from [54]-fdiagnostics-format=json. 765 766 Other significant improvements 767 768 * To allow inline expansion of both memcpy and memmove, the existing 769 movmem instruction patterns used for non-overlapping memory copies 770 have been renamed to cpymem. The movmem name is now used for 771 overlapping memory moves, consistent with the library functions 772 memcpy and memmove. 773 * For many releases, when GCC emits a warning it prints the option 774 controlling that warning. As of GCC 10, that option text is now a 775 clickable hyperlink for the documentation of that option (assuming 776 a [55]sufficiently capable terminal). This behavior can be 777 controlled via a new [56]-fdiagnostics-urls option (along with 778 various environment variables and heuristics documented with that 779 option). 780 781 GCC 10.1 782 783 This is the [57]list of problem reports (PRs) from GCC's bug tracking 784 system that are known to be fixed in the 10.1 release. This list might 785 not be complete (that is, it is possible that some PRs that have been 786 fixed are not listed here). 787 788 GCC 10.2 789 790 This is the [58]list of problem reports (PRs) from GCC's bug tracking 791 system that are known to be fixed in the 10.2 release. This list might 792 not be complete (that is, it is possible that some PRs that have been 793 fixed are not listed here). 794 795 GCC 10.3 796 797 This is the [59]list of problem reports (PRs) from GCC's bug tracking 798 system that are known to be fixed in the 10.3 release. This list might 799 not be complete (that is, it is possible that some PRs that have been 800 fixed are not listed here). 801 802 Target Specific Changes 803 804 AArch64 805 806 * A bug with the Random Number intrinsics in the arm_acle.h header 807 that resulted in an incorrect status result being returned has been 808 fixed. 809 * GCC now supports the Fujitsu A64FX. The associated -mcpu and -mtune 810 options are -mcpu=a64fx and -mtune=a64fx respectively. In 811 particular, -mcpu=a64fx generates code for Armv8.2-A with SVE and 812 tunes the code for the A64FX. This includes tuning the SVE code, 813 although by default the code is still length-agnostic and so works 814 for all SVE implementations. Adding -msve-vector-bits=512 makes the 815 code specific to 512-bit SVE. 816 817 x86-64 818 819 * GCC 10.3 supports AMD CPUs based on the znver3 core via 820 -march=znver3. 821 822 GCC 10.4 823 824 This is the [60]list of problem reports (PRs) from GCC's bug tracking 825 system that are known to be fixed in the 10.4 release. This list might 826 not be complete (that is, it is possible that some PRs that have been 827 fixed are not listed here). 828 829 Target Specific Changes 830 831 x86-64 832 833 * The x86-64 ABI of passing and returning structures with a 64-bit 834 integer vector changed in GCC 10.1 when MMX is disabled. Disabling 835 MMX no longer changes how they are passed nor returned. This ABI 836 change is now diagnosed with -Wpsabi. 837 838 GCC 10.5 839 840 This is the [61]list of problem reports (PRs) from GCC's bug tracking 841 system that are known to be fixed in the 10.5 release. This list might 842 not be complete (that is, it is possible that some PRs that have been 843 fixed are not listed here). 844 845 846 For questions related to the use of GCC, please consult these web 847 pages and the [62]GCC manuals. If that fails, the 848 [63]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 849 web pages and the development of GCC are welcome on our developer 850 list at [64]gcc (a] gcc.gnu.org. All of [65]our lists have public 851 archives. 852 853 Copyright (C) [66]Free Software Foundation, Inc. Verbatim copying and 854 distribution of this entire article is permitted in any medium, 855 provided this notice is preserved. 856 857 These pages are [67]maintained by the GCC team. Last modified 858 2023-07-07. 859 860 References 861 862 1. http://gcc.gnu.org/gcc-10/porting_to.html 863 2. http://gcc.gnu.org/onlinedocs/index.html#current 864 3. http://gcc.gnu.org/gcc-10/changes.html#empty_base 865 4. https://www.mpfr.org/ 866 5. http://gcc.gnu.org/gcc-10/changes.html#iterator_base 867 6. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/cpp/_005f_005fhas_005fbuiltin.html#g_t_005f_005fhas_005fbuiltin 868 7. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Optimize-Options.html#index-fno-allocation-dce 869 8. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Optimize-Options.html#index-fprofile-partial-training 870 9. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Instrumentation-Options.html#index-fprofile-reproducible 871 10. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Instrumentation-Options.html#index-fprofile-generate 872 11. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Instrumentation-Options.html#index-fprofile-prefix-path 873 12. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Static-Analyzer-Options.html 874 13. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Optimize-Options.html#index-finline-functions 875 14. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/lto-dump.html 876 15. https://facebook.github.io/zstd/ 877 16. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Optimize-Options.html#index-fprofile-values 878 17. https://www.openacc.org/ 879 18. https://gcc.gnu.org/wiki/OpenACC/Implementation%20Status#status-10 880 19. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/libgomp/#toc-Enabling-OpenACC-1 881 20. https://www.openmp.org/specifications/ 882 21. https://gcc.gnu.org/wiki/Offloading 883 22. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Wstring-compare 884 23. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Wzero-length-bounds 885 24. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Warray-bounds 886 25. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Wformat-overflow 887 26. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Wrestrict 888 27. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Wreturn-local-addr 889 28. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Wstringop-overflow 890 29. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Warning-Options.html#index-Warith-conversion 891 30. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Wmismatched-tags 892 31. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Wredundant-tags 893 32. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94383 894 33. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94711 895 34. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94707 896 35. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94704 897 36. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94706 898 37. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92285 899 38. https://www.openmp.org/specifications/ 900 39. https://gcc.gnu.org/onlinedocs/jit/topics/compatibility.html#c.gcc_jit_version_major 901 40. https://gcc.gnu.org/onlinedocs/jit/topics/compatibility.html#c.gcc_jit_version_minor 902 41. https://gcc.gnu.org/onlinedocs/jit/topics/compatibility.html#c.gcc_jit_version_patchlevel 903 42. https://gcc.gnu.org/onlinedocs/jit/topics/types.html#c.gcc_jit_context_new_bitfield 904 43. https://developer.arm.com/documentation/101028/0009/Data-processing-intrinsics 905 44. https://developer.arm.com/Architectures/M-Profile%20Architecture 906 45. https://developer.arm.com/architectures/instruction-sets/intrinsics/ 907 46. https://developer.arm.com/documentation/101028/0010/Custom-Datapath-Extension 908 47. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/AVR-Options.html#index-nodevicespecs 909 48. https://gcc.gnu.org/install/configure.html#avr 910 49. https://gcc.gnu.org/wiki/avr-gcc#Libf7 911 50. https://openpowerfoundation.org/?resource_lib=64-bit-elf-v2-abi-specification-power-architecture 912 51. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fdiagnostics-path-format 913 52. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fdiagnostics-format 914 53. https://cwe.mitre.org/ 915 54. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fdiagnostics-format 916 55. https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda 917 56. https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fdiagnostics-urls 918 57. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=10.0 919 58. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=10.2 920 59. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=10.3 921 60. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=10.4 922 61. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=10.5 923 62. https://gcc.gnu.org/onlinedocs/ 924 63. mailto:gcc-help (a] gcc.gnu.org 925 64. mailto:gcc (a] gcc.gnu.org 926 65. https://gcc.gnu.org/lists.html 927 66. https://www.fsf.org/ 928 67. https://gcc.gnu.org/about.html 929 ====================================================================== 930 http://gcc.gnu.org/gcc-9/index.html 931 932 GCC 9 Release Series 933 934 (This release series is no longer supported.) 935 936 May 27, 2022 937 938 The [1]GNU project and the GCC developers are pleased to announce the 939 release of GCC 9.5. 940 941 This release is a bug-fix release, containing fixes for regressions in 942 GCC 9.4 relative to previous releases of GCC. 943 944 Release History 945 946 GCC 9.5 947 May 27, 2022 ([2]changes, [3]documentation) 948 949 GCC 9.4 950 June 1, 2021 ([4]changes, [5]documentation) 951 952 GCC 9.3 953 Mar 12, 2020 ([6]changes, [7]documentation) 954 955 GCC 9.2 956 Aug 12, 2019 ([8]changes, [9]documentation) 957 958 GCC 9.1 959 May 3, 2019 ([10]changes, [11]documentation) 960 961 References and Acknowledgements 962 963 GCC used to stand for the GNU C Compiler, but since the compiler 964 supports several other languages aside from C, it now stands for the 965 GNU Compiler Collection. 966 967 A list of [12]successful builds is updated as new information becomes 968 available. 969 970 The GCC developers would like to thank the numerous people that have 971 contributed new features, improvements, bug fixes, and other changes as 972 well as test results to GCC. This [13]amazing group of volunteers is 973 what makes GCC successful. 974 975 For additional information about GCC please refer to the [14]GCC 976 project web site or contact the [15]GCC development mailing list. 977 978 To obtain GCC please use [16]our mirror sites or [17]our version 979 control system. 980 981 982 For questions related to the use of GCC, please consult these web 983 pages and the [18]GCC manuals. If that fails, the 984 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 985 web pages and the development of GCC are welcome on our developer 986 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 987 archives. 988 989 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 990 distribution of this entire article is permitted in any medium, 991 provided this notice is preserved. 992 993 These pages are [23]maintained by the GCC team. Last modified 994 2022-10-26. 995 996 References 997 998 1. http://www.gnu.org/ 999 2. http://gcc.gnu.org/gcc-9/changes.html 1000 3. http://gcc.gnu.org/onlinedocs/9.5.0/ 1001 4. http://gcc.gnu.org/gcc-9/changes.html 1002 5. http://gcc.gnu.org/onlinedocs/9.4.0/ 1003 6. http://gcc.gnu.org/gcc-9/changes.html 1004 7. http://gcc.gnu.org/onlinedocs/9.3.0/ 1005 8. http://gcc.gnu.org/gcc-9/changes.html 1006 9. http://gcc.gnu.org/onlinedocs/9.2.0/ 1007 10. http://gcc.gnu.org/gcc-9/changes.html 1008 11. http://gcc.gnu.org/onlinedocs/9.1.0/ 1009 12. http://gcc.gnu.org/gcc-9/buildstat.html 1010 13. http://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Contributors.html 1011 14. http://gcc.gnu.org/index.html 1012 15. mailto:gcc (a] gcc.gnu.org 1013 16. http://gcc.gnu.org/mirrors.html 1014 17. http://gcc.gnu.org/git.html 1015 18. https://gcc.gnu.org/onlinedocs/ 1016 19. mailto:gcc-help (a] gcc.gnu.org 1017 20. mailto:gcc (a] gcc.gnu.org 1018 21. https://gcc.gnu.org/lists.html 1019 22. https://www.fsf.org/ 1020 23. https://gcc.gnu.org/about.html 1021 ====================================================================== 1022 http://gcc.gnu.org/gcc-9/changes.html 1023 1024 GCC 9 Release Series 1025 Changes, New Features, and Fixes 1026 1027 This page is a "brief" summary of some of the huge number of 1028 improvements in GCC 9. You may also want to check out our [1]Porting to 1029 GCC 9 page and the [2]full GCC documentation. 1030 1031 Caveats 1032 1033 * On Arm targets (arm*-*-*), [3]a bug in the implementation of the 1034 procedure call standard (AAPCS) in the GCC 6, 7 and 8 releases has 1035 been fixed: a structure containing a bit-field based on a 64-bit 1036 integral type and where no other element in a structure required 1037 64-bit alignment could be passed incorrectly to functions. This is 1038 an ABI change. If the option -Wpsabi is enabled (on by default) the 1039 compiler will emit a diagnostic note for code that might be 1040 affected. 1041 * Support for a number of older systems and recently unmaintained or 1042 untested target ports of GCC has been declared obsolete in GCC 9. 1043 Unless there is activity to revive them, the next release of GCC 1044 will have their sources permanently removed. 1045 The following ports for individual systems on particular 1046 architectures have been obsoleted: 1047 + Solaris 10 (*-*-solaris2.10). Details can be found in the 1048 [4]announcement. 1049 + Cell Broadband Engine SPU (spu*-*-*). Details can be found in 1050 the [5]announcement. 1051 * A change to the C++ std::rotate algorithm in GCC 9.1.0 can cause 1052 ABI incompatibilities with object files compiled with other 1053 versions of GCC. If the std::rotate algorithm is called with an 1054 empty range then it might cause a divide-by-zero error (as a SIGFPE 1055 signal) and crash. The change has been reverted for GCC 9.2.0 and 1056 future releases. For more details see [6]Bug 90920. The problem can 1057 be avoided by recompiling any objects that might call std::rotate 1058 with an empty range, so that the GCC 9.1.0 definition of 1059 std::rotate is not used. 1060 * The automatic template instantiation at link time ([7]-frepo) has 1061 been deprecated and will be removed in a future release. 1062 * The --with-default-libstdcxx-abi=gcc4-compatible configure option 1063 is broken in the 9.1 and 9.2 releases, producing a shared library 1064 with missing symbols (see [8]Bug 90361). As a workaround, configure 1065 without that option and build GCC as normal, then edit the 1066 installed <bits/c++config.h> headers to define the 1067 _GLIBCXX_USE_CXX11_ABI macro to 0. 1068 1069 General Improvements 1070 1071 The following GCC command line options have been introduced or 1072 improved. 1073 * All command line options that take a byte-size argument accept 1074 64-bit integers as well as standard SI and IEC suffixes such as kb 1075 and KiB, MB and MiB, or GB and GiB denoting the corresponding 1076 multiples of bytes. See [9]Invoking GCC for more. 1077 * A new option [10]-flive-patching=[inline-only-static|inline-clone] 1078 generates code suitable for live patching. At the same time it 1079 provides multiple-level control over IPA optimizations. See the 1080 user guide for more details. 1081 * A new option, --completion, has been added to provide more fine 1082 option completion in a shell. It is intended to be used by 1083 Bash-completion. 1084 * GCC's diagnostics now print source code with a left margin showing 1085 line numbers, configurable with 1086 [11]-fno-diagnostics-show-line-numbers. 1087 GCC's diagnostics can also now label regions of the source code to 1088 show pertinent information, such as the types within an expression. 1089 $ g++ t.cc 1090 t.cc: In function 'int test(const shape&, const shape&)': 1091 t.cc:15:4: error: no match for 'operator+' (operand types are 'boxed_value<doubl 1092 e>' and 'boxed_value<double>') 1093 14 | return (width(s1) * height(s1) 1094 | ~~~~~~~~~~~~~~~~~~~~~~ 1095 | | 1096 | boxed_value<[...]> 1097 15 | + width(s2) * height(s2)); 1098 | ^ ~~~~~~~~~~~~~~~~~~~~~~ 1099 | | 1100 | boxed_value<[...]> 1101 1102 These labels can be disabled via [12]-fno-diagnostics-show-labels. 1103 * A new option [13]-fdiagnostics-format=json has been introduced for 1104 emitting diagnostics in a machine-readable format. 1105 * The alignment-related options [14]-falign-functions, 1106 [15]-falign-labels, [16]-falign-loops, and [17]-falign-jumps 1107 received support for a secondary alignment (e.g. 1108 -falign-loops=n:m:n2:m2). 1109 * New pair of profiling options ([18]-fprofile-filter-files and 1110 [19]-fprofile-exclude-files) has been added. The options help to 1111 filter which source files are instrumented. 1112 * AddressSanitizer generates more compact redzones for automatic 1113 variables. That helps to reduce memory footprint of a sanitized 1114 binary. 1115 * Numerous improvements have been made to the output of 1116 [20]-fopt-info. 1117 Messages are now prefixed with optimized, missed, or note, rather 1118 than the old behavior of all being prefixed with note. 1119 The output from -fopt-info can now contain information on inlining 1120 decisions: 1121 $ g++ -c inline.cc -O2 -fopt-info-inline-all 1122 inline.cc:24:11: note: Considering inline candidate void foreach(T, T, void (*)( 1123 E)) [with T = char**; E = char*]/2. 1124 inline.cc:24:11: optimized: Inlining void foreach(T, T, void (*)(E)) [with T = 1125 char**; E = char*]/2 into int main(int, char**)/1. 1126 inline.cc:19:12: missed: not inlinable: void inline_me(char*)/0 -> int std::pu 1127 ts(const char*)/3, function body not available 1128 inline.cc:13:8: optimized: Inlined void inline_me(char*)/4 into int main(int, c 1129 har**)/1 which now has time 127.363637 and size 11, net change of +0. 1130 Unit growth for small function inlining: 16->16 (0%) 1131 1132 Inlined 2 calls, eliminated 1 functions 1133 1134 1135 The output from the vectorizer has been rationalized so that failed 1136 attempts to vectorize a loop are displayed in the form 1137 [LOOP-LOCATION]: couldn't vectorize this loop 1138 [PROBLEM-LOCATION]: because of [REASON] 1139 1140 rather than an exhaustive log of all decisions made by the 1141 vectorizer. For example: 1142 $ gcc -c v.c -O3 -fopt-info-all-vec 1143 v.c:7:3: missed: couldn't vectorize loop 1144 v.c:10:7: missed: statement clobbers memory: __asm__ __volatile__("" : : : "me 1145 mory"); 1146 v.c:3:6: note: vectorized 0 loops in function. 1147 v.c:10:7: missed: statement clobbers memory: __asm__ __volatile__("" : : : "me 1148 mory"); 1149 1150 The old behavior can be obtained via a new -internals suboption of 1151 -fopt-info. 1152 * A new option, [21]-fsave-optimization-record has been added, which 1153 writes a SRCFILE.opt-record.json.gz file describing the 1154 optimization decisions made by GCC. This is similar to the output 1155 of -fopt-info, but with additional metadata such as the inlining 1156 chain, and profile information (if available). 1157 * Inter-procedural propagation of stack alignment can now be 1158 controlled by [22]-fipa-stack-alignment. 1159 * Propagation of addressability, readonly and writeonly flags on 1160 static variables can now be controlled by 1161 [23]-fipa-reference-addressable. 1162 1163 The following built-in functions have been introduced. 1164 * [24]__builtin_expect_with_probability to provide branch prediction 1165 probability hints to the optimizer. 1166 * [25]__builtin_has_attribute determines whether a function, type, or 1167 variable has been declared with some attribute. 1168 * [26]__builtin_speculation_safe_value can be used to help mitigate 1169 against unsafe speculative execution. 1170 1171 The following attributes have been introduced. 1172 * The [27]copy function attribute has been added. The attribute can 1173 also be applied to type definitions and to variable declarations. 1174 1175 A large number of improvements to code generation have been made, 1176 including but not limited to the following. 1177 * Switch expansion has been improved by using a different strategy 1178 (jump table, bit test, decision tree) for a subset of switch cases. 1179 * A linear function expression defined as a switch statement can be 1180 transformed by [28]-ftree-switch-conversion. For example: 1181 1182 int 1183 foo (int how) 1184 { 1185 switch (how) { 1186 case 2: how = 205; break; 1187 case 3: how = 305; break; 1188 case 4: how = 405; break; 1189 case 5: how = 505; break; 1190 case 6: how = 605; break; 1191 } 1192 return how; 1193 } 1194 1195 can be transformed into 100 * how + 5 (for values defined in the 1196 switch statement). 1197 * Inter-procedural optimization improvements: 1198 + Inliner defaults was tuned to better suits modern C++ 1199 codebases especially when built with link time optimizations. 1200 New parameters max-inline-insns-small, max-inline-insns-size, 1201 uninlined-function-insns, uninlined-function-time, 1202 uninlined-thunk-insns, and uninlined-thunk-time were added. 1203 + Hot/cold partitioning is now more precise and aggressive. 1204 + Improved scalability for very large translation units 1205 (especially when link-time optimizing large programs). 1206 * Profile driven optimization improvements: 1207 + [29]-fprofile-use now enables [30]-fversion-loops-for-strides, 1208 [31]-floop-interchange, [32]-floop-unroll-and-jam, 1209 [33]-ftree-loop-distribution. 1210 + Streaming of counter histograms was removed. This reduces the 1211 size of profile files. Histogram is computed on the fly with 1212 link-time optimization. Parameter hot-bb-count-ws-permille was 1213 reduced from 999 to 990 to account for more precise 1214 histograms. 1215 * Link-time optimization improvements: 1216 + Types are now simplified prior streaming resulting in 1217 significant reductions of the LTO object files, link-time 1218 memory use, and improvements of link-time parallelism. 1219 + Default number of partitions (--param lto-partitions) was 1220 increased from 32 to 128 enabling effective use of CPUs with 1221 more than 32 hyperthreads. --param 1222 lto-max-streaming-parallelism can now be used to control 1223 number of streaming processes. 1224 + Warnings on C++ One Decl Rule violations (-Wodr) are now more 1225 informative and produce fewer redundant results. 1226 Overall compile time of Firefox 66 and LibreOffice 6.2.3 on an 1227 8-core machine was reduced by about 5% compared to GCC 8.3, and the 1228 size of LTO object files by 7%. LTO link-time improves by 11% on an 1229 8-core machine and scales significantly better for more parallel 1230 build environments. The serial stage of the link-time optimization 1231 is 28% faster consuming 20% less memory. The parallel stage now 1232 scales to up to 128 partitions rather than 32 and reduces memory 1233 use for every worker by 30%. 1234 1235 The following improvements to the gcov command-line utility have been 1236 made. 1237 * The gcov tool received a new option [34]--use-hotness-colors (-q) 1238 that can provide perf-like coloring of hot functions. 1239 * The gcov tool has changed its intermediate format to a new JSON 1240 format. 1241 1242 New Languages and Language specific improvements 1243 1244 [35]OpenACC support in C, C++, and Fortran continues to be maintained 1245 and improved. Most of the OpenACC 2.5 specification is implemented. See 1246 the [36]implementation status section on the OpenACC wiki page for 1247 further information. 1248 1249 C family 1250 1251 * Version 5.0 of the [37]OpenMP specification is now partially 1252 supported in the C and C++ compilers. For details which features of 1253 OpenMP 5.0 are and which are not supported in the GCC 9 release see 1254 [38]this mail. 1255 * New extensions: 1256 + [39]__builtin_convertvector built-in for vector conversions 1257 has been added. 1258 * New warnings: 1259 + [40]-Waddress-of-packed-member, enabled by default, warns 1260 about an unaligned pointer value from the address of a packed 1261 member of a struct or union. 1262 * Enhancements to existing warnings: 1263 + [41]-Warray-bounds detects more instances of out-of-bounds 1264 indices. 1265 + [42]-Wattribute-alias also detects attribute mismatches 1266 between alias declarations and their targets, in addition to 1267 mismatches between their types. 1268 + [43]-Wformat-overflow and [44]-Wformat-truncation have been 1269 extended to all formatted input/output functions (where 1270 applicable) and enhanced to detect a subset of instances of 1271 reading past the end of unterminated constant character arrays 1272 in %s directives. 1273 + [45]-Wmissing-attributes detects instances of missing function 1274 attributes on declarations of aliases and weak references. 1275 + [46]-Wstringop-truncation also detects a subset of instances 1276 of reading past the end of unterminated constant character 1277 arrays, 1278 * If a macro is used with the wrong argument count, the C and C++ 1279 front ends now show the definition of that macro via a note. 1280 * The spelling corrector now considers transposed letters, and the 1281 threshold for similarity has been tightened, to avoid nonsensical 1282 suggestions. 1283 1284 C 1285 1286 * There is now experimental support for -std=c2x, to select support 1287 for the upcoming C2X revision of the ISO C standard. This standard 1288 is in the early stages of development and the only feature 1289 supported in GCC 9 is _Static_assert with a single argument 1290 (support for _Static_assert with two arguments was added in C11 and 1291 GCC 4.6). There are also new options -std=gnu2x, for C2X with GNU 1292 extensions, and -Wc11-c2x-compat, to warn for uses of features 1293 added in C2X (such warnings are also enabled by use of -Wpedantic 1294 if not using -std=c2x or -std=gnu2x). 1295 * New warnings: 1296 + [47]-Wabsolute-value warns for calls to standard functions 1297 that compute the absolute value of an argument when a more 1298 appropriate standard function is available. For example, 1299 calling abs(3.14) triggers the warning because the appropriate 1300 function to call to compute the absolute value of a double 1301 argument is fabs. The option also triggers warnings when the 1302 argument in a call to such a function has an unsigned type. 1303 This warning can be suppressed with an explicit type cast and 1304 it is also enabled by -Wextra. 1305 1306 C++ 1307 1308 * New warnings: 1309 + [48]-Wdeprecated-copy, implied by -Wextra, warns about the 1310 C++11 deprecation of implicitly declared copy constructor and 1311 assignment operator if one of them is user-provided. 1312 -Wdeprecated-copy-dtor also warns if the destructor is 1313 user-provided, as specified in C++11. 1314 + [49]-Winit-list-lifetime, on by default, warns about uses of 1315 std::initializer_list that are likely to result in a dangling 1316 pointer, such as returning or assigning from a temporary list. 1317 + [50]-Wredundant-move, implied by -Wextra, warns about 1318 redundant calls to std::move. 1319 + [51]-Wpessimizing-move, implied by -Wall, warns when a call to 1320 std::move prevents copy elision. 1321 + [52]-Wclass-conversion, on by default, warns when a conversion 1322 function will never be called due to the type it converts to. 1323 * The C++ front end has experimental support for some of the upcoming 1324 C++2a draft features with the -std=c++2a or -std=gnu++2a flags, 1325 including range-based for statements with initializer, default 1326 constructible and assignable stateless lambdas, lambdas in 1327 unevaluated contexts, language support for empty data members, 1328 allowing pack expansion in lambda init-capture, likely and unlikely 1329 attributes, class types in non-type template parameters, allowing 1330 virtual function calls in constant expressions, explicit(bool), 1331 std::is_constant_evaluated, nested inline namespaces, etc. For a 1332 full list of new features, see [53]the C++ status page. 1333 * The C++ front end now preserves source locations for literals, 1334 id-expression, and mem-initializer for longer. For example it is 1335 now able to pin-point the pertinent locations for bad 1336 initializations such as these 1337 $ g++ -c bad-inits.cc 1338 bad-inits.cc:10:14: error: cannot convert 'json' to 'int' in initialization 1339 10 | { 3, json::object }, 1340 | ~~~~~~^~~~~~ 1341 | | 1342 | json 1343 bad-inits.cc:14:31: error: initializer-string for array of chars is too long [-f 1344 permissive] 1345 14 | char buffers[3][5] = { "red", "green", "blue" }; 1346 | ^~~~~~~ 1347 bad-inits.cc: In constructor 'X::X()': 1348 bad-inits.cc:17:13: error: invalid conversion from 'int' to 'void*' [-fpermissiv 1349 e] 1350 17 | X() : one(42), two(42), three(42) 1351 | ^~ 1352 | | 1353 | int 1354 1355 rather than emitting the error at the final closing parenthesis or 1356 brace. 1357 * Error-reporting of overload resolution has been special-cased to 1358 make the case of a single failed candidate easier to read. For 1359 example: 1360 $ g++ param-type-mismatch.cc 1361 param-type-mismatch.cc: In function 'int test(int, const char*, float)': 1362 param-type-mismatch.cc:8:32: error: cannot convert 'const char*' to 'const char* 1363 *' 1364 8 | return foo::member_1 (first, second, third); 1365 | ^~~~~~ 1366 | | 1367 | const char* 1368 param-type-mismatch.cc:3:46: note: initializing argument 2 of 'static int foo: 1369 :member_1(int, const char**, float)' 1370 3 | static int member_1 (int one, const char **two, float three); 1371 | ~~~~~~~~~~~~~^~~ 1372 1373 highlights both the problematic argument, and the parameter that it 1374 can't be converted to. 1375 * Diagnostics involving binary operators now use color to distinguish 1376 the two operands, and label them separately (as per the example of 1377 source labelling above). 1378 * Diagnostics involving function calls now highlight the pertinent 1379 parameter of the declaration in more places. 1380 $ g++ bad-conversion.cc 1381 bad-conversion.cc: In function 'void caller()': 1382 bad-conversion.cc:9:14: error: cannot convert 'bool' to 'void*' 1383 9 | callee (0, false, 2); 1384 | ^~~~~ 1385 | | 1386 | bool 1387 bad-conversion.cc:3:19: note: initializing argument 2 of 'void callee(int, voi 1388 d*, int)' 1389 3 | void callee (int, void *, int) 1390 | ^~~~~~ 1391 1392 * The C++ front end's implementation of [54]-Wformat now shows 1393 precise locations within string literals, and underlines the 1394 pertinent arguments at bogus call sites (the C front end has been 1395 doing this since GCC 7). For example: 1396 $ g++ -c bad-printf.cc -Wall 1397 bad-printf.cc: In function 'void print_field(const char*, float, long int, long 1398 int)': 1399 bad-printf.cc:6:17: warning: field width specifier '*' expects argument of type 1400 'int', but argument 3 has type 'long int' [-Wformat=] 1401 6 | printf ("%s: %*ld ", fieldname, column - width, value); 1402 | ~^~~ ~~~~~~~~~~~~~~ 1403 | | | 1404 | int long int 1405 bad-printf.cc:6:19: warning: format '%ld' expects argument of type 'long int', b 1406 ut argument 4 has type 'double' [-Wformat=] 1407 6 | printf ("%s: %*ld ", fieldname, column - width, value); 1408 | ~~~^ ~~~~~ 1409 | | | 1410 | long int double 1411 | %*f 1412 1413 * The C++ front end has gained new fix-it hints for forgetting the 1414 return *this; needed by various C++ operators: 1415 $ g++ -c operator.cc 1416 operator.cc: In member function 'boxed_ptr& boxed_ptr::operator=(const boxed_ptr 1417 &)': 1418 operator.cc:7:3: warning: no return statement in function returning non-void [-W 1419 return-type] 1420 6 | m_ptr = other.m_ptr; 1421 +++ |+ return *this; 1422 7 | } 1423 | ^ 1424 1425 for when the compiler needs a typename: 1426 $ g++ -c template.cc 1427 template.cc:3:3: error: need 'typename' before 'Traits::type' because 'Traits' i 1428 s a dependent scope 1429 3 | Traits::type type; 1430 | ^~~~~~ 1431 | typename 1432 1433 when trying to use an accessor member as if it were a data member: 1434 $ g++ -c fncall.cc 1435 fncall.cc: In function 'void hangman(const mystring&)': 1436 fncall.cc:12:11: error: invalid use of member function 'int mystring::get_length 1437 () const' (did you forget the '()' ?) 1438 12 | if (str.get_length > 0) 1439 | ~~~~^~~~~~~~~~ 1440 | () 1441 1442 for C++11's scoped enums: 1443 $ g++ -c enums.cc 1444 enums.cc: In function 'void json::test(const json::value&)': 1445 enums.cc:12:26: error: 'STRING' was not declared in this scope; did you mean 'js 1446 on::kind::STRING'? 1447 12 | if (v.get_kind () == STRING) 1448 | ^~~~~~ 1449 | json::kind::STRING 1450 enums.cc:3:44: note: 'json::kind::STRING' declared here 1451 3 | enum class kind { OBJECT, ARRAY, NUMBER, STRING, TRUE, FALSE, NULL_ }; 1452 | ^~~~~~ 1453 1454 and a tweak to integrate the suggestions about misspelled members 1455 with that for accessors: 1456 $ g++ -c accessor-fixit.cc 1457 accessor-fixit.cc: In function 'int test(t*)': 1458 accessor-fixit.cc:17:15: error: 'class t' has no member named 'ratio'; did you m 1459 ean 'int t::m_ratio'? (accessible via 'int t::get_ratio() const') 1460 17 | return ptr->ratio; 1461 | ^~~~~ 1462 | get_ratio() 1463 1464 In addition, various diagnostics in the C++ front-end have been 1465 streamlined by consolidating the suggestion into the initial error, 1466 rather than emitting a follow-up note: 1467 $ g++ typo.cc 1468 typo.cc:5:13: error: 'BUFSIZE' was not declared in this scope; did you mean 'BUF 1469 _SIZE'? 1470 5 | uint8_t buf[BUFSIZE]; 1471 | ^~~~~~~ 1472 | BUF_SIZE 1473 1474 Runtime Library (libstdc++) 1475 1476 * Improved support for C++17, including: 1477 + The C++17 implementation is no longer experimental. 1478 + Parallel algorithms and <execution> (requires [55]Thread 1479 Building Blocks 2018 or newer). 1480 + <memory_resource>. 1481 + Using the types and functions in <filesystem> does not require 1482 linking with -lstdc++fs now. 1483 * Improved experimental support for C++2a, including: 1484 + Type traits std::remove_cvref, std::unwrap_reference, 1485 std::unwrap_decay_ref, std::is_nothrow_convertible, and 1486 std::type_identity. 1487 + Headers <bit> and <version>. 1488 + Uniform container erasure (std::erase_if). 1489 + contains member of maps and sets. 1490 + String prefix and suffix checking (starts_with, ends_with). 1491 + Functions std::midpoint and std::lerp for interpolation. 1492 + std::bind_front. 1493 + std::visit<R>. 1494 + std::assume_aligned. 1495 + Uses-allocator construction utilities. 1496 + std::pmr::polymorphic_allocator<std::byte>. 1497 + Library support for char8_t type. 1498 + Destroying delete. 1499 + std::is_constant_evaluated() function. 1500 * Support for opening file streams with wide character paths on 1501 Windows 1502 * Incomplete support for the C++17 Filesystem library and the 1503 Filesystem TS on Windows. 1504 * Incomplete, experimental support for the Networking TS. 1505 1506 D 1507 1508 * Support for the D programming language has been added to GCC, 1509 implementing version 2.076 of the language and run-time library. 1510 1511 Fortran 1512 1513 * Asynchronous I/O is now fully supported. The program needs to be 1514 linked against the pthreads library to use it, otherwise the I/O is 1515 done synchronously. For systems which do not support POSIX 1516 condition variables, such as AIX, all I/O is still done 1517 synchronously. 1518 * The BACK argument for MINLOC and MAXLOC has been implemented. 1519 * The FINDLOC intrinsic function has been implemented. 1520 * The IS_CONTIGUOUS intrinsic function has been implemented. 1521 * Direct access to the real and imaginary parts of a complex variable 1522 via c%re and c%im has been implemented. 1523 * Type parameter inquiry via str%len and a%kind has been implemented. 1524 * C descriptors and the ISO_Fortran_binding.h source file have been 1525 implemented. 1526 * The MAX and MIN intrinsics are no longer guaranteed to return any 1527 particular value in case one of the arguments is a NaN. Note that 1528 this conforms to the Fortran standard and to what other Fortran 1529 compilers do. If there is a need to handle that case in some 1530 specific way, one needs to explicitly check for NaN's before 1531 calling MAX or MIN, e.g. by using the IEEE_IS_NAN function from the 1532 intrinsic module IEEE_ARITHMETIC. 1533 * A new command-line option [56]-fdec-include, set also by the 1534 [57]-fdec option, has been added to increase compatibility with 1535 legacy code. With this option, an INCLUDE directive is also parsed 1536 as a statement, which allows the directive to be spread across 1537 multiple source lines with line continuations. 1538 * A new [58]BUILTIN directive, has been added. The purpose of the 1539 directive is to provide an API between the GCC compiler and the GNU 1540 C Library which would define vector implementations of math 1541 routines. 1542 1543 Go 1544 1545 * GCC 9 provides a complete implementation of the Go 1.12.2 user 1546 packages. 1547 1548 libgccjit 1549 1550 * The libgccjit API gained a new entry point: 1551 [59]gcc_jit_context_add_driver_option. 1552 1553 New Targets and Target Specific Improvements 1554 1555 AArch64 & Arm 1556 1557 * Support has been added for the following processors (GCC 1558 identifiers in parentheses): 1559 + Arm Cortex-A76 (cortex-a76). 1560 + Arm Cortex-A55/Cortex-A76 DynamIQ big.LITTLE 1561 (cortex-a76.cortex-a55). 1562 + Arm Neoverse N1 (neoverse-n1). 1563 The GCC identifiers can be used as arguments to the -mcpu or -mtune 1564 options, for example: -mcpu=cortex-a76 or 1565 -mtune=cortex-a76.cortex-a55 or as arguments to the equivalent 1566 target attributes and pragmas. 1567 * The Armv8.3-A complex number instructions are now supported via 1568 intrinsics when the option -march=armv8.3-a or equivalent is 1569 specified. For the half-precision floating-point variants of these 1570 instructions use the architecture extension flag +fp16, e.g. 1571 -march=armv8.3-a+fp16. 1572 The intrinsics are defined by the ACLE specification. 1573 * The Armv8.5-A architecture is now supported through the 1574 -march=armv8.5-a option. 1575 * The Armv8.5-A architecture also adds some security features that 1576 are optional to all older architecture versions. These are now 1577 supported and only affect the assembler. 1578 + Speculation Barrier instruction through the -march=armv8-a+sb 1579 option. 1580 + Execution and Data Prediction Restriction instructions through 1581 the -march=armv8-a+predres option. 1582 + Speculative Store Bypass Safe instruction through the 1583 -march=armv8-a+ssbs option. This does not require a compiler 1584 option for Arm and thus -march=armv8-a+ssbs is an 1585 AArch64-specific option. 1586 1587 AArch64 specific 1588 1589 * Support has been added for the Arm Neoverse E1 processor 1590 (-mcpu=neoverse-e1). 1591 * The AArch64 port now has support for stack clash protection using 1592 the [60]-fstack-clash-protection option. The probing interval/guard 1593 size can be set by using --param 1594 stack-clash-protection-guard-size=12|16. The value of this 1595 parameter must be in bytes represented as a power of two. The two 1596 supported values for this parameter are 12 (for a 4KiB size, 2^12) 1597 and 16 (for a 64KiB size, 2^16). The default value is 16 (64Kb) and 1598 can be changed at configure time using the flag 1599 --with-stack-clash-protection-guard-size=12|16. 1600 * The option -msign-return-address= has been deprecated. This has 1601 been replaced by the new -mbranch-protection= option. This new 1602 option can now be used to enable the return address signing as well 1603 as the new Branch Target Identification feature of Armv8.5-A 1604 architecture. For more information on the arguments accepted by 1605 this option, please refer to [61]AArch64-Options. 1606 * The following optional extensions to Armv8.5-A architecture are now 1607 supported and only affect the assembler. 1608 + Random Number Generation instructions through the 1609 -march=armv8.5-a+rng option. 1610 + Memory Tagging Extension through the -march=armv8.5-a+memtag 1611 option. 1612 1613 Arm specific 1614 1615 * Support for the deprecated Armv2 and Armv3 architectures and their 1616 variants has been removed. Their corresponding -march values and 1617 the -mcpu options that used these architectures have been removed. 1618 * Support for the Armv5 and Armv5E architectures (which have no known 1619 implementations) has been removed. Note that Armv5T, Armv5TE and 1620 Armv5TEJ architectures remain supported. 1621 * Corrected FPU configurations for Cortex-R7 and Cortex-R8 when using 1622 their respective -mcpu options. 1623 1624 AMD GCN 1625 1626 * A new back end targeting AMD GCN GPUs has been contributed to GCC. 1627 The implementation is currently limited to compiling 1628 single-threaded, stand-alone programs. Future versions will add 1629 support for offloading multi-threaded kernels via OpenMP and 1630 OpenACC. The following devices are supported (GCC identifiers in 1631 parentheses): 1632 + Fiji (fiji). 1633 + Vega 10 (gfx900). 1634 1635 ARC 1636 1637 * LRA is now on by default for the ARC target. This can be controlled 1638 by -mlra. 1639 * Add support for frame code-density and branch-and-index 1640 instructions. 1641 1642 C-SKY 1643 1644 * A new back end targeting C-SKY V2 processors has been contributed 1645 to GCC. 1646 1647 IA-32/x86-64 1648 1649 * Support of Intel MPX (Memory Protection Extensions) has been 1650 removed. 1651 * New ISA extension support for Intel PTWRITE was added to GCC. 1652 PTWRITE intrinsics are available via the -mptwrite compiler switch. 1653 * GCC now supports the Intel CPU named Cascade Lake with AVX512 1654 extensions through -march=cascadelake. The switch enables the 1655 following ISA extensions: AVX512F, AVX512VL, AVX512CD, AVX512BW, 1656 AVX512DQ, AVX512VNNI. 1657 1658 MIPS 1659 1660 * The Loongson loongson-mmi and loongson-ext extensions have been 1661 split from loongson3a: 1662 + loongson-mmi contains the Loongson MMI (MultiMedia extensions 1663 Instructions). 1664 + loongson-ext contains the Loongson EXT (EXTensions 1665 instructions). 1666 * The Loongson EXT2 (EXTensions R2 instructions) are now supported. 1667 + loongson-ext2 contains the Loongson EXT2 instructions. 1668 Command-line options-m[no-]loongson-mmi, -m[no-]loongson-ext, and 1669 -m[no-]loongson-ext2 enable or disable those extensions. 1670 * Support has been added for the following processors (GCC 1671 identifiers in parentheses): 1672 + Loongson 3A1000 (gs464) which enables loongson-mmi, 1673 loongson-ext by default. 1674 + Loongson 3A2000/3A3000 (gs464e) which enables loongson-mmi, 1675 loongson-ext, loongson-ext2 by default. 1676 + Loongson 2K1000 (gs264e) which enables loongson-ext, 1677 loongson-ext2, msa by default. 1678 The GCC identifiers can be used as arguments to the -mcpu and 1679 -mtune options (as in -mcpu=gs464 or -mtune=gs464e) or as arguments 1680 to the equivalent target attributes and pragmas. 1681 1682 OpenRISC 1683 1684 * A new back end targeting OpenRISC processors has been contributed 1685 to GCC. 1686 1687 S/390, System z, IBM z Systems 1688 1689 * Support for the arch13 architecture has been added. When using the 1690 -march=arch13 option, the compiler will generate code making use of 1691 the new instructions introduced with the vector enhancement 1692 facility 2 and the miscellaneous instruction extension facility 2. 1693 The -mtune=arch13 option enables arch13 specific instruction 1694 scheduling without making use of new instructions. 1695 * Builtins for the new vector instructions have been added and can be 1696 enabled using the -mzvector option. 1697 * Support for ESA architecture machines g5 and g6 is deprecated since 1698 GCC 6.1.0 and has been removed now. 1699 * When compiling with -march=z14 or higher GCC emits alignments hints 1700 on the vector load/store instructions (8 or 16 byte). 1701 * Functions now have a default alignment of 16 bytes. This helps with 1702 branch prediction effects. 1703 * -mfentry is now supported. As well as the mcount mechanism the 1704 __fentry__ is called before the function prologue. However, since 1705 just a single instruction is required to call __fentry__ the call 1706 sequence imposes a smaller overhead than mcount (4 instructions). 1707 The produced code is compatible only with newer glibc versions, 1708 which provide the __fentry__ symbol and do not clobber r0 when 1709 resolving lazily bound functions. -mfentry is only supported when 1710 generating 64 bit code and does not work with nested C functions. 1711 * The -mnop-mcount option can be used to emit NOP instructions 1712 instead of an mcount or fentry call stub. 1713 * With the -mrecord-mcount option a __mcount_loc section is generated 1714 containing pointers to each profiling call stub. This is useful for 1715 automatically patching in and out calls. 1716 1717 Operating Systems 1718 1719 Solaris 1720 1721 * g++ now unconditionally enables large file support when compiling 1722 32-bit code. 1723 * Support for the AddressSanitizer and UndefinedBehaviorSanitizer has 1724 been merged from LLVM. For the moment, this only works for 32-bit 1725 code on both SPARC and x86. 1726 * An initial port of the D runtime library has been completed on 1727 Solaris 11/x86. It requires the use of GNU as. Solaris 11/SPARC 1728 support is still work-in-progress. 1729 1730 Windows 1731 1732 * A C++ Microsoft ABI bitfield layout bug, [62]PR87137 has been 1733 fixed. A non-field declaration could cause the current bitfield 1734 allocation unit to be completed, incorrectly placing a following 1735 bitfield into a new allocation unit. The Microsoft ABI is selected 1736 for: 1737 + Mingw targets 1738 + PowerPC, IA-32 or x86-64 targets when the -mms-bitfields 1739 option is specified, or __attribute__((ms_struct)) is used 1740 + SuperH targets when the -mhitachi option is specified, or 1741 __attribute__((renesas)) is used 1742 1743 Improvements for plugin authors 1744 1745 * GCC's diagnostic subsystem now has a way to logically group 1746 together related diagnostics, auto_diagnostic_group. Such 1747 diagnostics will be nested by the output of 1748 [63]-fdiagnostics-format=json. 1749 * GCC now has a set of [64]user experience guidelines for GCC, with 1750 information and advice on implementing new diagnostics. 1751 1752 Other significant improvements 1753 1754 * GCC's internal "selftest" suite now runs for C++ as well as C (in 1755 debug builds of the compiler). 1756 1757 GCC 9.1 1758 1759 This is the [65]list of problem reports (PRs) from GCC's bug tracking 1760 system that are known to be fixed in the 9.1 release. This list might 1761 not be complete (that is, it is possible that some PRs that have been 1762 fixed are not listed here). 1763 1764 GCC 9.2 1765 1766 This is the [66]list of problem reports (PRs) from GCC's bug tracking 1767 system that are known to be fixed in the 9.2 release. This list might 1768 not be complete (that is, it is possible that some PRs that have been 1769 fixed are not listed here). 1770 1771 GCC 9.3 1772 1773 This is the [67]list of problem reports (PRs) from GCC's bug tracking 1774 system that are known to be fixed in the 9.3 release. This list might 1775 not be complete (that is, it is possible that some PRs that have been 1776 fixed are not listed here). 1777 1778 GCC 9.4 1779 1780 This is the [68]list of problem reports (PRs) from GCC's bug tracking 1781 system that are known to be fixed in the 9.4 release. This list might 1782 not be complete (that is, it is possible that some PRs that have been 1783 fixed are not listed here). 1784 1785 Target Specific Changes 1786 1787 AArch64 1788 1789 * The option -moutline-atomics has been added to aid deployment of 1790 the Large System Extensions (LSE) on GNU/Linux systems built with a 1791 baseline architecture targeting Armv8-A. When the option is 1792 specified code is emitted to detect the presence of LSE 1793 instructions at run time and use them for standard atomic 1794 operations. For more information please refer to the documentation. 1795 * GCC now supports the Fujitsu A64FX. The associated -mcpu and -mtune 1796 options are -mcpu=a64fx and -mtune=a64fx respectively. In 1797 particular, -mcpu=a64fx generates code for Armv8.2-A with SVE and 1798 tunes the code for the A64FX. This includes tuning the SVE code, 1799 although by default the code is still length-agnostic and so works 1800 for all SVE implementations. Adding -msve-vector-bits=512 makes the 1801 code specific to 512-bit SVE. 1802 1803 GCC 9.5 1804 1805 This is the [69]list of problem reports (PRs) from GCC's bug tracking 1806 system that are known to be fixed in the 9.5 release. This list might 1807 not be complete (that is, it is possible that some PRs that have been 1808 fixed are not listed here). 1809 1810 1811 For questions related to the use of GCC, please consult these web 1812 pages and the [70]GCC manuals. If that fails, the 1813 [71]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 1814 web pages and the development of GCC are welcome on our developer 1815 list at [72]gcc (a] gcc.gnu.org. All of [73]our lists have public 1816 archives. 1817 1818 Copyright (C) [74]Free Software Foundation, Inc. Verbatim copying and 1819 distribution of this entire article is permitted in any medium, 1820 provided this notice is preserved. 1821 1822 These pages are [75]maintained by the GCC team. Last modified 1823 2023-02-22. 1824 1825 References 1826 1827 1. http://gcc.gnu.org/gcc-9/porting_to.html 1828 2. http://gcc.gnu.org/onlinedocs/index.html#current 1829 3. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88469 1830 4. https://gcc.gnu.org/ml/gcc/2018-10/msg00139.html 1831 5. https://gcc.gnu.org/ml/gcc/2019-04/msg00023.html 1832 6. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90920 1833 7. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-frepo 1834 8. https://gcc.gnu.org/PR90361 1835 9. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Invoking-GCC.html#Invoking-GCC 1836 10. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-flive-patching 1837 11. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fno-diagnostics-show-line-numbers 1838 12. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fno-diagnostics-show-labels 1839 13. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fdiagnostics-format 1840 14. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-falign-functions 1841 15. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-falign-labels 1842 16. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-falign-loops 1843 17. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-falign-jumps 1844 18. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Instrumentation-Options.html#index-fprofile-filter-files 1845 19. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Instrumentation-Options.html#index-fprofile-exclude-files 1846 20. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Developer-Options.html#index-fopt-info 1847 21. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Developer-Options.html#index-fsave-optimization-record 1848 22. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-fipa-stack-alignment 1849 23. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-fipa-reference-addressable 1850 24. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005fexpect_005fwith_005fprobability 1851 25. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005fhas_005fattribute-1 1852 26. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005fspeculation_005fsafe_005fvalue-1 1853 27. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Common-Function-Attributes.html#index-copy-function-attribute 1854 28. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-ftree-switch-conversion 1855 29. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-fprofile-use 1856 30. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-fversion-loops-for-strides 1857 31. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-floop-interchange 1858 32. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-floop-unroll-and-jam 1859 33. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Optimize-Options.html#index-ftree-loop-distribution 1860 34. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Invoking-Gcov.html#Invoking-Gcov 1861 35. https://www.openacc.org/ 1862 36. https://gcc.gnu.org/wiki/OpenACC/Implementation%20Status#status-9 1863 37. https://www.openmp.org/specifications/ 1864 38. https://gcc.gnu.org/ml/gcc-patches/2018-11/msg00628.html 1865 39. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Vector-Extensions.html#index-_005f_005fbuiltin_005fconvertvector 1866 40. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Waddress-of-packed-member 1867 41. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Warray-bounds 1868 42. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wattribute-alias 1869 43. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wformat-overflow 1870 44. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wformat-truncation 1871 45. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wmissing-attributes 1872 46. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wstringop-truncation 1873 47. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wabsolute-value 1874 48. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Wdeprecated-copy 1875 49. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Winit-list-lifetime 1876 50. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Wredundant-move 1877 51. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Wpessimizing-move 1878 52. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-Wclass-conversion 1879 53. http://gcc.gnu.org/projects/cxx-status.html#cxx2a 1880 54. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#index-Wformat 1881 55. https://github.com/oneapi-src/oneTBB 1882 56. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gfortran/Fortran-Dialect-Options.html#index-fdec-include 1883 57. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gfortran/Fortran-Dialect-Options.html#index-fdec 1884 58. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gfortran/BUILTIN-directive.html#BUILTIN-directive 1885 59. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/jit/topics/contexts.html#gcc_jit_context_add_driver_option 1886 60. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Instrumentation-Options.html#index-fstack-protector 1887 61. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/AArch64-Options.html#AArch64-Options 1888 62. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87137 1889 63. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Diagnostic-Message-Formatting-Options.html#index-fdiagnostics-format 1890 64. https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gccint/User-Experience-Guidelines.html 1891 65. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=9.0 1892 66. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=9.2 1893 67. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=9.3 1894 68. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=9.4 1895 69. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=9.5 1896 70. https://gcc.gnu.org/onlinedocs/ 1897 71. mailto:gcc-help (a] gcc.gnu.org 1898 72. mailto:gcc (a] gcc.gnu.org 1899 73. https://gcc.gnu.org/lists.html 1900 74. https://www.fsf.org/ 1901 75. https://gcc.gnu.org/about.html 1902 ====================================================================== 1903 http://gcc.gnu.org/gcc-8/index.html 1904 1905 GCC 8 Release Series 1906 1907 (This release series is no longer supported.) 1908 1909 May 14, 2021 1910 1911 The [1]GNU project and the GCC developers are pleased to announce the 1912 release of GCC 8.5. 1913 1914 This release is a bug-fix release, containing fixes for regressions in 1915 GCC 8.4 relative to previous releases of GCC. 1916 1917 Release History 1918 1919 GCC 8.5 1920 May 14, 2021 ([2]changes, [3]documentation) 1921 1922 GCC 8.4 1923 Mar 4, 2020 ([4]changes, [5]documentation) 1924 1925 GCC 8.3 1926 Feb 22, 2019 ([6]changes, [7]documentation) 1927 1928 GCC 8.2 1929 Jul 26, 2018 ([8]changes, [9]documentation) 1930 1931 GCC 8.1 1932 May 2, 2018 ([10]changes, [11]documentation) 1933 1934 References and Acknowledgements 1935 1936 GCC used to stand for the GNU C Compiler, but since the compiler 1937 supports several other languages aside from C, it now stands for the 1938 GNU Compiler Collection. 1939 1940 A list of [12]successful builds is updated as new information becomes 1941 available. 1942 1943 The GCC developers would like to thank the numerous people that have 1944 contributed new features, improvements, bug fixes, and other changes as 1945 well as test results to GCC. This [13]amazing group of volunteers is 1946 what makes GCC successful. 1947 1948 For additional information about GCC please refer to the [14]GCC 1949 project web site or contact the [15]GCC development mailing list. 1950 1951 To obtain GCC please use [16]our mirror sites or [17]our version 1952 control system. 1953 1954 1955 For questions related to the use of GCC, please consult these web 1956 pages and the [18]GCC manuals. If that fails, the 1957 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 1958 web pages and the development of GCC are welcome on our developer 1959 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 1960 archives. 1961 1962 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 1963 distribution of this entire article is permitted in any medium, 1964 provided this notice is preserved. 1965 1966 These pages are [23]maintained by the GCC team. Last modified 1967 2022-10-26. 1968 1969 References 1970 1971 1. http://www.gnu.org/ 1972 2. http://gcc.gnu.org/gcc-8/changes.html 1973 3. http://gcc.gnu.org/onlinedocs/8.5.0/ 1974 4. http://gcc.gnu.org/gcc-8/changes.html 1975 5. http://gcc.gnu.org/onlinedocs/8.4.0/ 1976 6. http://gcc.gnu.org/gcc-8/changes.html 1977 7. http://gcc.gnu.org/onlinedocs/8.3.0/ 1978 8. http://gcc.gnu.org/gcc-8/changes.html 1979 9. http://gcc.gnu.org/onlinedocs/8.2.0/ 1980 10. http://gcc.gnu.org/gcc-8/changes.html 1981 11. http://gcc.gnu.org/onlinedocs/8.1.0/ 1982 12. http://gcc.gnu.org/gcc-8/buildstat.html 1983 13. http://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Contributors.html 1984 14. http://gcc.gnu.org/index.html 1985 15. mailto:gcc (a] gcc.gnu.org 1986 16. http://gcc.gnu.org/mirrors.html 1987 17. http://gcc.gnu.org/git.html 1988 18. https://gcc.gnu.org/onlinedocs/ 1989 19. mailto:gcc-help (a] gcc.gnu.org 1990 20. mailto:gcc (a] gcc.gnu.org 1991 21. https://gcc.gnu.org/lists.html 1992 22. https://www.fsf.org/ 1993 23. https://gcc.gnu.org/about.html 1994 ====================================================================== 1995 http://gcc.gnu.org/gcc-8/changes.html 1996 1997 GCC 8 Release Series 1998 Changes, New Features, and Fixes 1999 2000 This page is a "brief" summary of some of the huge number of 2001 improvements in GCC 8. You may also want to check out our [1]Porting to 2002 GCC 8 page and the [2]full GCC documentation. 2003 2004 Caveats 2005 2006 * Support for the obsolete SDB/coff debug info format has been 2007 removed. The option -gcoff no longer does anything. 2008 * The Cilk+ extensions to the C and C++ languages have been removed. 2009 * The MPX extensions to the C and C++ languages have been deprecated 2010 and will be removed in a future release. 2011 * The extension allowing arithmetic on std::atomic<void*> and types 2012 like std::atomic<R(*)()> has been deprecated. 2013 * The non-standard C++0x std::copy_exception function was removed. 2014 std::make_exception_ptr should be used instead. 2015 * Support for the powerpc*-*-*spe* target ports which have been 2016 recently unmaintained and untested in GCC has been declared 2017 obsolete in GCC 8 as [3]announced. Unless there is activity to 2018 revive them, the next release of GCC will have their sources 2019 permanently removed. 2020 2021 General Improvements 2022 2023 * Inter-procedural optimization improvements: 2024 + Reworked run-time estimation metrics leading to more realistic 2025 guesses driving inliner and cloning heuristics. 2026 + The ipa-pure-const pass is extended to propagate the malloc 2027 attribute, and the corresponding warning option 2028 -Wsuggest-attribute=malloc emits a diagnostic for functions 2029 which can be annotated with the malloc attribute. 2030 * Profile driven optimization improvements: 2031 + New infrastructure for representing profiles (both statically 2032 guessed and profile feedback) which allows propagation of 2033 additional information about the reliability of the profile. 2034 + A number of improvements in the profile updating code solving 2035 problems found by new verification code. 2036 + Static detection of code which is not executed in a valid run 2037 of the program. This includes paths which trigger undefined 2038 behavior as well as calls to functions declared with the cold 2039 attribute. Newly the noreturn attribute does not imply all 2040 effects of cold to differentiate between exit (which is 2041 noreturn) and abort (which is in addition not executed in 2042 valid runs). 2043 + -freorder-blocks-and-partition, a pass splitting function 2044 bodies into hot and cold regions, is now enabled by default at 2045 -O2 and higher for x86 and x86-64. 2046 * Link-time optimization improvements: 2047 + We have significantly improved debug information on ELF 2048 targets using DWARF by properly preserving language-specific 2049 information. This allows for example the libstdc++ 2050 pretty-printers to work with LTO optimized executables. 2051 * A new option -fcf-protection=[full|branch|return|none] is 2052 introduced to perform code instrumentation to increase program 2053 security by checking that target addresses of control-flow transfer 2054 instructions (such as indirect function call, function return, 2055 indirect jump) are valid. Currently the instrumentation is 2056 supported on x86 GNU/Linux targets only. See the user guide for 2057 further information about the option syntax and section "New 2058 Targets and Target Specific Improvements" for IA-32/x86-64 for more 2059 details. 2060 * The -gcolumn-info option is now enabled by default. It includes 2061 column information in addition to just filenames and line numbers 2062 in DWARF debugging information. 2063 * The polyhedral-based loop nest optimization pass 2064 -floop-nest-optimize has been overhauled. It's still considered 2065 experimental and may not result in any runtime improvements. 2066 * Two new classical loop nest optimization passes have been added. 2067 -floop-unroll-and-jam performs outer loop unrolling and fusing of 2068 the inner loop copies. -floop-interchange exchanges loops in a loop 2069 nest to improve data locality. Both passes are enabled by default 2070 at -O3 and above. 2071 * The classic loop nest optimization pass -ftree-loop-distribution 2072 has been improved and enabled by default at -O3 and above. It 2073 supports loop nest distribution in some restricted scenarios; it 2074 also supports cancellable innermost loop distribution with loop 2075 versioning under run-time alias checks. 2076 * The new option -fstack-clash-protection causes the compiler to 2077 insert probes whenever stack space is allocated statically or 2078 dynamically to reliably detect stack overflows and thus mitigate 2079 the attack vector that relies on jumping over a stack guard page as 2080 provided by the operating system. 2081 * A new pragma GCC unroll has been implemented in the C family of 2082 languages, as well as Fortran and Ada, so as to make it possible 2083 for the user to have a finer-grained control over the loop 2084 unrolling optimization. 2085 * GCC has been enhanced to detect more instances of meaningless or 2086 mutually exclusive attribute specifications and handle such 2087 conflicts more consistently. Mutually exclusive attribute 2088 specifications are ignored with a warning regardless of whether 2089 they appear on the same declaration or on distinct declarations of 2090 the same entity. For example, because the noreturn attribute on the 2091 second declaration below is mutually exclusive with the malloc 2092 attribute on the first, it is ignored and a warning is issued. 2093 > 2094 void* __attribute__ ((malloc)) f (unsigned); 2095 void* __attribute__ ((noreturn)) f (unsigned); 2096 2097 warning: ignoring attribute 'noreturn' because it conflicts with attribute 2098 'malloc' [-Wattributes] 2099 * The gcov tool can distinguish functions that begin on a same line 2100 in a source file. This can be a different template instantiation or 2101 a class constructor: 2102 2103 File 'ins.C' 2104 Lines executed:100.00% of 8 2105 Creating 'ins.C.gcov' 2106 2107 -: 0:Source:ins.C 2108 -: 0:Graph:ins.gcno 2109 -: 0:Data:ins.gcda 2110 -: 0:Runs:1 2111 -: 0:Programs:1 2112 -: 1:template<class T> 2113 -: 2:class Foo 2114 -: 3:{ 2115 -: 4: public: 2116 2: 5: Foo(): b (1000) {} 2117 ------------------ 2118 Foo<char>::Foo(): 2119 1: 5: Foo(): b (1000) {} 2120 ------------------ 2121 Foo<int>::Foo(): 2122 1: 5: Foo(): b (1000) {} 2123 ------------------ 2124 2: 6: void inc () { b++; } 2125 ------------------ 2126 Foo<char>::inc(): 2127 1: 6: void inc () { b++; } 2128 ------------------ 2129 Foo<int>::inc(): 2130 1: 6: void inc () { b++; } 2131 ------------------ 2132 -: 7: 2133 -: 8: private: 2134 -: 9: int b; 2135 -: 10:}; 2136 -: 11: 2137 1: 12:int main(int argc, char **argv) 2138 -: 13:{ 2139 1: 14: Foo<int> a; 2140 1: 15: Foo<char> b; 2141 -: 16: 2142 1: 17: a.inc (); 2143 1: 18: b.inc (); 2144 1: 19:} 2145 2146 * The gcov tool has more accurate numbers for execution of lines in a 2147 source file. 2148 * The gcov tool can use TERM colors to provide more readable output. 2149 * AddressSanitizer gained a new pair of sanitization options, 2150 -fsanitize=pointer-compare and -fsanitize=pointer-subtract, which 2151 warn about subtraction (or comparison) of pointers that point to a 2152 different memory object: 2153 2154 int 2155 main () 2156 { 2157 /* Heap allocated memory. */ 2158 char *heap1 = (char *)__builtin_malloc (42); 2159 char *heap2 = (char *)__builtin_malloc (42); 2160 if (heap1 > heap2) 2161 return 1; 2162 2163 return 0; 2164 } 2165 2166 ==17465==ERROR: AddressSanitizer: invalid-pointer-pair: 0x604000000010 0x6040000 2167 00050 2168 #0 0x40070f in main /tmp/pointer-compare.c:7 2169 #1 0x7ffff6a72a86 in __libc_start_main (/lib64/libc.so.6+0x21a86) 2170 #2 0x400629 in _start (/tmp/a.out+0x400629) 2171 2172 0x604000000010 is located 0 bytes inside of 42-byte region [0x604000000010,0x604 2173 00000003a) 2174 allocated by thread T0 here: 2175 #0 0x7ffff6efb390 in __interceptor_malloc ../../../../libsanitizer/asan/asan 2176 _malloc_linux.cc:86 2177 #1 0x4006ea in main /tmp/pointer-compare.c:5 2178 #2 0x7ffff6a72a86 in __libc_start_main (/lib64/libc.so.6+0x21a86) 2179 2180 0x604000000050 is located 0 bytes inside of 42-byte region [0x604000000050,0x604 2181 00000007a) 2182 allocated by thread T0 here: 2183 #0 0x7ffff6efb390 in __interceptor_malloc ../../../../libsanitizer/asan/asan 2184 _malloc_linux.cc:86 2185 #1 0x4006f8 in main /tmp/pointer-compare.c:6 2186 #2 0x7ffff6a72a86 in __libc_start_main (/lib64/libc.so.6+0x21a86) 2187 2188 SUMMARY: AddressSanitizer: invalid-pointer-pair /tmp/pointer-compare.c:7 in main 2189 2190 * The store merging pass has been enhanced to handle bit-fields and 2191 not just constant stores, but also data copying from adjacent 2192 memory locations into other adjacent memory locations, including 2193 bitwise logical operations on the data. The pass can also handle 2194 byte swapping into memory locations. 2195 * The undefined behavior sanitizer gained two new options included in 2196 -fsanitize=undefined: -fsanitize=builtin which diagnoses at run 2197 time invalid arguments to __builtin_clz or __builtin_ctz prefixed 2198 builtins, and -fsanitize=pointer-overflow which performs cheap run 2199 time tests for pointer wrapping. 2200 * A new attribute no_sanitize can be applied to functions to instruct 2201 the compiler not to do sanitization of the options provided as 2202 arguments to the attribute. Acceptable values for no_sanitize match 2203 those acceptable by the -fsanitize command-line option. 2204 2205 void __attribute__ ((no_sanitize ("alignment", "object-size"))) 2206 f () { /* Do something. */; } 2207 2208 New Languages and Language specific improvements 2209 2210 Ada 2211 2212 * For its internal exception handling used on the host for error 2213 recovery in the front-end, the compiler now relies on the native 2214 exception handling mechanism of the host platform, which should be 2215 more efficient than the former mechanism. 2216 2217 BRIG (HSAIL) 2218 2219 In this release cycle, the focus for the BRIGFE was on stabilization 2220 and performance improvements. Also a couple of completely new features 2221 were added. 2222 * Improved support for function and module scope group segment 2223 variables. PRM specs define function and module scope group segment 2224 variables as an experimental feature. However, PRM test suite uses 2225 them. Now group segment is handled by separate book keeping of 2226 module scope and function (kernel) offsets. Each function has a 2227 "frame" in the group segment offset to which is given as an 2228 argument, similar to traditional call stack frame handling. 2229 * Reduce the number of type conversions due to the untyped HSAIL 2230 registers. Instead of always representing the HSAIL's untyped 2231 registers as unsigned int, the gccbrig now pre-analyzes the BRIG 2232 code and builds the register variables as a type used the most when 2233 storing or reading data to/from each register. This reduces the 2234 number of total casts which cannot be always optimized away. 2235 * Support for BRIG_KIND_NONE directives. 2236 * Made -O3 the default optimization level for BRIGFE. 2237 * Fixed illegal addresses generated from address expressions which 2238 refer only to offset 0. 2239 * Fixed a bug with reg+offset addressing on 32b segments. In 'large' 2240 mode, the offset is treated as 32-bit unless it's in global, 2241 read-only or kernarg address space. 2242 * Fixed a crash caused sometimes by calls with more than 4 arguments. 2243 * Fixed a mis-execution issue with kernels that have both unexpanded 2244 ID functions and calls to subfunctions. 2245 * Treat HSAIL barrier builtins as setjmp/longjump style functions to 2246 avoid illegal optimizations. 2247 * Ensure per WI copies of private variables are aligned correctly. 2248 * libhsail-rt: Assume the host runtime allocates the work group 2249 memory. 2250 2251 C family 2252 2253 * New command-line options have been added for the C and C++ 2254 compilers: 2255 + [4]-Wmultistatement-macros warns about unsafe macros expanding 2256 to multiple statements used as a body of a statement such as 2257 if, else, while, switch, or for. 2258 + [5]-Wstringop-truncation warns for calls to bounded string 2259 manipulation functions such as strncat, strncpy, and stpncpy 2260 that might either truncate the copied string or leave the 2261 destination unchanged. For example, the following call to 2262 strncat is diagnosed because it appends just three of the four 2263 characters from the source string. 2264 void append (char *buf, size_t bufsize) 2265 { 2266 strncat (buf, ".txt", 3); 2267 } 2268 warning: 'strncat' output truncated copying 3 bytes from a string of length 4 [- 2269 Wstringop-truncation] 2270 Similarly, in the following example, the call to strncpy 2271 specifies the size of the destination buffer as the bound. If 2272 the length of the source string is equal to or greater than 2273 this size the result of the copy will not be NUL-terminated. 2274 Therefore, the call is also diagnosed. To avoid the warning, 2275 specify sizeof buf - 1 as the bound and set the last element 2276 of the buffer to NUL. 2277 void copy (const char *s) 2278 { 2279 char buf[80]; 2280 strncpy (buf, s, sizeof buf); 2281 ... 2282 } 2283 warning: 'strncpy' specified bound 80 equals destination size [-Wstringop-trunca 2284 tion] 2285 The -Wstringop-truncation option is included in -Wall. 2286 Note that due to GCC bug [6]82944, defining strncat, strncpy, 2287 or stpncpy as a macro in a system header as some 2288 implementations do, suppresses the warning. 2289 + [7]-Wif-not-aligned controls warnings issued in response to 2290 invalid uses of objects declared with attribute 2291 [8]warn_if_not_aligned. 2292 The -Wif-not-aligned option is included in -Wall. 2293 + [9]-Wmissing-attributes warns when a declaration of a function 2294 is missing one or more attributes that a related function is 2295 declared with and whose absence may adversely affect the 2296 correctness or efficiency of generated code. For example, in 2297 C++, the warning is issued when an explicit specialization of 2298 a primary template declared with attribute alloc_align, 2299 alloc_size, assume_aligned, format, format_arg, malloc, or 2300 nonnull is declared without it. Attributes deprecated, error, 2301 and warning suppress the warning. 2302 The -Wmissing-attributes option is included in -Wall. 2303 + [10]-Wpacked-not-aligned warns when a struct or union declared 2304 with attribute packed defines a member with an explicitly 2305 specified alignment greater than 1. Such a member will wind up 2306 under-aligned. For example, a warning will be issued for the 2307 definition of struct A in the following: 2308 struct __attribute__ ((aligned (8))) 2309 S8 { char a[8]; }; 2310 2311 struct __attribute__ ((packed)) A 2312 { 2313 struct S8 s8; 2314 }; 2315 warning: alignment 1 of 'struct S' is less than 8 [-Wpacked-not-aligned] 2316 The -Wpacked-not-aligned option is included in -Wall. 2317 + -Wcast-function-type warns when a function pointer is cast to 2318 an incompatible function pointer. This warning is enabled by 2319 -Wextra. 2320 + -Wsizeof-pointer-div warns for suspicious divisions of the 2321 size of a pointer by the size of the elements it points to, 2322 which looks like the usual way to compute the array size but 2323 won't work out correctly with pointers. This warning is 2324 enabled by -Wall. 2325 + -Wcast-align=strict warns whenever a pointer is cast such that 2326 the required alignment of the target is increased. For 2327 example, warn if a char * is cast to an int * regardless of 2328 the target machine. 2329 + -fprofile-abs-path creates absolute path names in the .gcno 2330 files. This allows gcov to find the correct sources in 2331 projects where compilations occur with different working 2332 directories. 2333 * -fno-strict-overflow is now mapped to -fwrapv -fwrapv-pointer and 2334 signed integer overflow is now undefined by default at all 2335 optimization levels. Using -fsanitize=signed-integer-overflow is 2336 now the preferred way to audit code, -Wstrict-overflow is 2337 deprecated. 2338 * The [11]-Warray-bounds option has been improved to detect more 2339 instances of out-of-bounds array indices and pointer offsets. For 2340 example, negative or excessive indices into flexible array members 2341 and string literals are detected. 2342 * The [12]-Wrestrict option introduced in GCC 7 has been enhanced to 2343 detect many more instances of overlapping accesses to objects via 2344 restrict-qualified arguments to standard memory and string 2345 manipulation functions such as memcpy and strcpy. For example, the 2346 strcpy call in the function below attempts to truncate the string 2347 by replacing its initial characters with the last four. However, 2348 because the function writes the terminating NUL into a[4], the 2349 copies overlap and the call is diagnosed. 2350 void f (void) 2351 { 2352 char a[] = "abcd1234"; 2353 strcpy (a, a + 4); 2354 ... 2355 } 2356 warning: 'strcpy' accessing 5 bytes at offsets 0 and 4 overlaps 1 byte at offset 2357 4 [-Wrestrict] 2358 The -Wrestrict option is included in -Wall. 2359 * Several optimizer enhancements have enabled improvements to the 2360 [13]-Wformat-overflow and [14]-Wformat-truncation options. The 2361 warnings detect more instances of buffer overflow and truncation 2362 than in GCC 7 and are better at avoiding certain kinds of false 2363 positives. 2364 * When reporting mismatching argument types at a function call, the C 2365 and C++ compilers now underline both the argument and the pertinent 2366 parameter in the declaration. 2367 $ gcc arg-type-mismatch.cc 2368 arg-type-mismatch.cc: In function 'int caller(int, int, float)': 2369 arg-type-mismatch.cc:5:24: error: invalid conversion from 'int' to 'const char*' 2370 [-fpermissive] 2371 return callee(first, second, third); 2372 ^~~~~~ 2373 arg-type-mismatch.cc:1:40: note: initializing argument 2 of 'int callee(int, c 2374 onst char*, float)' 2375 extern int callee(int one, const char *two, float three); 2376 ~~~~~~~~~~~~^~~ 2377 2378 * When reporting on unrecognized identifiers, the C and C++ compilers 2379 will now emit fix-it hints suggesting #include directives for 2380 various headers in the C and C++ standard libraries. 2381 $ gcc incomplete.c 2382 incomplete.c: In function 'test': 2383 incomplete.c:3:10: error: 'NULL' undeclared (first use in this function) 2384 return NULL; 2385 ^~~~ 2386 incomplete.c:3:10: note: 'NULL' is defined in header '<stddef.h>'; did you forge 2387 t to '#include <stddef.h>'? 2388 incomplete.c:1:1: 2389 +#include <stddef.h> 2390 const char *test(void) 2391 incomplete.c:3:10: 2392 return NULL; 2393 ^~~~ 2394 incomplete.c:3:10: note: each undeclared identifier is reported only once for ea 2395 ch function it appears in 2396 2397 $ gcc incomplete.cc 2398 incomplete.cc:1:6: error: 'string' in namespace 'std' does not name a type 2399 std::string s("hello world"); 2400 ^~~~~~ 2401 incomplete.cc:1:1: note: 'std::string' is defined in header '<string>'; did you 2402 forget to '#include <string>'? 2403 +#include <string> 2404 std::string s("hello world"); 2405 ^~~ 2406 2407 * The C and C++ compilers now use more intuitive locations when 2408 reporting on missing semicolons, and offer fix-it hints: 2409 $ gcc t.c 2410 t.c: In function 'test': 2411 t.c:3:12: error: expected ';' before '}' token 2412 return 42 2413 ^ 2414 ; 2415 } 2416 ~ 2417 2418 * When reporting on missing '}' and ')' tokens, the C and C++ 2419 compilers will now highlight the corresponding '{' and '(' token, 2420 issuing a 'note' if it's on a separate line: 2421 $ gcc unclosed.c 2422 unclosed.c: In function 'log_when_out_of_range': 2423 unclosed.c:12:50: error: expected ')' before '{' token 2424 && (temperature < MIN || temperature > MAX) { 2425 ^~ 2426 ) 2427 unclosed.c:11:6: note: to match this '(' 2428 if (logging_enabled && check_range () 2429 ^ 2430 2431 or highlighting it directly if it's on the same line: 2432 $ gcc unclosed-2.c 2433 unclosed-2.c: In function 'test': 2434 unclosed-2.c:8:45: error: expected ')' before '{' token 2435 if (temperature < MIN || temperature > MAX { 2436 ~ ^~ 2437 ) 2438 2439 They will also emit fix-it hints. 2440 2441 C++ 2442 2443 * GCC 8 (-fabi-version=12) has a couple of corrections to the calling 2444 convention, which changes the ABI for some uncommon code: 2445 + Passing an empty class as an argument now takes up no space on 2446 x86_64, as required by the psABI. 2447 + Passing or returning a class with only deleted copy and move 2448 constructors now uses the same calling convention as a class 2449 with a non-trivial copy or move constructor. This only affects 2450 C++17 mode, as in earlier standards passing or returning such 2451 a class was impossible. 2452 + WARNING: In GCC 8.1 the second change mistakenly also affects 2453 classes with a deleted copy constructor and defaulted trivial 2454 move constructor (bug [15]c++/86094). This issue is fixed in 2455 GCC 8.2 (-fabi-version=13). 2456 You can test whether these changes affect your code with -Wabi=11 2457 (or -Wabi=12 in GCC 8.2 for the third issue); if these changes are 2458 problematic for your project, the GCC 7 ABI can be selected with 2459 -fabi-version=11. 2460 * The value of the C++11 alignof operator has been corrected to match 2461 C _Alignof (minimum alignment) rather than GNU __alignof__ 2462 (preferred alignment); on ia32 targets this means that 2463 alignof(double) is now 4 rather than 8. Code that wants the 2464 preferred alignment should use __alignof__ instead. 2465 * New command-line options have been added for the C++ compiler to 2466 control warnings: 2467 + [16]-Wclass-memaccess warns when objects of non-trivial class 2468 types are manipulated in potentially unsafe ways by raw memory 2469 functions such as memcpy, or realloc. The warning helps detect 2470 calls that bypass user-defined constructors or copy-assignment 2471 operators, corrupt virtual table pointers, data members of 2472 const-qualified types or references, or member pointers. The 2473 warning also detects calls that would bypass access controls 2474 to data members. For example, a call such as: 2475 memcpy (&std::cout, &std::cerr, sizeof std::cout); 2476 results in 2477 warning: 'void* memcpy(void*, const void*, long unsigned int)' writing t 2478 o an object of type 'std::ostream' {aka 'class std::basic_ostream<char>'} with n 2479 o trivial copy-assignment [-Wclass-memaccess] 2480 The -Wclass-memaccess option is included in -Wall. 2481 * The C++ front end has experimental support for some of the upcoming 2482 C++2a draft features with the -std=c++2a or -std=gnu++2a flags, 2483 including designated initializers, default member initializers for 2484 bit-fields, __VA_OPT__ (except that #__VA_OPT__ is unsupported), 2485 lambda [=, this] captures, etc. For a full list of new features, 2486 see [17]the C++ status page. 2487 * When reporting on attempts to access private fields of a class or 2488 struct, the C++ compiler will now offer fix-it hints showing how to 2489 use an accessor function to get at the field in question, if one 2490 exists. 2491 $ gcc accessor.cc 2492 accessor.cc: In function 'void test(foo*)': 2493 accessor.cc:12:12: error: 'double foo::m_ratio' is private within this context 2494 if (ptr->m_ratio >= 0.5) 2495 ^~~~~~~ 2496 accessor.cc:7:10: note: declared private here 2497 double m_ratio; 2498 ^~~~~~~ 2499 accessor.cc:12:12: note: field 'double foo::m_ratio' can be accessed via 'double 2500 foo::get_ratio() const' 2501 if (ptr->m_ratio >= 0.5) 2502 ^~~~~~~ 2503 get_ratio() 2504 2505 * The C++ compiler can now give you a hint if you use a macro before 2506 it was defined (e.g. if you mess up the order of your #include 2507 directives): 2508 $ gcc ordering.cc 2509 ordering.cc:2:24: error: expected ';' at end of member declaration 2510 virtual void clone() const OVERRIDE { } 2511 ^~~~~ 2512 ; 2513 ordering.cc:2:30: error: 'OVERRIDE' does not name a type 2514 virtual void clone() const OVERRIDE { } 2515 ^~~~~~~~ 2516 ordering.cc:2:30: note: the macro 'OVERRIDE' had not yet been defined 2517 In file included from ordering.cc:5: 2518 c++11-compat.h:2: note: it was later defined here 2519 #define OVERRIDE override 2520 2521 2522 * The -Wold-style-cast diagnostic can now emit fix-it hints telling 2523 you when you can use a static_cast, const_cast, or 2524 reinterpret_cast. 2525 $ gcc -c old-style-cast-fixits.cc -Wold-style-cast 2526 old-style-cast-fixits.cc: In function 'void test(void*)': 2527 old-style-cast-fixits.cc:5:19: warning: use of old-style cast to 'struct foo*' [ 2528 -Wold-style-cast] 2529 foo *f = (foo *)ptr; 2530 ^~~ 2531 ---------- 2532 static_cast<foo *> (ptr) 2533 2534 * When reporting on problems within extern "C" linkage 2535 specifications, the C++ compiler will now display the location of 2536 the start of the extern "C". 2537 $ gcc -c extern-c.cc 2538 extern-c.cc:3:1: error: template with C linkage 2539 template <typename T> void test (void); 2540 ^~~~~~~~ 2541 In file included from extern-c.cc:1: 2542 unclosed.h:1:1: note: 'extern "C"' linkage started here 2543 extern "C" { 2544 ^~~~~~~~~~ 2545 extern-c.cc:3:39: error: expected '}' at end of input 2546 template <typename T> void test (void); 2547 ^ 2548 In file included from extern-c.cc:1: 2549 unclosed.h:1:12: note: to match this '{' 2550 extern "C" { 2551 ^ 2552 2553 * When reporting on mismatching template types, the C++ compiler will 2554 now use color to highlight the mismatching parts of the template, 2555 and will elide the parameters that are common between two 2556 mismatching templates, printing [...] instead: 2557 $ gcc templates.cc 2558 templates.cc: In function 'void test()': 2559 templates.cc:9:8: error: could not convert 'vector<double>()' from 'vector<doubl 2560 e>' to 'vector<int>' 2561 fn_1(vector<double> ()); 2562 ^~~~~~~~~~~~~~~~~ 2563 templates.cc:10:8: error: could not convert 'map<int, double>()' from 'map<[...] 2564 ,double>' to 'map<[...],int>' 2565 fn_2(map<int, double>()); 2566 ^~~~~~~~~~~~~~~~~~ 2567 2568 Those [...] elided parameters can be seen using -fno-elide-type: 2569 $ gcc templates.cc -fno-elide-type 2570 templates.cc: In function 'void test()': 2571 templates.cc:9:8: error: could not convert 'vector<double>()' from 'vector<doubl 2572 e>' to 'vector<int>' 2573 fn_1(vector<double> ()); 2574 ^~~~~~~~~~~~~~~~~ 2575 templates.cc:10:8: error: could not convert 'map<int, double>()' from 'map<int,d 2576 ouble>' to 'map<int,int>' 2577 fn_2(map<int, double>()); 2578 ^~~~~~~~~~~~~~~~~~ 2579 2580 The C++ compiler has also gained an option 2581 -fdiagnostics-show-template-tree which visualizes such mismatching 2582 templates in a hierarchical form: 2583 $ gcc templates-2.cc -fdiagnostics-show-template-tree 2584 templates-2.cc: In function 'void test()': 2585 templates-2.cc:9:8: error: could not convert 'vector<double>()' from 'vector<dou 2586 ble>' to 'vector<int>' 2587 vector< 2588 [double != int]> 2589 fn_1(vector<double> ()); 2590 ^~~~~~~~~~~~~~~~~ 2591 templates-2.cc:10:8: error: could not convert 'map<map<int, vector<double> >, ve 2592 ctor<double> >()' from 'map<map<[...],vector<double>>,vector<double>>' to 'map<m 2593 ap<[...],vector<float>>,vector<float>>' 2594 map< 2595 map< 2596 [...], 2597 vector< 2598 [double != float]>>, 2599 vector< 2600 [double != float]>> 2601 fn_2(map<map<int, vector<double>>, vector<double>> ()); 2602 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2603 2604 which again works with -fno-elide-type: 2605 $ gcc templates-2.cc -fdiagnostics-show-template-tree -fno-elide-type 2606 templates-2.cc: In function 'void test()': 2607 templates-2.cc:9:8: error: could not convert 'vector<double>()' from 'vector<dou 2608 ble>' to 'vector<int>' 2609 vector< 2610 [double != int]> 2611 fn_1(vector<double> ()); 2612 ^~~~~~~~~~~~~~~~~ 2613 templates-2.cc:10:8: error: could not convert 'map<map<int, vector<double> >, ve 2614 ctor<double> >()' from 'map<map<int,vector<double>>,vector<double>>' to 'map<map 2615 <int,vector<float>>,vector<float>>' 2616 map< 2617 map< 2618 int, 2619 vector< 2620 [double != float]>>, 2621 vector< 2622 [double != float]>> 2623 fn_2(map<map<int, vector<double>>, vector<double>> ()); 2624 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2625 2626 * Flowing off the end of a non-void function is considered 2627 unreachable and may be subject to optimization on that basis. As a 2628 result of this change, -Wreturn-type warnings are enabled by 2629 default for C++. 2630 2631 Runtime Library (libstdc++) 2632 2633 * Improved experimental support for C++17, including the following 2634 features: 2635 + Deduction guides to support class template argument deduction. 2636 + std::filesystem implementation. 2637 + std::char_traits<char> and std::char_traits<wchar_t> are 2638 usable in constant expressions. 2639 + std::to_chars and std::from_chars (for integers only, not for 2640 floating point types). 2641 * Experimental support for C++2a: std::to_address (thanks to Glen 2642 Fernandes) and std::endian. 2643 * On GNU/Linux, std::random_device::entropy() accesses the kernel's 2644 entropy count for the random device, if known (thanks to Xi 2645 Ruoyao). 2646 * Support for std::experimental::source_location. 2647 * AddressSanitizer integration for std::vector, detecting 2648 out-of-range accesses to the unused capacity of a vector. 2649 * Extensions __gnu_cxx::airy_ai and __gnu_cxx::airy_bi added to the 2650 Mathematical Special Functions. 2651 2652 Fortran 2653 2654 * The main version of libfortran has been changed to 5. 2655 * Parameterized derived types, a major feature of Fortran 2003, have 2656 been implemented. 2657 * Partial support is provided for Fortran 2018 teams, which are 2658 hierarchical subsets of images that execute independently of other 2659 image subsets. 2660 * The maximum rank for arrays has been increased to 15, conforming to 2661 the Fortran 2008 standard. 2662 * Transformational intrinsics are now fully supported in 2663 initialization expressions. 2664 * New flag -fc-prototypes to write C prototypes for BIND(C) 2665 procedures and variables. 2666 * If -fmax-stack-var-size is honored if given together with -Ofast, 2667 -fstack-arrays is no longer set in that case. 2668 * New options -fdefault-real-16 and -fdefault-real-10 to control the 2669 default kind of REAL variables. 2670 * A warning is now issued if an array subscript inside a DO loop 2671 could lead to an out-of-bounds-access. The new option 2672 -Wdo-subscript, enabled by -Wextra, warns about this even if the 2673 compiler can not prove that the code will be executed. 2674 * The Fortran front end now attempts to interchange loops if it is 2675 deemed profitable. So far, this is restricted to FORALL and DO 2676 CONCURRENT statements with multiple indices. This behavior be 2677 controlled with the new flag -ffrontend-loop-interchange, which is 2678 enabled with optimization by default. The 2679 -Wfrontend-loop-interchange option warns about such occurrences. 2680 * When an actual argument contains too few elements for a dummy 2681 argument, an error is now issued. The -std=legacy option can be 2682 used to still compile such code. 2683 * The RECL= argument to OPEN and INQUIRE statements now allows 64-bit 2684 integers, making records larger than 2GiB possible. 2685 * The GFORTRAN_DEFAULT_RECL environment variable no longer has any 2686 effect. The record length for preconnected units is now larger than 2687 any practical limit, same as for sequential access units opened 2688 without an explicit RECL= specifier. 2689 * Character variables longer than HUGE(0) elements are now possible 2690 on 64-bit targets. Note that this changes the procedure call ABI 2691 for all procedures with character arguments on 64-bit targets, as 2692 the type of the hidden character length argument has changed. The 2693 hidden character length argument is now of type INTEGER(C_SIZE_T). 2694 * Partial support is provided for Fortran 2018 teams, which are 2695 hierarchical subsets of images that execute independently of other 2696 image subsets. 2697 2698 Go 2699 2700 * GCC 8 provides a complete implementation of the Go 1.10.1 user 2701 packages. 2702 * The garbage collector is now fully concurrent. As before, values 2703 stored on the stack are scanned conservatively, but value stored in 2704 the heap are scanned precisely. 2705 * Escape analysis is fully implemented and enabled by default in the 2706 Go front end. This significantly reduces the number of heap 2707 allocations by allocating values on the stack instead. 2708 2709 libgccjit 2710 2711 The libgccjit API gained four new entry points: 2712 * [18]gcc_jit_type_get_vector and 2713 * [19]gcc_jit_context_new_rvalue_from_vector for working with 2714 vectors, 2715 * [20]gcc_jit_type_get_aligned 2716 * [21]gcc_jit_function_get_address 2717 2718 The C code generated by [22]gcc_jit_context_dump_reproducer_to_file is 2719 now easier-to-read. 2720 2721 New Targets and Target Specific Improvements 2722 2723 AArch64 2724 2725 * The Armv8.4-A architecture is now supported. It can be used by 2726 specifying the -march=armv8.4-a option. 2727 * The Dot Product instructions are now supported as an optional 2728 extension to the Armv8.2-A architecture and newer and are mandatory 2729 on Armv8.4-A. The extension can be used by specifying the +dotprod 2730 architecture extension. E.g. -march=armv8.2-a+dotprod. 2731 * The Armv8-A +crypto extension has now been split into two 2732 extensions for finer grained control: 2733 + +aes which contains the Armv8-A AES crytographic instructions. 2734 + +sha2 which contains the Armv8-A SHA2 and SHA1 cryptographic 2735 instructions. 2736 Using +crypto will now enable these two extensions. 2737 * New Armv8.4-A FP16 Floating Point Multiplication Variant 2738 instructions have been added. These instructions are mandatory in 2739 Armv8.4-A but available as an optional extension to Armv8.2-A and 2740 Armv8.3-A. The new extension can be used by specifying the +fp16fml 2741 architectural extension on Armv8.2-A and Armv8.3-A. On Armv8.4-A 2742 the instructions can be enabled by specifying +fp16. 2743 * New cryptographic instructions have been added as optional 2744 extensions to Armv8.2-A and newer. These instructions can be 2745 enabled with: 2746 + +sha3 New SHA3 and SHA2 instructions from Armv8.4-A. This 2747 implies +sha2. 2748 + +sm4 New SM3 and SM4 instructions from Armv8.4-A. 2749 * The Scalable Vector Extension (SVE) is now supported as an optional 2750 extension to the Armv8.2-A architecture and newer. This support 2751 includes automatic vectorization with SVE instructions, but it does 2752 not yet include the SVE Arm C Language Extensions (ACLE). It can be 2753 enabled by specifying the +sve architecture extension (for example, 2754 -march=armv8.2-a+sve). By default, the generated code works with 2755 all vector lengths, but it can be made specific to N-bit vectors 2756 using -msve-vector-bits=N. 2757 * Support has been added for the following processors (GCC 2758 identifiers in parentheses): 2759 + Arm Cortex-A75 (cortex-a75). 2760 + Arm Cortex-A55 (cortex-a55). 2761 + Arm Cortex-A55/Cortex-A75 DynamIQ big.LITTLE 2762 (cortex-a75.cortex-a55). 2763 The GCC identifiers can be used as arguments to the -mcpu or -mtune 2764 options, for example: -mcpu=cortex-a75 or -mtune=cortex-a75 or as 2765 arguments to the equivalent target attributes and pragmas. 2766 2767 ARC 2768 2769 * Added support for: 2770 + Fast interrupts. 2771 + Naked functions. 2772 + aux variable attributes. 2773 + uncached type qualifier. 2774 + Secure functions via sjli instruction. 2775 * New exception handling implementation. 2776 * Revamped trampoline implementation. 2777 * Refactored small data feature implementation, controlled via the -G 2778 command-line option. 2779 * New support for reduced register set ARC architecture 2780 configurations, controlled via the -mrf16 command-line option. 2781 * Refurbished and improved support for zero overhead loops. 2782 Introduced -mlpc-width command-line option to control the width of 2783 the lp_count register. 2784 2785 ARM 2786 2787 * The -mfpu option now takes a new option setting of -mfpu=auto. When 2788 set to this the floating-point and SIMD settings are derived from 2789 the settings of the -mcpu or -march options. The internal CPU 2790 configurations have been updated with information about the 2791 permitted floating-point configurations supported. See the user 2792 guide for further information about the extended option syntax for 2793 controlling architectural extensions via the -march option. 2794 -mfpu=auto is now the default setting unless the compiler has been 2795 configured with an explicit --with-fpu option. 2796 * The -march and -mcpu options now accept optional extensions to the 2797 architecture or CPU option, allowing the user to enable or disable 2798 any such extensions supported by that architecture or CPU such as 2799 (but not limited to) floating-point and AdvancedSIMD. For example: 2800 the option -mcpu=cortex-a53+nofp will generate code for the 2801 Cortex-A53 processor with no floating-point support. This, in 2802 combination with the new -mfpu=auto option, provides a 2803 straightforward way of specifying a valid build target through a 2804 single -mcpu or -march option. The -mtune option accepts the same 2805 arguments as -mcpu but only the CPU name has an effect on tuning. 2806 The architecture extensions do not have any effect. For details of 2807 what extensions a particular architecture or CPU option supports 2808 please refer to the [23]documentation. 2809 * The -mstructure-size-boundary option has been deprecated and will 2810 be removed in a future release. 2811 * The default link behavior for Armv6 and Armv7-R targets has been 2812 changed to produce BE8 format when generating big-endian images. A 2813 new flag -mbe32 can be used to force the linker to produce legacy 2814 BE32 format images. There is no change of behavior for Armv6-M and 2815 other Armv7 or later targets: these already defaulted to BE8 2816 format. This change brings GCC into alignment with other compilers 2817 for the ARM architecture. 2818 * The Armv8-R architecture is now supported. It can be used by 2819 specifying the -march=armv8-r option. 2820 * The Armv8.3-A architecture is now supported. It can be used by 2821 specifying the -march=armv8.3-a option. 2822 * The Armv8.4-A architecture is now supported. It can be used by 2823 specifying the -march=armv8.4-a option. 2824 * The Dot Product instructions are now supported as an optional 2825 extension to the Armv8.2-A architecture and newer and are mandatory 2826 on Armv8.4-A. The extension can be used by specifying the +dotprod 2827 architecture extension. E.g. -march=armv8.2-a+dotprod. 2828 * Support for setting extensions and architectures using the GCC 2829 target pragma and attribute has been added. It can be used by 2830 specifying #pragma GCC target ("arch=..."), #pragma GCC target 2831 ("+extension"), __attribute__((target("arch=..."))) or 2832 __attribute__((target("+extension"))). 2833 * New Armv8.4-A FP16 Floating Point Multiplication Variant 2834 instructions have been added. These instructions are mandatory in 2835 Armv8.4-A but available as an optional extension to Armv8.2-A and 2836 Armv8.3-A. The new extension can be used by specifying the +fp16fml 2837 architectural extension on Armv8.2-A and Armv8.3-A. On Armv8.4-A 2838 the instructions can be enabled by specifying +fp16. 2839 * Support has been added for the following processors (GCC 2840 identifiers in parentheses): 2841 + Arm Cortex-A75 (cortex-a75). 2842 + Arm Cortex-A55 (cortex-a55). 2843 + Arm Cortex-A55/Cortex-A75 DynamIQ big.LITTLE 2844 (cortex-a75.cortex-a55). 2845 + Arm Cortex-R52 for Armv8-R (cortex-r52). 2846 The GCC identifiers can be used as arguments to the -mcpu or -mtune 2847 options, for example: -mcpu=cortex-a75 or -mtune=cortex-r52 or as 2848 arguments to the equivalent target attributes and pragmas. 2849 2850 AVR 2851 2852 * The AVR port now supports the following XMEGA-like devices: 2853 2854 ATtiny212, ATtiny214, ATtiny412, ATtiny414, ATtiny416, ATtiny417, 2855 ATtiny814, ATtiny816, ATtiny817, ATtiny1614, ATtiny1616, ATtiny1617, 2856 ATtiny3214, ATtiny3216, ATtiny3217 2857 The new devices are listed under [24]-mmcu=avrxmega3. 2858 + These devices see flash memory in the RAM address space, so 2859 that features like PROGMEM and __flash are not needed any more 2860 (as opposed to other AVR families for which read-only data 2861 will be located in RAM except special, non-standard features 2862 are used to locate and access such data). This requires that 2863 the compiler is used with Binutils 2.29 or newer so that 2864 [25]read-only data will be located in flash memory. 2865 + A new command-line option -mshort-calls is supported. This 2866 option is used internally for multilib selection of the 2867 avrxmega3 variants. It is not an optimization option. Do not 2868 set it by hand. 2869 * The compiler now generates [26]efficient interrupt service routine 2870 (ISR) prologues and epilogues. This is achieved by using the new 2871 [27]AVR pseudo instruction __gcc_isr which is supported and 2872 resolved by the GNU assembler. 2873 + As the __gcc_isr pseudo-instruction will be resolved by the 2874 assembler, inline assembly is transparent to the process. This 2875 means that when inline assembly uses an instruction like INC 2876 that clobbers the condition code, then the assembler will 2877 detect this and generate an appropriate ISR prologue / 2878 epilogue chunk to save / restore SREG as needed. 2879 + A new command-line option -mno-gas-isr-prologues disables the 2880 generation of the __gcc_isr pseudo instruction. Any non-naked 2881 ISR will save and restore SREG, tmp_reg and zero_reg, no 2882 matter whether the respective register is clobbered or used. 2883 + The feature is turned on per default for all optimization 2884 levels except for -O0 and -Og. It is explicitly enabled by 2885 means of option -mgas-isr-prologues. 2886 + Support has been added for a new [28]AVR function attribute 2887 no_gccisr. It can be used to disable __gcc_isr pseudo 2888 instruction generation for individual ISRs. 2889 + This optimization is only available if GCC is configured with 2890 GNU Binutils 2.29 or newer; or at least with a version of 2891 Binutils that implements feature [29]PR21683. 2892 * The compiler no more saves / restores registers in main; the effect 2893 is the same as if attribute OS_task was specified for main. This 2894 optimization can be switched off by the new command-line option 2895 -mno-main-is-OS_task. 2896 2897 IA-32/x86-64 2898 2899 * The x86 port now supports the naked function attribute. 2900 * Better tuning for znver1 and Intel Core based CPUs. 2901 * Vectorization cost metrics has been reworked leading to significant 2902 improvements on some benchmarks. 2903 * GCC now supports the Intel CPU named Cannonlake through 2904 -march=cannonlake. The switch enables the AVX512VBMI, AVX512IFMA 2905 and SHA ISA extensions. 2906 * GCC now supports the Intel CPU named Icelake through 2907 -march=icelake. The switch enables the AVX512VNNI, GFNI, VAES, 2908 AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID and AVX512VPOPCNTDQ 2909 ISA extensions. 2910 * GCC now supports the Intel Control-flow Enforcement Technology 2911 (CET) extension through -fcf-protection option. 2912 2913 NDS32 2914 2915 * New command-line options -mext-perf, -mext-perf2, and -mext-string 2916 have been added for performance extension instructions. 2917 2918 Nios II 2919 2920 * The Nios II back end has been improved to generate better-optimized 2921 code. Changes include switching to LRA, more accurate cost models, 2922 and more compact code for addressing static variables. 2923 * New command-line options -mgprel-sec= and -mr0rel-sec= have been 2924 added. 2925 * The stack-smashing protection options are now enabled on Nios II. 2926 2927 PA-RISC 2928 2929 * The default call ABI on 32-bit linux has been changed from callee 2930 copies to caller copies. This affects objects larger than eight 2931 bytes passed by value. The goal is to improve compatibility with 2932 x86 and resolve issues with OpenMP. 2933 * Other PA-RISC targets are unchanged. 2934 2935 PowerPC / PowerPC64 / RS6000 2936 2937 * The PowerPC SPE support is split off to a separate powerpcspe port. 2938 The separate port is deprecated and might be removed in a future 2939 release. 2940 * The Paired Single support (as used on some PPC750 CPUs, -mpaired, 2941 powerpc*-*-linux*paired*) is deprecated and will be removed in a 2942 future release. 2943 * The Xilinx floating point support (-mxilinx-fpu, 2944 powerpc-xilinx-eabi*) is deprecated and will be removed in a future 2945 release. 2946 * Support for using big-endian AltiVec intrinsics on a little-endian 2947 target (-maltivec=be) is deprecated and will be removed in a future 2948 release. 2949 2950 Tile 2951 2952 * The TILE-Gx port is deprecated and will be removed in a future 2953 release. 2954 2955 Operating Systems 2956 2957 Windows 2958 2959 * GCC on Microsoft Windows can now be configured via 2960 --enable-mingw-wildcard or --disable-mingw-wildcard to force a 2961 specific behavior for GCC itself with regards to supporting the 2962 wildcard character. Prior versions of GCC would follow the 2963 configuration of the MinGW runtime. This behavior can still be 2964 obtained by not using the above options or by using 2965 --enable-mingw-wildcard=platform. 2966 2967 Improvements for plugin authors 2968 2969 * Plugins can now register a callback hook for when comments are 2970 encountered by the C and C++ compilers, e.g. allowing for plugins 2971 to handle documentation markup in code comments. 2972 * The gdbinit support script for debugging GCC now has a 2973 break-on-diagnostic command, providing an easy way to trigger a 2974 breakpoint whenever a diagnostic is emitted. 2975 * The API for creating fix-it hints now supports newlines, and for 2976 emitting mutually incompatible fix-it hints for one diagnostic. 2977 2978 GCC 8.1 2979 2980 This is the [30]list of problem reports (PRs) from GCC's bug tracking 2981 system that are known to be fixed in the 8.1 release. This list might 2982 not be complete (that is, it is possible that some PRs that have been 2983 fixed are not listed here). 2984 2985 GCC 8.2 2986 2987 This is the [31]list of problem reports (PRs) from GCC's bug tracking 2988 system that are known to be fixed in the 8.2 release. This list might 2989 not be complete (that is, it is possible that some PRs that have been 2990 fixed are not listed here). 2991 2992 General Improvements 2993 2994 * Fixed LTO link-time performance problems caused by an overflow in 2995 the partitioning algorithm while building large binaries. 2996 2997 Language Specific Changes 2998 2999 C++ 3000 3001 GCC 8.2 fixed a bug introduced in GCC 8.1 affecting passing or 3002 returning of classes with a deleted copy constructor and defaulted 3003 trivial move constructor (bug [32]c++/86094). GCC 8.2 introduces 3004 -fabi-version=13 and makes it the default, ABI incompatibilities 3005 between GCC 8.1 and 8.2 can be reported with -Wabi=12. See [33]C++ 3006 changes for more details. 3007 3008 Target Specific Changes 3009 3010 IA-32/x86-64 3011 3012 * -mtune=native performance regression [34]PR84413 on Intel Skylake 3013 processors has been fixed. 3014 3015 GCC 8.3 3016 3017 This is the [35]list of problem reports (PRs) from GCC's bug tracking 3018 system that are known to be fixed in the 8.3 release. This list might 3019 not be complete (that is, it is possible that some PRs that have been 3020 fixed are not listed here). 3021 3022 Windows 3023 3024 * A C++ Microsoft ABI bitfield layout bug, [36]PR87137 has been 3025 fixed. A non-field declaration could cause the current bitfield 3026 allocation unit to be completed, incorrectly placing a following 3027 bitfield into a new allocation unit. The Microsoft ABI is selected 3028 for: 3029 + Mingw targets 3030 + PowerPC, IA-32 or x86-64 targets when the -mms-bitfields 3031 option is specified, or __attribute__((ms_struct)) is used 3032 + SuperH targets when the -mhitachi option is specified, or 3033 __attribute__((renesas)) is used 3034 GCC 8 introduced additional cases of this defect, but rather than 3035 resolve only those regressions, we decided to resolve all the cases 3036 of this defect in single change. 3037 3038 GCC 8.4 3039 3040 This is the [37]list of problem reports (PRs) from GCC's bug tracking 3041 system that are known to be fixed in the 8.4 release. This list might 3042 not be complete (that is, it is possible that some PRs that have been 3043 fixed are not listed here). 3044 3045 GCC 8.5 3046 3047 This is the [38]list of problem reports (PRs) from GCC's bug tracking 3048 system that are known to be fixed in the 8.5 release. This list might 3049 not be complete (that is, it is possible that some PRs that have been 3050 fixed are not listed here). 3051 3052 Target Specific Changes 3053 3054 AArch64 3055 3056 * The option -moutline-atomics has been added to aid deployment of 3057 the Large System Extensions (LSE) on GNU/Linux systems built with a 3058 baseline architecture targeting Armv8-A. When the option is 3059 specified code is emitted to detect the presence of LSE 3060 instructions at run time and use them for standard atomic 3061 operations. For more information please refer to the documentation. 3062 3063 3064 For questions related to the use of GCC, please consult these web 3065 pages and the [39]GCC manuals. If that fails, the 3066 [40]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 3067 web pages and the development of GCC are welcome on our developer 3068 list at [41]gcc (a] gcc.gnu.org. All of [42]our lists have public 3069 archives. 3070 3071 Copyright (C) [43]Free Software Foundation, Inc. Verbatim copying and 3072 distribution of this entire article is permitted in any medium, 3073 provided this notice is preserved. 3074 3075 These pages are [44]maintained by the GCC team. Last modified 3076 2023-01-11. 3077 3078 References 3079 3080 1. http://gcc.gnu.org/gcc-8/porting_to.html 3081 2. http://gcc.gnu.org/onlinedocs/index.html#current 3082 3. https://gcc.gnu.org/ml/gcc/2018-04/msg00102.html 3083 4. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wmultistatement-macros 3084 5. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wstringop-truncation 3085 6. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82944 3086 7. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wif-not-aligned 3087 8. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Common-Variable-Attributes.html#index-warn_005fif_005fnot_005faligned-variable-attribute 3088 9. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wmissing-attributes 3089 10. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wpacked-not-aligned 3090 11. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Warray-bounds 3091 12. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wrestrict 3092 13. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wformat-overflow 3093 14. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/Warning-Options.html#index-Wformat-truncation 3094 15. https://gcc.gnu.org/PR86094 3095 16. https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Dialect-Options.html#index-Wclass-memaccess 3096 17. http://gcc.gnu.org/projects/cxx-status.html#cxx2a 3097 18. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/jit/topics/types.html#gcc_jit_type_get_vector 3098 19. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/jit/topics/expressions.html#gcc_jit_context_new_rvalue_from_vector 3099 20. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/jit/topics/types.html#gcc_jit_type_get_aligned 3100 21. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/jit/topics/function-pointers.html#gcc_jit_function_get_address 3101 22. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/jit/topics/contexts.html#gcc_jit_context_dump_reproducer_to_file 3102 23. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/ARM-Options.html#ARM-Options 3103 24. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/AVR-Options.html 3104 25. https://sourceware.org/PR21472 3105 26. https://gcc.gnu.org/PR20296 3106 27. https://sourceware.org/binutils/docs-2.29/as/AVR-Pseudo-Instructions.html 3107 28. https://gcc.gnu.org/onlinedocs/gcc-8.1.0/gcc/AVR-Function-Attributes.html 3108 29. https://sourceware.org/PR21683 3109 30. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=8.0 3110 31. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=8.2 3111 32. https://gcc.gnu.org/PR86094 3112 33. http://gcc.gnu.org/gcc-8/changes.html#cxx 3113 34. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84413 3114 35. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=8.3 3115 36. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87137 3116 37. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=8.4 3117 38. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=8.5 3118 39. https://gcc.gnu.org/onlinedocs/ 3119 40. mailto:gcc-help (a] gcc.gnu.org 3120 41. mailto:gcc (a] gcc.gnu.org 3121 42. https://gcc.gnu.org/lists.html 3122 43. https://www.fsf.org/ 3123 44. https://gcc.gnu.org/about.html 3124 ====================================================================== 3125 http://gcc.gnu.org/gcc-7/index.html 3126 3127 GCC 7 Release Series 3128 3129 (This release series is no longer supported.) 3130 3131 Nov 14, 2019 3132 3133 The [1]GNU project and the GCC developers are pleased to announce the 3134 release of GCC 7.5. 3135 3136 This release is a bug-fix release, containing fixes for regressions in 3137 GCC 7.4 relative to previous releases of GCC. 3138 3139 Release History 3140 3141 GCC 7.5 3142 Nov 14, 2019 ([2]changes, [3]documentation) 3143 3144 GCC 7.4 3145 Dec 6, 2018 ([4]changes, [5]documentation) 3146 3147 GCC 7.3 3148 Jan 25, 2018 ([6]changes, [7]documentation) 3149 3150 GCC 7.2 3151 Aug 14, 2017 ([8]changes, [9]documentation) 3152 3153 GCC 7.1 3154 May 2, 2017 ([10]changes, [11]documentation) 3155 3156 References and Acknowledgements 3157 3158 GCC used to stand for the GNU C Compiler, but since the compiler 3159 supports several other languages aside from C, it now stands for the 3160 GNU Compiler Collection. 3161 3162 A list of [12]successful builds is updated as new information becomes 3163 available. 3164 3165 The GCC developers would like to thank the numerous people that have 3166 contributed new features, improvements, bug fixes, and other changes as 3167 well as test results to GCC. This [13]amazing group of volunteers is 3168 what makes GCC successful. 3169 3170 For additional information about GCC please refer to the [14]GCC 3171 project web site or contact the [15]GCC development mailing list. 3172 3173 To obtain GCC please use [16]our mirror sites or [17]our version 3174 control system. 3175 3176 3177 For questions related to the use of GCC, please consult these web 3178 pages and the [18]GCC manuals. If that fails, the 3179 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 3180 web pages and the development of GCC are welcome on our developer 3181 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 3182 archives. 3183 3184 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 3185 distribution of this entire article is permitted in any medium, 3186 provided this notice is preserved. 3187 3188 These pages are [23]maintained by the GCC team. Last modified 3189 2022-10-26. 3190 3191 References 3192 3193 1. http://www.gnu.org/ 3194 2. http://gcc.gnu.org/gcc-7/changes.html 3195 3. http://gcc.gnu.org/onlinedocs/7.5.0/ 3196 4. http://gcc.gnu.org/gcc-7/changes.html 3197 5. http://gcc.gnu.org/onlinedocs/7.4.0/ 3198 6. http://gcc.gnu.org/gcc-7/changes.html 3199 7. http://gcc.gnu.org/onlinedocs/7.3.0/ 3200 8. http://gcc.gnu.org/gcc-7/changes.html 3201 9. http://gcc.gnu.org/onlinedocs/7.2.0/ 3202 10. http://gcc.gnu.org/gcc-7/changes.html 3203 11. http://gcc.gnu.org/onlinedocs/7.1.0/ 3204 12. http://gcc.gnu.org/gcc-7/buildstat.html 3205 13. http://gcc.gnu.org/onlinedocs/gcc/Contributors.html 3206 14. http://gcc.gnu.org/index.html 3207 15. mailto:gcc (a] gcc.gnu.org 3208 16. http://gcc.gnu.org/mirrors.html 3209 17. http://gcc.gnu.org/git.html 3210 18. https://gcc.gnu.org/onlinedocs/ 3211 19. mailto:gcc-help (a] gcc.gnu.org 3212 20. mailto:gcc (a] gcc.gnu.org 3213 21. https://gcc.gnu.org/lists.html 3214 22. https://www.fsf.org/ 3215 23. https://gcc.gnu.org/about.html 3216 ====================================================================== 3217 http://gcc.gnu.org/gcc-7/changes.html 3218 3219 GCC 7 Release Series 3220 Changes, New Features, and Fixes 3221 3222 This page is a brief summary of some of the huge number of improvements 3223 in GCC 7. For more information, see the [1]Porting to GCC 7 page and 3224 the [2]full GCC documentation. 3225 3226 Caveats 3227 3228 * GCC now uses [3]LRA (a new local register allocator) by default for 3229 new targets. 3230 * The non-standard C++0x type traits has_trivial_default_constructor, 3231 has_trivial_copy_constructor and has_trivial_copy_assign have been 3232 removed. 3233 * The libstdc++ [4]Profile Mode has been deprecated and will be 3234 removed in a future version. 3235 * The Cilk+ extensions to the C and C++ languages have been 3236 deprecated. 3237 * On ARM targets (arm*-*-*), [5]a bug introduced in GCC 5 that 3238 affects conformance to the procedure call standard (AAPCS) has been 3239 fixed. The bug affects some C++ code where class objects are passed 3240 by value to functions and could result in incorrect or inconsistent 3241 code being generated. This is an ABI change. If the option -Wpsabi 3242 is enabled (on by default) the compiler will emit a diagnostic note 3243 for code that might be affected. 3244 3245 General Optimizer Improvements 3246 3247 * GCC 7 can determine the return value or range of return values of 3248 some calls to the sprintf family of functions and make it available 3249 to other optimization passes. Some calls to the snprintf function 3250 with a zero size argument can be folded into constants. This 3251 optimization is included in -O1 and can be selectively controlled 3252 by the -fprintf-return-value option. 3253 * A new store merging pass has been added. It merges constant stores 3254 to adjacent memory locations into fewer, wider, stores. It is 3255 enabled by the -fstore-merging option and at the -O2 optimization 3256 level or higher (and -Os). 3257 * A new code hoisting optimization has been added to the partial 3258 redundancy elimination pass. It attempts to move evaluation of 3259 expressions executed on all paths to the function exit as early as 3260 possible. This primarily helps improve code size, but can improve 3261 the speed of the generated code as well. It is enabled by the 3262 -fcode-hoisting option and at the -O2 optimization level or higher 3263 (and -Os). 3264 * A new interprocedural bitwise constant propagation optimization has 3265 been added, which propagates knowledge about which bits of 3266 variables are known to be zero (including pointer alignment 3267 information) across the call graph. It is enabled by the 3268 -fipa-bit-cp option if -fipa-cp is enabled as well, and is enabled 3269 at the -O2 optimization level and higher (and -Os). This 3270 optimization supersedes interprocedural alignment propagation of 3271 GCC 6, and therefore the option -fipa-cp-alignment is now 3272 deprecated and ignored. 3273 * A new interprocedural value range propagation optimization has been 3274 added, which propagates integral range information across the call 3275 graph when variable values can be proven to be within those ranges. 3276 It is enabled by the -fipa-vrp option and at the -O2 optimization 3277 level and higher (and -Os). 3278 * A new loop splitting optimization pass has been added. Certain 3279 loops which contain a condition that is always true on one side of 3280 the iteration space and always false on the other are split into 3281 two loops, such that each of the two new loops iterates on just one 3282 side of the iteration space and the condition does not need to be 3283 checked inside of the loop. It is enabled by the -fsplit-loops 3284 option and at the -O3 optimization level or higher. 3285 * The shrink-wrapping optimization can now separate portions of 3286 prologues and epilogues to improve performance if some of the work 3287 done traditionally by prologues and epilogues is not needed on 3288 certain paths. This is controlled by the -fshrink-wrap-separate 3289 option, enabled by default. It requires target support, which is 3290 currently only implemented in the PowerPC and AArch64 ports. 3291 * AddressSanitizer gained a new sanitization option, 3292 -fsanitize-address-use-after-scope, which enables sanitization of 3293 variables whose address is taken and used after a scope where the 3294 variable is defined: 3295 3296 int 3297 main (int argc, char **argv) 3298 { 3299 char *ptr; 3300 { 3301 char my_char; 3302 ptr = &my_char; 3303 } 3304 3305 *ptr = 123; 3306 return *ptr; 3307 } 3308 3309 ==28882==ERROR: AddressSanitizer: stack-use-after-scope on address 0x7fffb8dba99 3310 0 at pc 0x0000004006d5 bp 0x7fffb8dba960 sp 0x7fffb8dba958 3311 WRITE of size 1 at 0x7fffb8dba990 thread T0 3312 #0 0x4006d4 in main /tmp/use-after-scope-1.c:10 3313 #1 0x7f9c71943290 in __libc_start_main (/lib64/libc.so.6+0x20290) 3314 #2 0x400739 in _start (/tmp/a.out+0x400739) 3315 3316 Address 0x7fffb8dba990 is located in stack of thread T0 at offset 32 in frame 3317 #0 0x40067f in main /tmp/use-after-scope-1.c:3 3318 3319 This frame has 1 object(s): 3320 [32, 33) 'my_char' <== Memory access at offset 32 is inside this variable 3321 3322 The option is enabled by default with -fsanitize=address and 3323 disabled by default with -fsanitize=kernel-address. Compared to the 3324 LLVM compiler, where the option already exists, the implementation 3325 in the GCC compiler has some improvements and advantages: 3326 + Complex uses of gotos and case labels are properly handled and 3327 should not report any false positive or false negatives. 3328 + C++ temporaries are sanitized. 3329 + Sanitization can handle invalid memory stores that are 3330 optimized out by the LLVM compiler when optimization is 3331 enabled. 3332 * The -fsanitize=signed-integer-overflow suboption of the 3333 UndefinedBehavior Sanitizer now diagnoses arithmetic overflows even 3334 on arithmetic operations with generic vectors. 3335 * Version 5 of the DWARF debugging information standard is supported 3336 through the -gdwarf-5 option. The DWARF version 4 debugging 3337 information remains the default until consumers of debugging 3338 information are adjusted. 3339 3340 New Languages and Language specific improvements 3341 3342 OpenACC support in C, C++, and Fortran continues to be maintained and 3343 improved. See the [6]OpenACC and [7]Offloading wiki pages for further 3344 information. 3345 3346 Ada 3347 3348 * On mainstream native platforms, Ada programs no longer require the 3349 stack to be made executable in order to run properly. 3350 3351 BRIG (HSAIL) 3352 3353 Support for processing BRIG 1.0 files was added in this release. BRIG 3354 is a binary format for HSAIL (Heterogeneous System Architecture 3355 Intermediate Language). The BRIG front end can be used for implementing 3356 HSAIL "finalizers" (compilation of HSAIL to a native ISA) for 3357 GCC-supported targets. An implementation of an HSAIL runtime library, 3358 libhsail-rt is also included. 3359 3360 C family 3361 3362 * New command-line options have been added for the C and C++ 3363 compilers: 3364 + -Wimplicit-fallthrough warns when a switch case falls through. 3365 This warning has five different levels. The compiler is able 3366 to parse a wide range of fallthrough comments, depending on 3367 the level. It also handles control-flow statements, such as 3368 ifs. It's possible to suppress the warning by either adding a 3369 fallthrough comment, or by using a null statement: 3370 __attribute__ ((fallthrough)); (C, C++), or [[fallthrough]]; 3371 (C++17), or [[gnu::fallthrough]]; (C++11/C++14). This warning 3372 is enabled by -Wextra. 3373 + -Wpointer-compare warns when a pointer is compared with a zero 3374 character constant. Such code is now invalid in C++11 and GCC 3375 rejects it. This warning is enabled by default. 3376 + -Wduplicated-branches warns when an if-else has identical 3377 branches. 3378 + -Wrestrict warns when an argument passed to a 3379 restrict-qualified parameter aliases with another argument. 3380 + -Wmemset-elt-size warns for memset calls, when the first 3381 argument references an array, and the third argument is a 3382 number equal to the number of elements of the array, but not 3383 the size of the array. This warning is enabled by -Wall. 3384 + -Wint-in-bool-context warns about suspicious uses of integer 3385 values where boolean values are expected. This warning is 3386 enabled by -Wall. 3387 + -Wswitch-unreachable warns when a switch statement has 3388 statements between the controlling expression and the first 3389 case label which will never be executed. This warning is 3390 enabled by default. 3391 + -Wexpansion-to-defined warns when defined is used outside #if. 3392 This warning is enabled by -Wextra or -Wpedantic. 3393 + -Wregister warns about uses of the register storage specifier. 3394 In C++17 this keyword has been removed and for C++17 this is a 3395 pedantic warning enabled by default. The warning is not 3396 emitted for the GNU Explicit Register Variables extension. 3397 + -Wvla-larger-than=N warns about unbounded uses of 3398 variable-length arrays, and about bounded uses of 3399 variable-length arrays whose bound can be larger than N bytes. 3400 + -Wduplicate-decl-specifier warns when a declaration has 3401 duplicate const, volatile, restrict or _Atomic specifier. This 3402 warning is enabled by -Wall. 3403 * GCC 6's C and C++ front ends were able to offer suggestions for 3404 misspelled field names: 3405 3406 spellcheck-fields.cc:52:13: error: 'struct s' has no member named 'colour'; did 3407 you mean 'color'? 3408 return ptr->colour; 3409 ^~~~~~ 3410 3411 GCC 7 greatly expands the scope of these suggestions. Firstly, it 3412 adds fix-it hints to such suggestions: 3413 3414 spellcheck-fields.cc:52:13: error: 'struct s' has no member named 'colour'; did 3415 you mean 'color'? 3416 return ptr->colour; 3417 ^~~~~~ 3418 color 3419 3420 The suggestions now cover many other things, such as misspelled 3421 function names: 3422 3423 spellcheck-identifiers.c:11:3: warning: implicit declaration of function 'gtk_wi 3424 dget_showall'; did you mean 'gtk_widget_show_all'? [-Wimplicit-function-declarat 3425 ion] 3426 gtk_widget_showall (w); 3427 ^~~~~~~~~~~~~~~~~~ 3428 gtk_widget_show_all 3429 3430 misspelled macro names and enum values: 3431 3432 spellcheck-identifiers.cc:85:11: error: 'MAX_ITEM' undeclared here (not in a fun 3433 ction); did you mean 'MAX_ITEMS'? 3434 int array[MAX_ITEM]; 3435 ^~~~~~~~ 3436 MAX_ITEMS 3437 3438 misspelled type names: 3439 3440 spellcheck-typenames.c:7:14: error: unknown type name 'singed'; did you mean 'si 3441 gned'? 3442 void test (singed char e); 3443 ^~~~~~ 3444 signed 3445 3446 and, in the C front end, named initializers: 3447 3448 test.c:7:20: error: 'struct s' has no member named 'colour'; did you mean 'color 3449 '? 3450 struct s test = { .colour = 3 }; 3451 ^~~~~~ 3452 color 3453 3454 * The preprocessor can now offer suggestions for misspelled 3455 directives, e.g.: 3456 3457 test.c:5:2: error:invalid preprocessing directive #endfi; did you mean #endif? 3458 #endfi 3459 ^~~~~ 3460 endif 3461 3462 * Warnings about format strings now underline the pertinent part of 3463 the string, and can offer suggested fixes. In some cases, the 3464 pertinent argument is underlined. 3465 3466 test.c:51:29: warning: format '%s' expects argument of type 'char *', but argume 3467 nt 3 has type 'int' [-Wformat=] 3468 printf ("foo: %d bar: %s baz: %d", 100, i + j, 102); 3469 ~^ ~~~~~ 3470 %d 3471 3472 * The new -Wdangling-else command-line option has been split out of 3473 -Wparentheses and warns about dangling else. 3474 * The -Wshadow warning has been split into three variants. 3475 -Wshadow=global warns for any shadowing. This is the default when 3476 using -Wshadow without any argument. -Wshadow=local only warns for 3477 a local variable shadowing another local variable or parameter. 3478 -Wshadow=compatible-local only warns for a local variable shadowing 3479 another local variable or parameter whose type is compatible (in 3480 C++ compatible means that the type of the shadowing variable can be 3481 converted to that of the shadowed variable). 3482 The following example shows the different kinds of shadow warnings: 3483 3484 enum operation { add, count }; 3485 struct container { int nr; }; 3486 3487 int 3488 container_count (struct container c, int count) 3489 { 3490 int r = 0; 3491 for (int count = 0; count > 0; count--) 3492 { 3493 struct container count = c; 3494 r += count.nr; 3495 } 3496 return r; 3497 } 3498 3499 -Wshadow=compatible-local will warn for the parameter being 3500 shadowed with the same type: 3501 3502 warn-test.c:8:12: warning: declaration of 'count' shadows a parameter [-Wshadow= 3503 compatible-local] 3504 for (int count = 0; count > 0; count--) 3505 ^~~~~ 3506 warn-test.c:5:42: note: shadowed declaration is here 3507 container_count (struct container c, int count) 3508 ^~~~~ 3509 3510 -Wshadow=local will warn for the above and for the shadowed 3511 declaration with incompatible type: 3512 3513 warn-test.c:10:24: warning: declaration of 'count' shadows a previous local [-Ws 3514 hadow=local] 3515 struct container count = c; 3516 ^~~~~ 3517 warn-test.c:8:12: note: shadowed declaration is here 3518 for (int count = 0; count > 0; count--) 3519 ^~~~~ 3520 3521 -Wshadow=global will warn for all of the above and the shadowing of 3522 the global declaration: 3523 3524 warn-test.c:5:42: warning: declaration of 'count' shadows a global declaration [ 3525 -Wshadow] 3526 container_count (struct container c, int count) 3527 ^~~~~ 3528 warn-test.c:1:23: note: shadowed declaration is here 3529 enum operation { add, count }; 3530 ^~~~~ 3531 3532 * GCC 7 contains a number of enhancements that help detect buffer 3533 overflow and other forms of invalid memory accesses. 3534 + The -Walloc-size-larger-than=size option detects calls to 3535 standard and user-defined memory allocation functions 3536 decorated with attribute alloc_size whose argument exceeds the 3537 specified size (PTRDIFF_MAX by default). The option also 3538 detects arithmetic overflow in the computation of the size in 3539 two-argument allocation functions like calloc where the total 3540 size is the product of the two arguments. Since calls with an 3541 excessive size cannot succeed they are typically the result of 3542 programming errors. Such bugs have been known to be the source 3543 of security vulnerabilities and a target of exploits. 3544 -Walloc-size-larger-than=PTRDIFF_MAX is included in -Wall. 3545 For example, the following call to malloc incorrectly tries to 3546 avoid passing a negative argument to the function and instead 3547 ends up unconditionally invoking it with an argument less than 3548 or equal to zero. Since after conversion to the type of the 3549 argument of the function (size_t) a negative argument results 3550 in a value in excess of the maximum PTRDIFF_MAX the call is 3551 diagnosed. 3552 3553 void* f (int n) 3554 { 3555 return malloc (n > 0 ? 0 : n); 3556 } 3557 3558 warning: argument 1 range [2147483648, 4294967295] exceeds maximum object size 2 3559 147483647 [-Walloc-size-larger-than=] 3560 3561 + The -Walloc-zero option detects calls to standard and 3562 user-defined memory allocation functions decorated with 3563 attribute alloc_size with a zero argument. -Walloc-zero is not 3564 included in either -Wall or -Wextra and must be explicitly 3565 enabled. 3566 + The -Walloca option detects all calls to the alloca function 3567 in the program. -Walloca is not included in either -Wall or 3568 -Wextra and must be explicitly enabled. 3569 + The -Walloca-larger-than=size option detects calls to the 3570 alloca function whose argument either may exceed the specified 3571 size, or that is not known to be sufficiently constrained to 3572 avoid exceeding it. -Walloca-larger-than is not included in 3573 either -Wall or -Wextra and must be explicitly enabled. 3574 For example, compiling the following snippet with 3575 -Walloca-larger-than=1024 results in a warning because even 3576 though the code appears to call alloca only with sizes of 1kb 3577 and less, since n is signed, a negative value would result in 3578 a call to the function well in excess of the limit. 3579 3580 void f (int n) 3581 { 3582 char *d; 3583 if (n < 1025) 3584 d = alloca (n); 3585 else 3586 d = malloc (n); 3587 ... 3588 } 3589 3590 warning: argument to 'alloca may be too large due to conversion from 'int' to 'l 3591 ong unsigned int' [-Walloca-larger-than=] 3592 3593 In contrast, a call to alloca that isn't bounded at all such 3594 as in the following function will elicit the warning below 3595 regardless of the size argument to the option. 3596 3597 void f (size_t n) 3598 { 3599 char *d = alloca (n); 3600 ... 3601 } 3602 3603 warning: unbounded use of 'alloca' [-Walloca-larger-than=] 3604 3605 + The -Wformat-overflow=level option detects certain and likely 3606 buffer overflow in calls to the sprintf family of formatted 3607 output functions. Although the option is enabled even without 3608 optimization it works best with -O2 and higher. 3609 For example, in the following snippet the call to sprintf is 3610 diagnosed because even though its output has been constrained 3611 using the modulo operation it could result in as many as three 3612 bytes if mday were negative. The solution is to either 3613 allocate a larger buffer or make sure the argument is not 3614 negative, for example by changing mday's type to unsigned or 3615 by making the type of the second operand of the modulo 3616 expression unsigned: 100U. 3617 3618 void* f (int mday) 3619 { 3620 char *buf = malloc (3); 3621 sprintf (buf, "%02i", mday % 100); 3622 return buf; 3623 } 3624 3625 warning: 'sprintf may write a terminating nul past the end of the destination [- 3626 Wformat-overflow=] 3627 note: 'sprintf' output between 3 and 4 bytes into a destination of size 3 3628 3629 + The -Wformat-truncation=level option detects certain and 3630 likely output truncation in calls to the snprintf family of 3631 formatted output functions. -Wformat-truncation=1 is included 3632 in -Wall and enabled without optimization but works best with 3633 -O2 and higher. 3634 For example, the following function attempts to format an 3635 integer between 0 and 255 in hexadecimal, including the 0x 3636 prefix, into a buffer of four characters. But since the 3637 function must always terminate output by the null character 3638 ('\0') such a buffer is only big enough to fit just one digit 3639 plus the prefix. Therefore the snprintf call is diagnosed. To 3640 avoid the warning either use a bigger buffer or handle the 3641 function's return value which indicates whether or not its 3642 output has been truncated. 3643 3644 void f (unsigned x) 3645 { 3646 char d[4]; 3647 snprintf (d, sizeof d, "%#02x", x & 0xff); 3648 ... 3649 } 3650 3651 warning: 'snprintf' output may be truncated before the last format character [-W 3652 format-truncation=] 3653 note: 'snprintf' output between 3 and 5 bytes into a destination of size 4 3654 3655 + The -Wnonnull option has been enhanced to detect a broader set 3656 of cases of passing null pointers to functions that expect a 3657 non-null argument (those decorated with attribute nonnull). By 3658 taking advantage of optimizations the option can detect many 3659 more cases of the problem than in prior GCC versions. 3660 + The -Wstringop-overflow=type option detects buffer overflow in 3661 calls to string handling functions like memcpy and strcpy. The 3662 option relies on [8]Object Size Checking and has an effect 3663 similar to defining the _FORTIFY_SOURCE macro. 3664 -Wstringop-overflow=2 is enabled by default. 3665 For example, in the following snippet, because the call to 3666 strncat specifies a maximum that allows the function to write 3667 past the end of the destination, it is diagnosed. To correct 3668 the problem and avoid the overflow the function should be 3669 called with a size of at most sizeof d - strlen(d) - 1. 3670 3671 void f (const char *fname) 3672 { 3673 char d[8]; 3674 strncpy (d, "/tmp/", sizeof d); 3675 strncat (d, fname, sizeof d); 3676 ... 3677 } 3678 3679 warning: specified bound 8 equals the size of the destination [-Wstringop-overfl 3680 ow=] 3681 3682 * The <limits.h> header provided by GCC defines macros such as 3683 INT_WIDTH for the width in bits of integer types, if 3684 __STDC_WANT_IEC_60559_BFP_EXT__ is defined before the header is 3685 included. The <stdint.h> header defines such macros as SIZE_WIDTH 3686 and INTMAX_WIDTH for the width of some standard typedef names for 3687 integer types, again if __STDC_WANT_IEC_60559_BFP_EXT__ is defined 3688 before the header is included; note that GCC's implementation of 3689 this header is only used for freestanding compilations, not hosted 3690 compilations, on most systems. These macros come from ISO/IEC TS 3691 18661-1:2014. 3692 * The <float.h> header provided by GCC defines the macro 3693 CR_DECIMAL_DIG, from ISO/IEC TS 18661-1:2014, if 3694 __STDC_WANT_IEC_60559_BFP_EXT__ is defined before the header is 3695 included. This represents the number of decimal digits for which 3696 conversions between decimal character strings and binary formats, 3697 in both directions, are correctly rounded, and currently has the 3698 value of UINTMAX_MAX on all systems, reflecting that GCC's 3699 compile-time conversions are correctly rounded for any number of 3700 digits. 3701 * New __builtin_add_overflow_p, __builtin_sub_overflow_p, 3702 __builtin_mul_overflow_p built-in functions have been added. These 3703 work similarly to their siblings without the _p suffix, but do not 3704 actually store the result of the arithmetics anywhere, just return 3705 whether the operation would overflow. Calls to these built-ins with 3706 integer constant arguments evaluate to integer constants 3707 expressions. 3708 For example, in the following, c is assigned the result of a * b 3709 only if the multiplication does not overflow, otherwise it is 3710 assigned the value zero. The multiplication is performed at 3711 compile-time and without triggering a -Woverflow warning. 3712 3713 enum { 3714 a = 12345678, 3715 b = 87654321, 3716 c = __builtin_mul_overflow_p (a, b, a) ? 0 : a * b 3717 }; 3718 3719 C 3720 3721 * The C front end now supports type names _FloatN for floating-point 3722 types with IEEE interchange formats and _FloatNx for floating-point 3723 types with IEEE extended formats. These type names come from 3724 ISO/IEC TS 18661-3:2015. 3725 The set of types supported depends on the target for which GCC is 3726 configured. Most targets support _Float32, _Float32x and _Float64. 3727 _Float128 is supported on targets where IEEE binary128 encoding was 3728 already supported as long double or __float128. _Float64x is 3729 supported on targets where a type with either binary128 or Intel 3730 extended precision format is available. 3731 Constants with these types are supported using suffixes fN, FN, fNx 3732 and FNx (e.g., 1.2f128 or 2.3F64x). Macros such as FLT128_MAX are 3733 defined in <float.h> if __STDC_WANT_IEC_60559_TYPES_EXT__ is 3734 defined before it is included. 3735 These new types are always distinct from each other and from float, 3736 double and long double, even if they have the same encoding. 3737 Complex types such as _Complex _Float128 are also supported. 3738 Type-generic built-in functions such as __builtin_isinf support the 3739 new types, and the following type-specific built-in functions have 3740 versions (suffixed fN or fNx) for the new types: 3741 __builtin_copysign, __builtin_fabs, __builtin_huge_val, 3742 __builtin_inf, __builtin_nan, __builtin_nans. 3743 * Compilation with -fopenmp is now compatible with the C11 _Atomic 3744 keyword. 3745 3746 C++ 3747 3748 * The C++ front end has experimental support for all of the current 3749 C++17 draft with the -std=c++1z or -std=gnu++1z flags, including if 3750 constexpr, class template argument deduction, auto template 3751 parameters, and structured bindings. For a full list of new 3752 features, see [9]the C++ status page. 3753 * C++17 support for new of over-aligned types can be enabled in other 3754 modes with the -faligned-new flag. 3755 * The C++17 evaluation order requirements can be selected in other 3756 modes with the -fstrong-eval-order flag, or disabled in C++17 mode 3757 with -fno-strong-eval-order. 3758 * The default semantics of inherited constructors has changed in all 3759 modes, following [10]P0136. Essentially, overload resolution 3760 happens as if calling the inherited constructor directly, and the 3761 compiler fills in construction of the other bases and members as 3762 needed. Most uses should not need any changes. The old behavior can 3763 be restored with -fno-new-inheriting-ctors, or -fabi-version less 3764 than 11. 3765 * The resolution of DR 150 on matching of template template 3766 parameters, allowing default template arguments to make a template 3767 match a parameter, is currently enabled by default in C++17 mode 3768 only. The default can be overridden with -f{no-,}new-ttp-matching. 3769 * The C++ front end will now provide fix-it hints for some missing 3770 semicolons, allowing for automatic fixes by IDEs: 3771 3772 test.cc:4:11: error: expected ';' after class definition 3773 class a {} 3774 ^ 3775 ; 3776 3777 * -Waligned-new has been added to the C++ front end. It warns about 3778 new of type with extended alignment without -faligned-new. 3779 3780 Runtime Library (libstdc++) 3781 3782 * The type of exception thrown by iostreams, std::ios_base::failure, 3783 now uses the [11]cxx11 ABI. 3784 * Experimental support for C++17, including the following new 3785 features: 3786 + std::string_view; 3787 + std::any, std::optional, and std::variant; 3788 + std::invoke, std::is_invocable, std::is_nothrow_invocable, and 3789 invoke_result; 3790 + std::is_swappable, and std::is_nothrow_swappable; 3791 + std::apply, and std::make_from_tuple; 3792 + std::void_t, std::bool_constant, std::conjunction, 3793 std::disjunction, and std::negation; 3794 + Variable templates for type traits; 3795 + Mathematical Special Functions; 3796 + std::chrono::floor, std::chrono::ceil, std::chrono::round, and 3797 std::chrono::abs; 3798 + std::clamp, std::gcd, std::lcm, 3-dimensional std::hypot; 3799 + std::scoped_lock, std::shared_mutex, 3800 std::atomic<T>::is_always_lock_free; 3801 + std::sample, std::default_searcher, std::boyer_moore_searcher 3802 and std::boyer_moore_horspool_searcher; 3803 + Extraction and re-insertion of map and set nodes, try_emplace 3804 members for maps, and functions for accessing containers 3805 std::size, std::empty, and std::data; 3806 + std::shared_ptr support for arrays, 3807 std::shared_ptr<T>::weak_type, 3808 std::enable_shared_from_this<T>::weak_from_this(), and 3809 std::owner_less<void>; 3810 + std::byte; 3811 + std::as_const, std::not_fn, 3812 std::has_unique_object_representations, constexpr 3813 std::addressof. 3814 Thanks to Daniel Krgler, Tim Shen, Edward Smith-Rowland, and Ville 3815 Voutilainen for work on the C++17 support. 3816 * A new power-of-two rehashing policy for use with the _Hashtable 3817 internals, thanks to Franois Dumont. 3818 3819 Fortran 3820 3821 * Support for a number of extensions for compatibility with legacy 3822 code with new flags: 3823 + -fdec-structure Support for DEC STRUCTURE and UNION 3824 + -fdec-intrinsic-ints Support for new integer intrinsics with 3825 B/I/J/K prefixes such as BABS, JIAND... 3826 + -fdec-math Support for additional math intrinsics, including 3827 COTAN and degree-valued trigonometric functions such as TAND, 3828 ASIND... 3829 + -fdec Enable the -fdec-* family of extensions. 3830 * New flag -finit-derived to allow default initialization of 3831 derived-type variables. 3832 * Improved DO loops with step equal to 1 or -1, generates faster code 3833 without a loop preheader. A new warning, -Wundefined-do-loop, warns 3834 when a loop iterates either to HUGE(i) (with step equal to 1), or 3835 to -HUGE(i) (with step equal to -1). Invalid behavior can be caught 3836 at run time with -fcheck=do enabled: 3837 3838 program test 3839 implicit none 3840 integer(1) :: i 3841 do i = -HUGE(i)+10, -HUGE(i)-1, -1 3842 print *, i 3843 end do 3844 end program test 3845 3846 At line 8 of file do_check_12.f90 3847 Fortran runtime error: Loop iterates infinitely 3848 3849 * Version 4.5 of the [12]OpenMP specification is now partially 3850 supported in the Fortran compiler; the largest missing item is 3851 structure element mapping. 3852 * User-defined derived-type input/output (UDTIO) is added. 3853 * Derived type coarrays with allocatable and pointer components are 3854 partially supported. 3855 * Non-constant stop codes and error stop codes (Fortran 2015 3856 feature). 3857 * Derived types with allocatable components of recursive type. 3858 * Intrinsic assignment to polymorphic variables. 3859 * Improved submodule support. 3860 * Improved diagnostics (polymorphic results in pure functions). 3861 * Coarray: Support for failed images (Fortan 2015 feature). 3862 3863 Go 3864 3865 * GCC 7 provides a complete implementation of the Go 1.8.1 user 3866 packages. 3867 * Compared to the Go 1.8.1 toolchain, the garbage collector is more 3868 conservative and less concurrent. 3869 * Escape analysis is available for experimental use via the 3870 -fgo-optimize-allocs option. The -fgo-debug-escape prints 3871 information useful for debugging escape analysis choices. 3872 3873 Java (GCJ) 3874 3875 The GCC Java front end and associated libjava runtime library have been 3876 removed from GCC. 3877 3878 libgccjit 3879 3880 The libgccjit API gained support for marking calls as requiring 3881 tail-call optimization via a new entry point: 3882 [13]gcc_jit_rvalue_set_bool_require_tail_call. 3883 3884 libgccjit performs numerous checks at the API boundary, but if these 3885 succeed, it previously ignored errors and other diagnostics emitted 3886 within the core of GCC, and treated the compile of a gcc_jit_context as 3887 having succeeded. As of GCC 7 it now ensures that if any diagnostics 3888 are emitted, they are visible from the libgccjit API, and that the the 3889 context is flagged as having failed. 3890 3891 New Targets and Target Specific Improvements 3892 3893 AArch64 3894 3895 * GCC has been updated to the latest revision of the procedure call 3896 standard (AAPCS64) to provide support for parameter passing when 3897 data types have been over-aligned. 3898 * The ARMv8.3-A architecture is now supported. It can be used by 3899 specifying the -march=armv8.3-a option. 3900 * The option -msign-return-address= is supported to enable return 3901 address protection using ARMv8.3-A Pointer Authentication 3902 Extensions. For more information on the arguments accepted by this 3903 option, please refer to [14]AArch64-Options. 3904 * The ARMv8.2-A architecture and the ARMv8.2-A 16-bit Floating-Point 3905 Extensions are now supported. They can be used by specifying the 3906 -march=armv8.2-a or -march=armv8.2-a+fp16 options. The 16-bit 3907 Floating-Point Extensions introduce new half-precision data 3908 processing floating-point instructions. 3909 * Support has been added for the following processors (GCC 3910 identifiers in parentheses): ARM Cortex-A73 (cortex-a73), Broadcom 3911 Vulcan (vulcan), Cavium ThunderX CN81xx (thunderxt81), Cavium 3912 ThunderX CN83xx (thunderxt83), Cavium ThunderX CN88xx 3913 (thunderxt88), Cavium ThunderX CN88xx pass 1.x (thunderxt88p1), 3914 Cavium ThunderX 2 CN99xx (thunderx2t99), Qualcomm Falkor (falkor). 3915 The GCC identifiers can be used as arguments to the -mcpu or -mtune 3916 options, for example: -mcpu=cortex-a73 or -mtune=vulcan or as 3917 arguments to the equivalent target attributes and pragmas. 3918 3919 ARC 3920 3921 * Added support for ARC HS and ARC EM processors. 3922 * Added support for ARC EM variation found in Intel QuarkSE SoCs. 3923 * Added support for NPS400 ARC700 based CPUs. 3924 * Thread Local Storage is now supported by ARC CPUs. 3925 * Fixed errors for ARC600 when using 32x16 multiplier option. 3926 * Fixed PIE for ARC CPUs. 3927 * New CPU templates are supported via multilib. 3928 3929 ARM 3930 3931 * Support for the ARMv5 and ARMv5E architectures has been deprecated 3932 (which have no known implementations) and will be removed in a 3933 future GCC release. Note that ARMv5T, ARMv5TE and ARMv5TEJ 3934 architectures remain supported. The values armv5 and armv5e of 3935 -march are thus deprecated. 3936 * The ARMv8.2-A architecture and the ARMv8.2-A 16-bit Floating-Point 3937 Extensions are now supported. They can be used by specifying the 3938 -march=armv8.2-a or -march=armv8.2-a+fp16 options. The 16-bit 3939 Floating-Point Extensions introduce new half-precision data 3940 processing floating-point instructions. 3941 * The ARMv8-M architecture is now supported in its two architecture 3942 profiles: ARMv8-M Baseline and ARMv8-M Mainline with its DSP and 3943 Floating-Point Extensions. They can be used by specifying the 3944 -march=armv8-m.base, armv8-m.main or armv8-m.main+dsp options. 3945 * Support has been added for the following processors (GCC 3946 identifiers in parentheses): ARM Cortex-A73 (cortex-a73), ARM 3947 Cortex-M23 (cortex-m23) and ARM Cortex-M33 (cortex-m33). The GCC 3948 identifiers can be used as arguments to the -mcpu or -mtune 3949 options, for example: -mcpu=cortex-a73 or -mtune=cortex-m33. 3950 * A new command-line option -mpure-code has been added. It does not 3951 allow constant data to be placed in code sections. This option is 3952 only available when generating non-PIC code for ARMv7-M targets. 3953 * Support for the ACLE Coprocessor Intrinsics has been added. This 3954 enables the generation of coprocessor instructions through the use 3955 of intrinsics such as cdp, ldc, and others. 3956 * The configure option --with-multilib-list now accepts the value 3957 rmprofile to build multilib libraries for a range of embedded 3958 targets. See our [15]installation instructions for details. 3959 3960 AVR 3961 3962 * On the reduced Tiny cores, the progmem [16]variable attribute is 3963 now properly supported. Respective read-only variables are located 3964 in flash memory in section .progmem.data. No special code is needed 3965 to access such variables; the compiler automatically adds an offset 3966 of 0x4000 to all addresses, which is needed to access variables in 3967 flash memory. As opposed to ordinary cores where it is sufficient 3968 to specify the progmem attribute with definitions, on the reduced 3969 Tiny cores the attribute also has to be specified with (external) 3970 declarations: 3971 3972 extern const int array[] __attribute__((__progmem__)); 3973 3974 int get_value2 (void) 3975 { 3976 /* Access via addresses array + 0x4004 and array + 0x4005. */ 3977 return array[2]; 3978 } 3979 3980 const int* get_address (unsigned idx) 3981 { 3982 /* Returns array + 0x4000 + 2 * idx. */ 3983 return &array[idx]; 3984 } 3985 3986 * A new command-line option -Wmisspelled-isr has been added. It turns 3987 off -- or turns into errors -- warnings that are reported for 3988 interrupt service routines (ISRs) which don't follow AVR-LibC's 3989 naming convention of prefixing ISR names with __vector. 3990 * __builtin_avr_nops(n) is a new [17]built-in function that inserts n 3991 NOP instructions into the instruction stream. n must be a value 3992 known at compile time. 3993 3994 IA-32/x86-64 3995 3996 * Support for the AVX-512 Fused Multiply Accumulation Packed Single 3997 precision (4FMAPS), AVX-512 Vector Neural Network Instructions Word 3998 variable precision (4VNNIW), AVX-512 Vector Population Count 3999 (VPOPCNTDQ) and Software Guard Extensions (SGX) ISA extensions has 4000 been added. 4001 4002 NVPTX 4003 4004 * OpenMP target regions can now be offloaded to NVidia PTX GPGPUs. 4005 See the [18]Offloading Wiki on how to configure it. 4006 4007 PowerPC / PowerPC64 / RS6000 4008 4009 * The PowerPC port now uses LRA by default. 4010 * GCC now diagnoses inline assembly that clobbers register r2. This 4011 has always been invalid code, and is no longer quietly tolerated. 4012 * The PowerPC port's support for ISA 3.0 (-mcpu=power9) has been 4013 enhanced to generate more of the new instructions by default, and 4014 to provide more built-in functions to generate code for other new 4015 instructions. 4016 * The configuration option --enable-gnu-indirect-function is now 4017 enabled by default on PowerPC GNU/Linux builds. 4018 * The PowerPC port will now allow 64-bit and 32-bit integer types to 4019 be allocated to the VSX vector registers (ISA 2.06 and above). In 4020 addition, on ISA 3.0, 16-bit and 8-bit integer types can be 4021 allocated in the vector registers. Previously, only 64-bit integer 4022 types were allowed in the traditional floating point registers. 4023 * New options -mstack-protector-guard=global, 4024 -mstack-protector-guard=tls, -mstack-protector-guard-reg=, and 4025 -mstack-protector-guard-offset= change how the stack protector gets 4026 the value to use as canary. 4027 4028 S/390, System z, IBM z Systems, IBM Z 4029 4030 * Support for the IBM z14 processor has been added. When using the 4031 -march=z14 option, the compiler will generate code making use of 4032 the new instructions introduced with the vector enhancement 4033 facility and the miscellaneous instruction extension facility 2. 4034 The -mtune=z14 option enables z14 specific instruction scheduling 4035 without making use of new instructions. 4036 * Builtins for the new vector instructions have been added and can be 4037 enabled using the -mzvector option. 4038 4039 RISC-V 4040 4041 * Support for the RISC-V instruction set has been added. 4042 4043 RX 4044 4045 Basic support for atomic built-in function has been added. It is 4046 currently implemented by flipping interrupts off and on as needed. 4047 4048 SH 4049 4050 * Support for SH5/SH64 has been removed. 4051 * Improved utilization of delay slots on SH2A. 4052 * Improved utilization of zero-displacement conditional branches. 4053 * The following deprecated options have been removed 4054 + -mcbranchdi 4055 + -mcmpeqdi 4056 + -minvalid-symbols 4057 + -msoft-atomic 4058 + -mspace 4059 + -madjust-unroll 4060 * Support for the following SH2A instructions has been added 4061 + mov.b @-Rm,R0 4062 + mov.w @-Rm,R0 4063 + mov.l @-Rm,R0 4064 + mov.b R0,@Rn+ 4065 + mov.w R0,@Rn+ 4066 + mov.l R0,@Rn+ 4067 4068 SPARC 4069 4070 * The SPARC port now uses LRA by default. 4071 * Support for the new Subtract-Extended-with-Carry instruction 4072 available in SPARC M7 (Niagara 7) has been added. 4073 4074 Operating Systems 4075 4076 AIX 4077 4078 * Visibility support has been enabled for AIX 7.1 and above. 4079 4080 Fuchsia 4081 4082 * Support has been added for the [19]Fuchsia OS. 4083 4084 RTEMS 4085 4086 * The ABI changes on ARM so that no short enums are used by default. 4087 4088 Other significant improvements 4089 4090 * -fverbose-asm previously emitted information on the meanings of 4091 assembly expressions. This has been extended so that it now also 4092 prints comments showing the source lines that correspond to the 4093 assembly, making it easier to read the generated assembly 4094 (especially with larger functions). For example, given this C 4095 source file: 4096 4097 int test (int n) 4098 { 4099 int i; 4100 int total = 0; 4101 4102 for (i = 0; i < n; i++) 4103 total += i * i; 4104 return total; 4105 } 4106 4107 -fverbose-asm now gives output similar to this for the function 4108 body (when compiling for x86_64, with -Os): 4109 4110 .text 4111 .globl test 4112 .type test, @@function 4113 test: 4114 .LFB0: 4115 .cfi_startproc 4116 # example.c:4: int total = 0; 4117 xorl %eax, %eax # <retval> 4118 # example.c:6: for (i = 0; i < n; i++) 4119 xorl %edx, %edx # i 4120 .L2: 4121 # example.c:6: for (i = 0; i < n; i++) 4122 cmpl %edi, %edx # n, i 4123 jge .L5 #, 4124 # example.c:7: total += i * i; 4125 movl %edx, %ecx # i, tmp92 4126 imull %edx, %ecx # i, tmp92 4127 # example.c:6: for (i = 0; i < n; i++) 4128 incl %edx # i 4129 # example.c:7: total += i * i; 4130 addl %ecx, %eax # tmp92, <retval> 4131 jmp .L2 # 4132 .L5: 4133 # example.c:10: } 4134 ret 4135 .cfi_endproc 4136 4137 * Two new options have been added for printing fix-it hints: 4138 + -fdiagnostics-parseable-fixits allows for fix-it hints to be 4139 emitted in a machine-readable form, suitable for consumption 4140 by IDEs. For example, given: 4141 4142 spellcheck-fields.cc:52:13: error: 'struct s' has no member named 'colour'; did 4143 you mean 'color'? 4144 return ptr->colour; 4145 ^~~~~~ 4146 color 4147 4148 it will emit: 4149 4150 fix-it:"spellcheck-fields.cc":{52:13-52:19}:"color" 4151 4152 + -fdiagnostics-generate-patch will print a patch in "unified" 4153 format after any diagnostics are printed, showing the result 4154 of applying all fix-it hints. For the above example it would 4155 emit: 4156 4157 --- spellcheck-fields.cc 4158 +++ spellcheck-fields.cc 4159 @@ -49,5 +49,5 @@ 4160 4161 color get_color(struct s *ptr) 4162 { 4163 - return ptr->colour; 4164 + return ptr->color; 4165 } 4166 4167 * The gcc and g++ driver programs will now provide suggestions for 4168 misspelled arguments to command-line options. 4169 4170 $ gcc -c test.c -ftls-model=global-dinamic 4171 gcc: error: unknown TLS model 'global-dinamic' 4172 gcc: note: valid arguments to '-ftls-model=' are: global-dynamic initial-exec lo 4173 cal-dynamic local-exec; did you mean 'global-dynamic'? 4174 4175 * The compiler will now provide suggestions for misspelled 4176 parameters. 4177 4178 $ gcc -c test.c --param max-early-inliner-iteration=3 4179 cc1: error: invalid --param name 'max-early-inliner-iteration'; did you mean 'ma 4180 x-early-inliner-iterations'? 4181 4182 * Profile-guided optimization (PGO) instrumentation, as well as test 4183 coverage (GCOV), can newly instrument constructors (functions marks 4184 with __attribute__((constructor))), destructors and C++ 4185 constructors (and destructors) of classes that are used as the type 4186 of a global variable. 4187 * A new option -fprofile-update=atomic prevents creation of corrupted 4188 profiles created during an instrumentation run (-fprofile=generate) 4189 of an application. The downside of the option is a speed penalty. 4190 Providing -pthread on the command line selects atomic profile 4191 updating (when supported by the target). 4192 * GCC's already extensive testsuite has gained some new capabilities, 4193 to further improve the reliability of the compiler: 4194 + GCC now has an internal unit-testing API and a suite of tests 4195 for programmatic self-testing of subsystems. 4196 + GCC's C front end has been extended so that it can parse dumps 4197 of GCC's internal representations, allowing for DejaGnu tests 4198 that more directly exercise specific optimization passes. This 4199 covers both the [20]GIMPLE representation (for testing 4200 higher-level optimizations) and the [21]RTL representation, 4201 allowing for more direct testing of lower-level details, such 4202 as register allocation and instruction selection. 4203 4204 GCC 7.1 4205 4206 This is the [22]list of problem reports (PRs) from GCC's bug tracking 4207 system that are known to be fixed in the 7.1 release. This list might 4208 not be complete (that is, it is possible that some PRs that have been 4209 fixed are not listed here). 4210 4211 GCC 7.2 4212 4213 This is the [23]list of problem reports (PRs) from GCC's bug tracking 4214 system that are known to be fixed in the 7.2 release. This list might 4215 not be complete (that is, it is possible that some PRs that have been 4216 fixed are not listed here). 4217 4218 Target Specific Changes 4219 4220 SPARC 4221 4222 * Support for the SPARC M8 processor has been added. 4223 * The switches -mfix-ut700 and -mfix-gr712rc have been added to work 4224 around an erratum in LEON3FT processors. 4225 * Use of the Floating-point Multiply Single to Double (FsMULd) 4226 instruction can now be controlled by the -mfsmuld and -fno-fsmuld 4227 options. 4228 4229 Operating Systems 4230 4231 RTEMS 4232 4233 * The Ada run-time support uses now thread-local storage (TLS). 4234 * Support for RISC-V has been added. 4235 * Support for 64-bit PowerPC using the ELFv2 ABI with 64-bit long 4236 double has been added. 4237 4238 GCC 7.3 4239 4240 This is the [24]list of problem reports (PRs) from GCC's bug tracking 4241 system that are known to be fixed in the 7.3 release. This list might 4242 not be complete (that is, it is possible that some PRs that have been 4243 fixed are not listed here). 4244 4245 Target Specific Changes 4246 4247 SPARC 4248 4249 * Workarounds for the four [25]LEON3FT errata GRLIB-TN-0010..0013 4250 have been added. Relevant errata are activated by the target 4251 specific -mfix-ut699, -mfix-ut700 and -mfix-gr712rc switches. 4252 4253 Operating Systems 4254 4255 RTEMS 4256 4257 * Support has been added for Epiphany target. 4258 4259 GCC 7.4 4260 4261 This is the [26]list of problem reports (PRs) from GCC's bug tracking 4262 system that are known to be fixed in the 7.4 release. This list might 4263 not be complete (that is, it is possible that some PRs that have been 4264 fixed are not listed here). 4265 4266 GCC 7.5 4267 4268 This is the [27]list of problem reports (PRs) from GCC's bug tracking 4269 system that are known to be fixed in the 7.5 release. This list might 4270 not be complete (that is, it is possible that some PRs that have been 4271 fixed are not listed here). 4272 4273 4274 For questions related to the use of GCC, please consult these web 4275 pages and the [28]GCC manuals. If that fails, the 4276 [29]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 4277 web pages and the development of GCC are welcome on our developer 4278 list at [30]gcc (a] gcc.gnu.org. All of [31]our lists have public 4279 archives. 4280 4281 Copyright (C) [32]Free Software Foundation, Inc. Verbatim copying and 4282 distribution of this entire article is permitted in any medium, 4283 provided this notice is preserved. 4284 4285 These pages are [33]maintained by the GCC team. Last modified 4286 2022-10-26. 4287 4288 References 4289 4290 1. http://gcc.gnu.org/gcc-7/porting_to.html 4291 2. http://gcc.gnu.org/onlinedocs/index.html#current 4292 3. https://gcc.gnu.org/wiki/LRAIsDefault 4293 4. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/libstdc++/manual/manual/profile_mode.html 4294 5. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77728 4295 6. https://gcc.gnu.org/wiki/OpenACC 4296 7. https://gcc.gnu.org/wiki/Offloading 4297 8. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gcc/Object-Size-Checking.html 4298 9. https://gcc.gnu.org/projects/cxx-status.html#cxx1z 4299 10. https://wg21.link/p0136 4300 11. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/libstdc++/manual/using_dual_abi.html 4301 12. https://www.openmp.org/specifications/ 4302 13. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/jit/topics/expressions.html#gcc_jit_rvalue_set_bool_require_tail_call 4303 14. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gcc/AArch64-Options.html#AArch64-Options 4304 15. https://gcc.gnu.org/install/configure.html 4305 16. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gcc/AVR-Variable-Attributes.html 4306 17. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gcc/AVR-Built-in-Functions.html 4307 18. https://gcc.gnu.org/wiki/Offloading 4308 19. https://fuchsia.googlesource.com/ 4309 20. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gccint/GIMPLE-Tests.html 4310 21. https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gccint/RTL-Tests.html 4311 22. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=7.0 4312 23. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=7.2 4313 24. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=7.3 4314 25. https://www.gaisler.com/index.php/information/app-tech-notes 4315 26. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=7.4 4316 27. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=7.5 4317 28. https://gcc.gnu.org/onlinedocs/ 4318 29. mailto:gcc-help (a] gcc.gnu.org 4319 30. mailto:gcc (a] gcc.gnu.org 4320 31. https://gcc.gnu.org/lists.html 4321 32. https://www.fsf.org/ 4322 33. https://gcc.gnu.org/about.html 4323 ====================================================================== 4324 http://gcc.gnu.org/gcc-6/index.html 4325 4326 GCC 6 Release Series 4327 4328 (This release series is no longer supported.) 4329 4330 October 26, 2018 4331 4332 The [1]GNU project and the GCC developers are pleased to announce the 4333 release of GCC 6.5. 4334 4335 This release is a bug-fix release, containing fixes for regressions in 4336 GCC 6.4 relative to previous releases of GCC. 4337 4338 Release History 4339 4340 GCC 6.5 4341 October 26, 2018 ([2]changes, [3]documentation) 4342 4343 GCC 6.4 4344 July 4, 2017 ([4]changes, [5]documentation) 4345 4346 GCC 6.3 4347 December 21, 2016 ([6]changes, [7]documentation) 4348 4349 GCC 6.2 4350 August 22, 2016 ([8]changes, [9]documentation) 4351 4352 GCC 6.1 4353 April 27, 2016 ([10]changes, [11]documentation) 4354 4355 References and Acknowledgements 4356 4357 GCC used to stand for the GNU C Compiler, but since the compiler 4358 supports several other languages aside from C, it now stands for the 4359 GNU Compiler Collection. 4360 4361 A list of [12]successful builds is updated as new information becomes 4362 available. 4363 4364 The GCC developers would like to thank the numerous people that have 4365 contributed new features, improvements, bug fixes, and other changes as 4366 well as test results to GCC. This [13]amazing group of volunteers is 4367 what makes GCC successful. 4368 4369 For additional information about GCC please refer to the [14]GCC 4370 project web site or contact the [15]GCC development mailing list. 4371 4372 To obtain GCC please use [16]our mirror sites or [17]our version 4373 control system. 4374 4375 4376 For questions related to the use of GCC, please consult these web 4377 pages and the [18]GCC manuals. If that fails, the 4378 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 4379 web pages and the development of GCC are welcome on our developer 4380 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 4381 archives. 4382 4383 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 4384 distribution of this entire article is permitted in any medium, 4385 provided this notice is preserved. 4386 4387 These pages are [23]maintained by the GCC team. Last modified 4388 2022-10-26. 4389 4390 References 4391 4392 1. http://www.gnu.org/ 4393 2. http://gcc.gnu.org/gcc-6/changes.html 4394 3. http://gcc.gnu.org/onlinedocs/6.5.0/ 4395 4. http://gcc.gnu.org/gcc-6/changes.html 4396 5. http://gcc.gnu.org/onlinedocs/6.4.0/ 4397 6. http://gcc.gnu.org/gcc-6/changes.html 4398 7. http://gcc.gnu.org/onlinedocs/6.3.0/ 4399 8. http://gcc.gnu.org/gcc-6/changes.html 4400 9. http://gcc.gnu.org/onlinedocs/6.2.0/ 4401 10. http://gcc.gnu.org/gcc-6/changes.html 4402 11. http://gcc.gnu.org/onlinedocs/6.1.0/ 4403 12. http://gcc.gnu.org/gcc-6/buildstat.html 4404 13. http://gcc.gnu.org/onlinedocs/gcc/Contributors.html 4405 14. http://gcc.gnu.org/index.html 4406 15. mailto:gcc (a] gcc.gnu.org 4407 16. http://gcc.gnu.org/mirrors.html 4408 17. http://gcc.gnu.org/git.html 4409 18. https://gcc.gnu.org/onlinedocs/ 4410 19. mailto:gcc-help (a] gcc.gnu.org 4411 20. mailto:gcc (a] gcc.gnu.org 4412 21. https://gcc.gnu.org/lists.html 4413 22. https://www.fsf.org/ 4414 23. https://gcc.gnu.org/about.html 4415 ====================================================================== 4416 http://gcc.gnu.org/gcc-6/changes.html 4417 4418 GCC 6 Release Series 4419 Changes, New Features, and Fixes 4420 4421 This page is a brief summary of some of the huge number of improvements 4422 in GCC 6. For more information, see the [1]Porting to GCC 6 page and 4423 the [2]full GCC documentation. 4424 4425 Caveats 4426 4427 * The default mode for C++ is now -std=gnu++14 instead of 4428 -std=gnu++98. 4429 * Support for a number of older systems and recently unmaintained or 4430 untested target ports of GCC has been declared obsolete in GCC 6. 4431 Unless there is activity to revive them, the next release of GCC 4432 will have their sources permanently removed. 4433 The following ports for individual systems on particular 4434 architectures have been obsoleted: 4435 + SH5 / SH64 (sh64-*-*) as announced [3]here. 4436 * The AVR port requires binutils version 2.26.1 or later for the fix 4437 for [4]PR71151 to work. 4438 * The GCC 6.5 release has an accidental ABI incompatibility for 4439 nested std::pair objects, for more details see [5]PR 87822. The bug 4440 causes a layout change for pairs where the first member is also a 4441 pair, e.g. std::pair<std::pair<X, Y>, Z>. The GCC 6 release series 4442 is closed so the bug in GCC 6.5 will not be fixed upstream, but 4443 there is a patch in the bug report to allow it to be fixed by 4444 anybody packaging GCC 6.5 or installing it themselves. 4445 4446 General Optimizer Improvements 4447 4448 * UndefinedBehaviorSanitizer gained a new sanitization option, 4449 -fsanitize=bounds-strict, which enables strict checking of array 4450 bounds. In particular, it enables -fsanitize=bounds as well as 4451 instrumentation of flexible array member-like arrays. 4452 * Type-based alias analysis now disambiguates accesses to different 4453 pointers. This improves precision of the alias oracle by about 4454 20-30% on higher-level C++ programs. Programs doing invalid type 4455 punning of pointer types may now need -fno-strict-aliasing to work 4456 correctly. 4457 * Alias analysis now correctly supports the weakref and alias 4458 attributes. This allows accessing both a variable and its alias in 4459 one translation unit which is common with link-time optimization. 4460 * Value range propagation now assumes that the this pointer in C++ 4461 member functions is non-null. This eliminates common null pointer 4462 checks but also breaks some non-conforming code-bases (such as 4463 Qt-5, Chromium, KDevelop). As a temporary work-around 4464 -fno-delete-null-pointer-checks can be used. Wrong code can be 4465 identified by using -fsanitize=undefined. 4466 * Link-time optimization improvements: 4467 + warning and error attributes are now correctly preserved by 4468 declaration linking and thus -D_FORTIFY_SOURCE=2 is now 4469 supported with -flto. 4470 + Type merging was fixed to handle C and Fortran 4471 interoperability rules as defined by the Fortran 2008 language 4472 standard. 4473 As an exception, CHARACTER(KIND=C_CHAR) is not inter-operable 4474 with char in all cases because it is an array while char is 4475 scalar. INTEGER(KIND=C_SIGNED_CHAR) should be used instead. In 4476 general, this inter-operability cannot be implemented, for 4477 example on targets where the argument passing convention for 4478 arrays differs from scalars. 4479 + More type information is now preserved at link time, reducing 4480 the loss of accuracy of the type-based alias analysis compared 4481 to builds without link-time optimization. 4482 + Invalid type punning on global variables and declarations is 4483 now reported with -Wodr-type-mismatch. 4484 + The size of LTO object files was reduced by about 11% 4485 (measured by compiling Firefox 46.0). 4486 + Link-time parallelization (enabled using -flto=n) was 4487 significantly improved by decreasing the size of streamed data 4488 when partitioning programs. The size of streamed IL while 4489 compiling Firefox 46.0 was reduced by 66%. 4490 + The linker plugin was extended to pass information about the 4491 type of binary produced to the GCC back end. (That can also be 4492 controlled manually by -flinker-output.) This makes it 4493 possible to properly configure the code generator and support 4494 incremental linking. Incremental linking of LTO objects by gcc 4495 -r is now supported for plugin-enabled setups. 4496 There are two ways to perform incremental linking: 4497 1. Linking by ld -r will result in an object file with all 4498 sections from individual object files mechanically 4499 merged. This delays the actual link-time optimization to 4500 the final linking step and thus permits whole program 4501 optimization. Linking the final binary with such object 4502 files is however slower. 4503 2. Linking by gcc -r will lead to link-time optimization and 4504 emit the final binary into the object file. Linking such 4505 an object file is fast but avoids any benefits from whole 4506 program optimization. 4507 GCC 7 will support incremental link-time optimization with gcc 4508 -r. 4509 * Inter-procedural optimization improvements: 4510 + Basic jump threading is now performed before profile 4511 construction and inline analysis, resulting in more realistic 4512 size and time estimates that drive the heuristics of the 4513 inliner and function cloning passes. 4514 + Function cloning now more aggressively eliminates unused 4515 function parameters. 4516 4517 New Languages and Language specific improvements 4518 4519 Compared to GCC 5, the GCC 6 release series includes a much improved 4520 implementation of the [6]OpenACC 2.0a specification. Highlights are: 4521 * In addition to single-threaded host-fallback execution, offloading 4522 is supported for nvptx (Nvidia GPUs) on x86_64 and PowerPC 64-bit 4523 little-endian GNU/Linux host systems. For nvptx offloading, with 4524 the OpenACC parallel construct, the execution model allows for an 4525 arbitrary number of gangs, up to 32 workers, and 32 vectors. 4526 * Initial support for parallelized execution of OpenACC kernels 4527 constructs: 4528 + Parallelization of a kernels region is switched on by 4529 -fopenacc combined with -O2 or higher. 4530 + Code is offloaded onto multiple gangs, but executes with just 4531 one worker, and a vector length of 1. 4532 + Directives inside a kernels region are not supported. 4533 + Loops with reductions can be parallelized. 4534 + Only kernels regions with one loop nest are parallelized. 4535 + Only the outer-most loop of a loop nest can be parallelized. 4536 + Loop nests containing sibling loops are not parallelized. 4537 Typically, using the OpenACC parallel construct gives much better 4538 performance, compared to the initial support of the OpenACC kernels 4539 construct. 4540 * The device_type clause is not supported. The bind and nohost 4541 clauses are not supported. The host_data directive is not supported 4542 in Fortran. 4543 * Nested parallelism (cf. CUDA dynamic parallelism) is not supported. 4544 * Usage of OpenACC constructs inside multithreaded contexts (such as 4545 created by OpenMP, or pthread programming) is not supported. 4546 * If a call to the acc_on_device function has a compile-time constant 4547 argument, the function call evaluates to a compile-time constant 4548 value only for C and C++ but not for Fortran. 4549 4550 See the [7]OpenACC and [8]Offloading wiki pages for further 4551 information. 4552 4553 C family 4554 4555 * Version 4.5 of the [9]OpenMP specification is now supported in the 4556 C and C++ compilers. 4557 * The C and C++ compilers now support attributes on enumerators. For 4558 instance, it is now possible to mark enumerators as deprecated: 4559 4560 enum { 4561 newval, 4562 oldval __attribute__ ((deprecated ("too old"))) 4563 }; 4564 4565 * Source locations for the C and C++ compilers are now tracked as 4566 ranges, rather than just points, making it easier to identify the 4567 subexpression of interest within a complicated expression. For 4568 example: 4569 4570 test.cc: In function 'int test(int, int, foo, int, int)': 4571 test.cc:5:16: error: no match for 'operator*' (operand types are 'int' and 'foo' 4572 ) 4573 return p + q * r * s + t; 4574 ~~^~~ 4575 4576 In addition, there is now initial support for precise diagnostic 4577 locations within strings: 4578 4579 format-strings.c:3:14: warning: field width specifier '*' expects a matching 'in 4580 t' argument [-Wformat=] 4581 printf("%*d"); 4582 ^ 4583 4584 * Diagnostics can now contain "fix-it hints", which are displayed in 4585 context underneath the relevant source code. For example: 4586 4587 fixits.c: In function 'bad_deref': 4588 fixits.c:11:13: error: 'ptr' is a pointer; did you mean to use '->'? 4589 return ptr.x; 4590 ^ 4591 -> 4592 4593 * The C and C++ compilers now offer suggestions for misspelled field 4594 names: 4595 4596 spellcheck-fields.cc:52:13: error: 'struct s' has no member named 'colour'; did 4597 you mean 'color'? 4598 return ptr->colour; 4599 ^~~~~~ 4600 4601 * New command-line options have been added for the C and C++ 4602 compilers: 4603 + -Wshift-negative-value warns about left shifting a negative 4604 value. 4605 + -Wshift-overflow warns about left shift overflows. This 4606 warning is enabled by default. -Wshift-overflow=2 also warns 4607 about left-shifting 1 into the sign bit. 4608 + -Wtautological-compare warns if a self-comparison always 4609 evaluates to true or false. This warning is enabled by -Wall. 4610 + -Wnull-dereference warns if the compiler detects paths that 4611 trigger erroneous or undefined behavior due to dereferencing a 4612 null pointer. This option is only active when 4613 -fdelete-null-pointer-checks is active, which is enabled by 4614 optimizations in most targets. The precision of the warnings 4615 depends on the optimization options used. 4616 + -Wduplicated-cond warns about duplicated conditions in an 4617 if-else-if chain. 4618 + -Wmisleading-indentation warns about places where the 4619 indentation of the code gives a misleading idea of the block 4620 structure of the code to a human reader. For example, given 4621 [10]CVE-2014-1266: 4622 4623 sslKeyExchange.c: In function 'SSLVerifySignedServerKeyExchange': 4624 sslKeyExchange.c:629:3: warning: this 'if' clause does not guard... [-Wmisleadin 4625 g-indentation] 4626 if ((err = SSLHashSHA1.update(&hashCtx, &signedParams)) != 0) 4627 ^~ 4628 sslKeyExchange.c:631:5: note: ...this statement, but the latter is misleadingly 4629 indented as if it is guarded by the 'if' 4630 goto fail; 4631 ^~~~ 4632 4633 This warning is enabled by -Wall. 4634 * The C and C++ compilers now emit saner error messages if 4635 merge-conflict markers are present in a source file. 4636 4637 test.c:3:1: error: version control conflict marker in file 4638 <<<<<<< HEAD 4639 ^~~~~~~ 4640 4641 C 4642 4643 * It is possible to disable warnings when an initialized field of a 4644 structure or a union with side effects is being overridden when 4645 using designated initializers via a new warning option 4646 -Woverride-init-side-effects. 4647 * A new type attribute scalar_storage_order applying to structures 4648 and unions has been introduced. It specifies the storage order (aka 4649 endianness) in memory of scalar fields in structures or unions. 4650 4651 C++ 4652 4653 * The default mode has been changed to -std=gnu++14. 4654 * [11]C++ Concepts are now supported when compiling with -fconcepts. 4655 * -flifetime-dse is more aggressive in dead-store elimination in 4656 situations where a memory store to a location precedes a 4657 constructor to that memory location. 4658 * G++ now supports [12]C++17 fold expressions, u8 character literals, 4659 extended static_assert, and nested namespace definitions. 4660 * G++ now allows constant evaluation for all non-type template 4661 arguments. 4662 * G++ now supports C++ Transactional Memory when compiling with 4663 -fgnu-tm. 4664 4665 Runtime Library (libstdc++) 4666 4667 * Extensions to the C++ Library to support mathematical special 4668 functions (ISO/IEC 29124:2010), thanks to Edward Smith-Rowland. 4669 * Experimental support for C++17, including the following new 4670 features: 4671 + std::uncaught_exceptions function (this is also available for 4672 -std=gnu++NN modes); 4673 + new member functions try_emplace and insert_or_assign for 4674 unique_key maps; 4675 + non-member functions std::size, std::empty, and std::data for 4676 accessing containers and arrays; 4677 + std::invoke; 4678 + std::shared_mutex; 4679 + std::void_t and std::bool_constant metaprogramming utilities. 4680 Thanks to Ville Voutilainen for contributing many of the C++17 4681 features. 4682 * An experimental implementation of the File System TS. 4683 * Experimental support for most features of the second version of the 4684 Library Fundamentals TS. This includes polymorphic memory resources 4685 and array support in shared_ptr, thanks to Fan You. 4686 * Some assertions checked by Debug Mode can now also be enabled by 4687 _GLIBCXX_ASSERTIONS. The subset of checks enabled by the new macro 4688 have less run-time overhead than the full _GLIBCXX_DEBUG checks and 4689 don't affect the library ABI, so can be enabled per-translation 4690 unit. 4691 * Timed mutex types are supported on more targets, including Darwin. 4692 * Improved std::locale support for DragonFly and FreeBSD, thanks to 4693 John Marino and Andreas Tobler. 4694 4695 Fortran 4696 4697 * Fortran 2008 SUBMODULE support. 4698 * Fortran 2015 EVENT_TYPE, EVENT_POST, EVENT_WAIT, and EVENT_QUERY 4699 support. 4700 * Improved support for Fortran 2003 deferred-length character 4701 variables. 4702 * Improved support for OpenMP and OpenACC. 4703 * The MATMUL intrinsic is now inlined for straightforward cases if 4704 front-end optimization is active. The maximum size for inlining can 4705 be set to n with the -finline-matmul-limit=n option and turned off 4706 with -finline-matmul-limit=0. 4707 * The -Wconversion-extra option will warn about REAL constants which 4708 have excess precision for their kind. 4709 * The -Winteger-division option has been added, which warns about 4710 divisions of integer constants which are truncated. This option is 4711 included in -Wall by default. 4712 4713 libgccjit 4714 4715 * The driver code is now run in-process within libgccjit, providing a 4716 small speed-up of the compilation process. 4717 * The API has gained entrypoints for 4718 + [13]timing how long was spent in different parts of code, 4719 + [14]creating switch statements, 4720 + [15]allowing unreachable basic blocks in a function, and 4721 + [16]adding arbitrary command-line options to a compilation. 4722 4723 New Targets and Target Specific Improvements 4724 4725 AArch64 4726 4727 * A number of AArch64-specific options have been added. The most 4728 important ones are summarised in this section; for more detailed 4729 information please refer to the documentation. 4730 * The command-line options -march=native, -mcpu=native and 4731 -mtune=native are now available on native AArch64 GNU/Linux 4732 systems. Specifying these options causes GCC to auto-detect the 4733 host CPU and choose the optimal setting for that system. 4734 * -fpic is now supported when generating code for the small code 4735 model (-mcmodel=small). The size of the global offset table (GOT) 4736 is limited to 28KiB under the LP64 SysV ABI, and 15KiB under the 4737 ILP32 SysV ABI. 4738 * The AArch64 port now supports target attributes and pragmas. Please 4739 refer to the [17]documentation for details of available attributes 4740 and pragmas as well as usage instructions. 4741 * Link-time optimization across translation units with different 4742 target-specific options is now supported. 4743 * The option -mtls-size= is now supported. It can be used to specify 4744 the bit size of TLS offsets, allowing GCC to generate better TLS 4745 instruction sequences. 4746 * The option -fno-plt is now fully functional. 4747 * The ARMv8.1-A architecture and the Large System Extensions are now 4748 supported. They can be used by specifying the -march=armv8.1-a 4749 option. Additionally, the +lse option extension can be used in a 4750 similar fashion to other option extensions. The Large System 4751 Extensions introduce new instructions that are used in the 4752 implementation of atomic operations. 4753 * The ACLE half-precision floating-point type __fp16 is now supported 4754 in the C and C++ languages. 4755 * The ARM Cortex-A35 processor is now supported via the 4756 -mcpu=cortex-a35 and -mtune=cortex-a35 options as well as the 4757 equivalent target attributes and pragmas. 4758 * The Qualcomm QDF24xx processor is now supported via the 4759 -mcpu=qdf24xx and -mtune=qdf24xx options as well as the equivalent 4760 target attributes and pragmas. 4761 * Code generation for the ARM Cortex-A57 processor is improved. Among 4762 general code generation improvements, a better algorithm is added 4763 for allocating registers to floating-point multiply-accumulate 4764 instructions offering increased performance when compiling with 4765 -mcpu=cortex-a57 or -mtune=cortex-a57. 4766 * Code generation for the ARM Cortex-A53 processor is improved. A 4767 more accurate instruction scheduling model for the processor is now 4768 used, and a number of compiler tuning parameters have been set to 4769 offer increased performance when compiling with -mcpu=cortex-a53 or 4770 -mtune=cortex-a53. 4771 * Code generation for the Samsung Exynos M1 processor is improved. A 4772 more accurate instruction scheduling model for the processor is now 4773 used, and a number of compiler tuning parameters have been set to 4774 offer increased performance when compiling with -mcpu=exynos-m1 or 4775 -mtune=exynos-m1. 4776 * Improvements in the generation of conditional branches and literal 4777 pools allow the compiler to compile functions of a large size. 4778 Constant pools are now placed into separate rodata sections. The 4779 new option -mpc-relative-literal-loads generates per-function 4780 literal pools, limiting the maximum size of functions to 1MiB. 4781 * Several correctness issues generating Advanced SIMD instructions 4782 for big-endian targets have been fixed resulting in improved code 4783 generation for ACLE intrinsics with -mbig-endian. 4784 4785 ARM 4786 4787 * Support for revisions of the ARM architecture prior to ARMv4t has 4788 been deprecated and will be removed in a future GCC release. The 4789 -mcpu and -mtune values that are deprecated are: arm2, arm250, 4790 arm3, arm6, arm60, arm600, arm610, arm620, arm7, arm7d, arm7di, 4791 arm70, arm700, arm700i, arm710, arm720, arm710c, arm7100, arm7500, 4792 arm7500fe, arm7m, arm7dm, arm7dmi, arm8, arm810, strongarm, 4793 strongarm110, strongarm1100, strongarm1110, fa526, fa626. The value 4794 arm7tdmi is still supported. The values of -march that are 4795 deprecated are: armv2,armv2a,armv3,armv3m,armv4. 4796 * The ARM port now supports target attributes and pragmas. Please 4797 refer to the [18]documentation for details of available attributes 4798 and pragmas as well as usage instructions. 4799 * Support has been added for the following processors (GCC 4800 identifiers in parentheses): ARM Cortex-A32 (cortex-a32), ARM 4801 Cortex-A35 (cortex-a35) and ARM Cortex-R8 (cortex-r8). The GCC 4802 identifiers can be used as arguments to the -mcpu or -mtune 4803 options, for example: -mcpu=cortex-a32 or -mtune=cortex-a35. 4804 4805 Heterogeneous Systems Architecture 4806 4807 * GCC can now generate HSAIL (Heterogeneous System Architecture 4808 Intermediate Language) for simple OpenMP device constructs if 4809 configured with --enable-offload-targets=hsa. A new libgomp plugin 4810 then runs the HSA GPU kernels implementing these constructs on HSA 4811 capable GPUs via a standard HSA run time. 4812 If the HSA compilation back end determines it cannot output HSAIL 4813 for a particular input, it gives a warning by default. These 4814 warnings can be suppressed with -Wno-hsa. To give a few examples, 4815 the HSA back end does not implement compilation of code using 4816 function pointers, automatic allocation of variable sized arrays, 4817 functions with variadic arguments as well as a number of other less 4818 common programming constructs. 4819 When compilation for HSA is enabled, the compiler attempts to 4820 compile composite OpenMP constructs 4821 4822 #pragma omp target teams distribute parallel for 4823 4824 into parallel HSA GPU kernels. 4825 4826 IA-32/x86-64 4827 4828 * GCC now supports the Intel CPU named Skylake with AVX-512 4829 extensions through -march=skylake-avx512. The switch enables the 4830 following ISA extensions: AVX-512F, AVX512VL, AVX-512CD, AVX-512BW, 4831 AVX-512DQ. 4832 * Support for new AMD instructions monitorx and mwaitx has been 4833 added. This includes new intrinsic and built-in support. It is 4834 enabled through option -mmwaitx. The instructions monitorx and 4835 mwaitx implement the same functionality as the old monitor and 4836 mwait instructions. In addition, mwaitx adds a configurable timer. 4837 The timer value is received as third argument and stored in 4838 register %ebx. 4839 * x86-64 targets now allow stack realignment from a word-aligned 4840 stack pointer using the command-line option -mstackrealign or 4841 __attribute__ ((force_align_arg_pointer)). This allows functions 4842 compiled with a vector-aligned stack to be invoked from objects 4843 that keep only word-alignment. 4844 * Support for address spaces __seg_fs, __seg_gs, and __seg_tls. These 4845 can be used to access data via the %fs and %gs segments without 4846 having to resort to inline assembly. Please refer to the 4847 [19]documentation for usage instructions. 4848 * Support for AMD Zen (family 17h) processors is now available 4849 through the -march=znver1 and -mtune=znver1 options. 4850 4851 MeP 4852 4853 * Support for the MeP (mep-elf) architecture has been deprecated and 4854 will be removed in a future GCC release. 4855 4856 MSP430 4857 4858 * The MSP430 compiler now has the ability to automatically distribute 4859 code and data between low memory (addresses below 64K) and high 4860 memory. This only applies to parts that actually have both memory 4861 regions and only if the linker script for the part has been 4862 specifically set up to support this feature. 4863 A new attribute of either can be applied to both functions and 4864 data, and this tells the compiler to place the object into low 4865 memory if there is room and into high memory otherwise. Two other 4866 new attributes - lower and upper - can be used to explicitly state 4867 that an object should be placed in the specified memory region. If 4868 there is not enough left in that region the compilation will fail. 4869 Two new command-line options - -mcode-region=[lower|upper|either] 4870 and -mdata-region=[lower|upper|either] - can be used to tell the 4871 compiler what to do with objects that do not have one of these new 4872 attributes. 4873 4874 PowerPC / PowerPC64 / RS6000 4875 4876 * PowerPC64 now supports IEEE 128-bit floating-point using the 4877 __float128 data type. In GCC 6, this is not enabled by default, but 4878 you can enable it with -mfloat128. The IEEE 128-bit floating-point 4879 support requires the use of the VSX instruction set. IEEE 128-bit 4880 floating-point values are passed and returned as a single vector 4881 value. The software emulator for IEEE 128-bit floating-point 4882 support is only built on PowerPC GNU/Linux systems where the 4883 default CPU is at least power7. On future ISA 3.0 systems (POWER 9 4884 and later), you will be able to use the -mfloat128-hardware option 4885 to use the ISA 3.0 instructions that support IEEE 128-bit 4886 floating-point. An additional type (__ibm128) has been added to 4887 refer to the IBM extended double type that normally implements long 4888 double. This will allow for a future transition to implementing 4889 long double with IEEE 128-bit floating-point. 4890 * Basic support has been added for POWER9 hardware that will use the 4891 recently published OpenPOWER ISA 3.0 instructions. The following 4892 new switches are available: 4893 + -mcpu=power9: Implement all of the ISA 3.0 instructions 4894 supported by the compiler. 4895 + -mtune=power9: In the future, apply tuning for POWER9 systems. 4896 Currently, POWER8 tunings are used. 4897 + -mmodulo: Generate code using the ISA 3.0 integer instructions 4898 (modulus, count trailing zeros, array index support, integer 4899 multiply/add). 4900 + -mpower9-fusion: Generate code to suitably fuse instruction 4901 sequences for a POWER9 system. 4902 + -mpower9-dform: Generate code to use the new D-form 4903 (register+offset) memory instructions for the vector 4904 registers. 4905 + -mpower9-vector: Generate code using the new ISA 3.0 vector 4906 (VSX or Altivec) instructions. 4907 + -mpower9-minmax: Reserved for future development. 4908 + -mtoc-fusion: Keep TOC entries together to provide more fusion 4909 opportunities. 4910 * New constraints have been added to support IEEE 128-bit 4911 floating-point and ISA 3.0 instructions: 4912 + wb: Altivec register if -mpower9-dform is enabled. 4913 + we: VSX register if -mpower9-vector is enabled for 64-bit code 4914 generation. 4915 + wo: VSX register if -mpower9-vector is enabled. 4916 + wp: Reserved for future use if long double is implemented with 4917 IEEE 128-bit floating-point instead of IBM extended double. 4918 + wq: VSX register if -mfloat128 is enabled. 4919 + wF: Memory operand suitable for POWER9 fusion load/store. 4920 + wG: Memory operand suitable for TOC fusion memory references. 4921 + wL: Integer constant identifying the element number mfvsrld 4922 accesses within a vector. 4923 * Support has been added for __builtin_cpu_is() and 4924 __builtin_cpu_supports(), allowing for very fast access to 4925 AT_PLATFORM, AT_HWCAP, and AT_HWCAP2 values. This requires use of 4926 glibc 2.23 or later. 4927 * All hardware transactional memory builtins now correctly behave as 4928 memory barriers. Programmers can use #ifdef __TM_FENCE__ to 4929 determine whether their "old" compiler treats the builtins as 4930 barriers. 4931 * Split-stack support has been added for gccgo on PowerPC64 for both 4932 big- and little-endian (but not for 32-bit). The gold linker from 4933 at least binutils 2.25.1 must be available in the PATH when 4934 configuring and building gccgo to enable split stack. (The 4935 requirement for binutils 2.25.1 applies to PowerPC64 only.) The 4936 split-stack feature allows a small initial stack size to be 4937 allocated for each goroutine, which increases as needed. 4938 * GCC on PowerPC now supports the standard lround function. 4939 * A new configuration option ---with-advance-toolchain=at was added 4940 for PowerPC 64-bit GNU/Linux systems to use the header files, 4941 library files, and the dynamic linker from a specific Advance 4942 Toolchain release instead of the default versions that are provided 4943 by the GNU/Linux distribution. In general, this option is intended 4944 for the developers of GCC, and it is not intended for general use. 4945 * The "q", "S", "T", and "t" asm-constraints have been removed. 4946 * The "b", "B", "m", "M", and "W" format modifiers have been removed. 4947 4948 S/390, System z, IBM z Systems 4949 4950 * Support for the IBM z13 processor has been added. When using the 4951 -march=z13 option, the compiler will generate code making use of 4952 the new instructions and registers introduced with the vector 4953 extension facility. The -mtune=z13 option enables z13 specific 4954 instruction scheduling without making use of new instructions. 4955 Compiling code with -march=z13 reduces the default alignment of 4956 vector types bigger than 8 bytes to 8. This is an ABI change and 4957 care must be taken when linking modules compiled with different 4958 arch levels which interchange variables containing vector type 4959 values. For newly compiled code the GNU linker will emit a warning. 4960 * The -mzvector option enables a C/C++ language extension. This 4961 extension provides a new keyword vector which can be used to define 4962 vector type variables. (Note: This is not available when enforcing 4963 strict standard compliance e.g. with -std=c99. Either enable GNU 4964 extensions with e.g. -std=gnu99 or use __vector instead of vector.) 4965 Additionally a set of overloaded builtins is provided which is 4966 partially compatible to the PowerPC Altivec builtins. In order to 4967 make use of these builtins the vecintrin.h header file needs to be 4968 included. 4969 * The new command-line options -march=native, and -mtune=native are 4970 now available on native IBM z Systems. Specifying these options 4971 causes GCC to auto-detect the host CPU and choose the optimal 4972 setting for that system. If GCC is unable to detect the host CPU 4973 these options have no effect. 4974 * The IBM z Systems port now supports target attributes and pragmas. 4975 Please refer to the [20]documentation for details of available 4976 attributes and pragmas as well as usage instructions. 4977 * -fsplit-stack is now supported as part of the IBM z Systems port. 4978 This feature requires a recent gold linker to be used. 4979 * Support for the g5 and g6 -march=/-mtune= CPU level switches has 4980 been deprecated and will be removed in a future GCC release. -m31 4981 from now on defaults to -march=z900 if not specified otherwise. 4982 -march=native on a g5/g6 machine will default to -march=z900. 4983 4984 SH 4985 4986 * Support for SH5 / SH64 has been declared obsolete and will be 4987 removed in future releases. 4988 * Support for the FDPIC ABI has been added. It can be enabled using 4989 the new -mfdpic target option and --enable-fdpic configure option. 4990 4991 SPARC 4992 4993 * An ABI bug has been fixed in 64-bit mode. Unfortunately, this 4994 change will break binary compatibility with earlier releases for 4995 code it affects, but this should be pretty rare in practice. The 4996 conditions are: a 16-byte structure containing a double or a 8-byte 4997 vector in the second half is passed to a subprogram in slot #15, 4998 for example as 16th parameter if the first 15 ones have at most 8 4999 bytes. The double or vector was wrongly passed in floating-point 5000 register %d32 in lieu of on the stack as per the SPARC calling 5001 conventions. 5002 5003 Operating Systems 5004 5005 AIX 5006 5007 * DWARF debugging support for AIX 7.1 has been enabled as an optional 5008 debugging format. A more recent Technology Level (TL) and GCC built 5009 with that level are required for full exploitation of DWARF 5010 debugging capabilities. 5011 5012 Linux 5013 5014 * Support for the [21]musl C library was added for the AArch64, ARM, 5015 MicroBlaze, MIPS, MIPS64, PowerPC, PowerPC64, SH, i386, x32 and 5016 x86_64 targets. It can be selected using the new -mmusl option in 5017 case musl is not the default libc. GCC defaults to musl libc if it 5018 is built with a target triplet matching the *-linux-musl* pattern. 5019 5020 RTEMS 5021 5022 * The RTEMS thread model implementation changed. Mutexes now use 5023 self-contained objects defined in newlib <sys/lock.h> instead of 5024 Classic API semaphores. The keys for thread specific data and the 5025 once function are directly defined via <pthread.h>. Self-contained 5026 condition variables are provided via newlib <sys/lock.h>. The RTEMS 5027 thread model also supports C++11 threads. 5028 * OpenMP support now uses self-contained objects provided by newlib 5029 <sys/lock.h> and offers a significantly better performance compared 5030 to the POSIX configuration of libgomp. It is possible to configure 5031 thread pools for each scheduler instance via the environment 5032 variable GOMP_RTEMS_THREAD_POOLS. 5033 5034 Solaris 5035 5036 * Solaris 12 is now fully supported. Minimal support had already been 5037 present in GCC 5.3. 5038 * Solaris 12 provides a full set of startup files (crt1.o, crti.o, 5039 crtn.o), which GCC now prefers over its own ones. 5040 * Position independent executables (PIE) are now supported on Solaris 5041 12. 5042 * Constructor priority is now supported on Solaris 12 with the system 5043 linker. 5044 * libvtv has been ported to Solaris 11 and up. 5045 5046 Windows 5047 5048 * The option -mstackrealign is now automatically activated in 32-bit 5049 mode whenever the use of SSE instructions is requested. 5050 5051 Other significant improvements 5052 5053 * The gcc and g++ driver programs will now provide suggestions for 5054 misspelled command-line options. 5055 5056 $ gcc -static-libfortran test.f95 5057 gcc: error: unrecognized command line option '-static-libfortran'; did you mean 5058 '-static-libgfortran'? 5059 5060 * The --enable-default-pie configure option enables generation of PIE 5061 by default. 5062 5063 GCC 6.2 5064 5065 This is the [22]list of problem reports (PRs) from GCC's bug tracking 5066 system that are known to be fixed in the 6.2 release. This list might 5067 not be complete (that is, it is possible that some PRs that have been 5068 fixed are not listed here). 5069 5070 Target Specific Changes 5071 5072 SPARC 5073 5074 * Support for --with-cpu-32 and --with-cpu-64 configure options has 5075 been added on bi-architecture platforms. 5076 * Support for the SPARC M7 (Niagara 7) processor has been added. 5077 * Support for the VIS 4.0 instruction set has been added. 5078 5079 GCC 6.3 5080 5081 This is the [23]list of problem reports (PRs) from GCC's bug tracking 5082 system that are known to be fixed in the 6.3 release. This list might 5083 not be complete (that is, it is possible that some PRs that have been 5084 fixed are not listed here). 5085 5086 Target Specific Changes 5087 5088 IA-32/x86-64 5089 5090 * Support for the [24]deprecated pcommit instruction has been 5091 removed. 5092 5093 GCC 6.4 5094 5095 This is the [25]list of problem reports (PRs) from GCC's bug tracking 5096 system that are known to be fixed in the 6.4 release. This list might 5097 not be complete (that is, it is possible that some PRs that have been 5098 fixed are not listed here). 5099 5100 Operating Systems 5101 5102 RTEMS 5103 5104 * The ABI changes on ARM so that no short enums are used by default. 5105 5106 GCC 6.5 5107 5108 This is the [26]list of problem reports (PRs) from GCC's bug tracking 5109 system that are known to be fixed in the 6.5 release. This list might 5110 not be complete (that is, it is possible that some PRs that have been 5111 fixed are not listed here). 5112 5113 5114 For questions related to the use of GCC, please consult these web 5115 pages and the [27]GCC manuals. If that fails, the 5116 [28]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 5117 web pages and the development of GCC are welcome on our developer 5118 list at [29]gcc (a] gcc.gnu.org. All of [30]our lists have public 5119 archives. 5120 5121 Copyright (C) [31]Free Software Foundation, Inc. Verbatim copying and 5122 distribution of this entire article is permitted in any medium, 5123 provided this notice is preserved. 5124 5125 These pages are [32]maintained by the GCC team. Last modified 5126 2023-02-20. 5127 5128 References 5129 5130 1. http://gcc.gnu.org/gcc-6/porting_to.html 5131 2. http://gcc.gnu.org/onlinedocs/index.html#current 5132 3. https://gcc.gnu.org/ml/gcc/2015-08/msg00101.html 5133 4. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71151 5134 5. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87822 5135 6. https://www.openacc.org/ 5136 7. https://gcc.gnu.org/wiki/OpenACC 5137 8. https://gcc.gnu.org/wiki/Offloading 5138 9. https://www.openmp.org/specifications/ 5139 10. https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-1266 5140 11. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4377.pdf 5141 12. https://gcc.gnu.org/projects/cxx-status.html#cxx1z 5142 13. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/jit/topics/performance.html 5143 14. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/jit/topics/functions.html#gcc_jit_block_end_with_switch 5144 15. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/jit/topics/contexts.html#gcc_jit_context_set_bool_allow_unreachable_blocks 5145 16. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/jit/topics/contexts.html#gcc_jit_context_add_command_line_option 5146 17. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/gcc/AArch64-Function-Attributes.html#AArch64-Function-Attributes 5147 18. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/gcc/ARM-Function-Attributes.html#ARM-Function-Attributes 5148 19. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/gcc/Named-Address-Spaces.html#Named-Address-Spaces 5149 20. https://gcc.gnu.org/onlinedocs/gcc-6.1.0/gcc/S_002f390-Function-Attributes.html#S_002f390-Function-Attributes 5150 21. http://www.musl-libc.org/ 5151 22. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=6.2 5152 23. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=6.3 5153 24. https://www.intel.com/content/www/us/en/developer/articles/technical/deprecate-pcommit-instruction.html 5154 25. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=6.4 5155 26. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=6.5 5156 27. https://gcc.gnu.org/onlinedocs/ 5157 28. mailto:gcc-help (a] gcc.gnu.org 5158 29. mailto:gcc (a] gcc.gnu.org 5159 30. https://gcc.gnu.org/lists.html 5160 31. https://www.fsf.org/ 5161 32. https://gcc.gnu.org/about.html 5162 ====================================================================== 5163 http://gcc.gnu.org/gcc-5/index.html 5164 5165 GCC 5 Release Series 5166 5167 (This release series is no longer supported.) 5168 5169 October 10, 2017 5170 5171 The [1]GNU project and the GCC developers are pleased to announce the 5172 release of GCC 5.5. 5173 5174 This release is a bug-fix release, containing fixes for regressions in 5175 GCC 5.4 relative to previous releases of GCC. 5176 5177 Release History 5178 5179 GCC 5.5 5180 October 10, 2017 ([2]changes, [3]documentation) 5181 5182 GCC 5.4 5183 June 3, 2016 ([4]changes, [5]documentation) 5184 5185 GCC 5.3 5186 December 4, 2015 ([6]changes, [7]documentation) 5187 5188 GCC 5.2 5189 July 16, 2015 ([8]changes, [9]documentation) 5190 5191 GCC 5.1 5192 April 22, 2015 ([10]changes, [11]documentation) 5193 5194 References and Acknowledgements 5195 5196 GCC used to stand for the GNU C Compiler, but since the compiler 5197 supports several other languages aside from C, it now stands for the 5198 GNU Compiler Collection. 5199 5200 A list of [12]successful builds is updated as new information becomes 5201 available. 5202 5203 The GCC developers would like to thank the numerous people that have 5204 contributed new features, improvements, bug fixes, and other changes as 5205 well as test results to GCC. This [13]amazing group of volunteers is 5206 what makes GCC successful. 5207 5208 For additional information about GCC please refer to the [14]GCC 5209 project web site or contact the [15]GCC development mailing list. 5210 5211 To obtain GCC please use [16]our mirror sites or [17]our version 5212 control system. 5213 5214 5215 For questions related to the use of GCC, please consult these web 5216 pages and the [18]GCC manuals. If that fails, the 5217 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 5218 web pages and the development of GCC are welcome on our developer 5219 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 5220 archives. 5221 5222 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 5223 distribution of this entire article is permitted in any medium, 5224 provided this notice is preserved. 5225 5226 These pages are [23]maintained by the GCC team. Last modified 5227 2022-10-26. 5228 5229 References 5230 5231 1. http://www.gnu.org/ 5232 2. http://gcc.gnu.org/gcc-5/changes.html 5233 3. http://gcc.gnu.org/onlinedocs/5.5.0/ 5234 4. http://gcc.gnu.org/gcc-5/changes.html 5235 5. http://gcc.gnu.org/onlinedocs/5.4.0/ 5236 6. http://gcc.gnu.org/gcc-5/changes.html 5237 7. http://gcc.gnu.org/onlinedocs/5.3.0/ 5238 8. http://gcc.gnu.org/gcc-5/changes.html 5239 9. http://gcc.gnu.org/onlinedocs/5.2.0/ 5240 10. http://gcc.gnu.org/gcc-5/changes.html 5241 11. http://gcc.gnu.org/onlinedocs/5.1.0/ 5242 12. http://gcc.gnu.org/gcc-5/buildstat.html 5243 13. http://gcc.gnu.org/onlinedocs/gcc/Contributors.html 5244 14. http://gcc.gnu.org/index.html 5245 15. mailto:gcc (a] gcc.gnu.org 5246 16. http://gcc.gnu.org/mirrors.html 5247 17. http://gcc.gnu.org/git.html 5248 18. https://gcc.gnu.org/onlinedocs/ 5249 19. mailto:gcc-help (a] gcc.gnu.org 5250 20. mailto:gcc (a] gcc.gnu.org 5251 21. https://gcc.gnu.org/lists.html 5252 22. https://www.fsf.org/ 5253 23. https://gcc.gnu.org/about.html 5254 ====================================================================== 5255 http://gcc.gnu.org/gcc-5/changes.html 5256 5257 GCC 5 Release Series 5258 Changes, New Features, and Fixes 5259 5260 Caveats 5261 5262 * The default mode for C is now -std=gnu11 instead of -std=gnu89. 5263 * The C++ runtime library (libstdc++) uses a new ABI by default (see 5264 [1]below). 5265 * The Graphite framework for loop optimizations no longer requires 5266 the CLooG library, only ISL version 0.14 (recommended) or 0.12.2. 5267 The installation manual contains more information about 5268 requirements to build GCC. 5269 * The non-standard C++0x type traits has_trivial_default_constructor, 5270 has_trivial_copy_constructor and has_trivial_copy_assign have been 5271 deprecated and will be removed in a future version. The standard 5272 C++11 traits is_trivially_default_constructible, 5273 is_trivially_copy_constructible and is_trivially_copy_assignable 5274 should be used instead. 5275 * On AVR, support has been added for the devices 5276 ATtiny4/5/9/10/20/40. This requires Binutils 2.25 or newer. 5277 * The AVR port uses a new scheme to describe supported devices: For 5278 each supported device the compiler provides a device-specific 5279 [2]spec file. If the compiler is used together with AVR-LibC, this 5280 requires at least GCC 5.2 and a version of AVR-LibC which 5281 implements [3]feature #44574. 5282 5283 General Optimizer Improvements 5284 5285 * Inter-procedural optimization improvements: 5286 + An Identical Code Folding (ICF) pass (controlled via 5287 -fipa-icf) has been added. Compared to the identical code 5288 folding performed by the Gold linker this pass does not 5289 require function sections. It also performs merging before 5290 inlining, so inter-procedural optimizations are aware of the 5291 code re-use. On the other hand not all unifications performed 5292 by a linker are doable by GCC which must honor aliasing 5293 information. During link-time optimization of Firefox, this 5294 pass unifies about 31000 functions, that is 14% overall. 5295 + The devirtualization pass was significantly improved by adding 5296 better support for speculative devirtualization and dynamic 5297 type detection. About 50% of virtual calls in Firefox are now 5298 speculatively devirtualized during link-time optimization. 5299 + A new comdat localization pass allows the linker to eliminate 5300 more dead code in presence of C++ inline functions. 5301 + Virtual tables are now optimized. Local aliases are used to 5302 reduce dynamic linking time of C++ virtual tables on ELF 5303 targets and data alignment has been reduced to limit data 5304 segment bloat. 5305 + A new -fno-semantic-interposition option can be used to 5306 improve code quality of shared libraries where interposition 5307 of exported symbols is not allowed. 5308 + Write-only variables are now detected and optimized out. 5309 + With profile feedback the function inliner can now bypass 5310 --param inline-insns-auto and --param inline-insns-single 5311 limits for hot calls. 5312 + The IPA reference pass was significantly sped up making it 5313 feasible to enable -fipa-reference with -fprofile-generate. 5314 This also solves a bottleneck seen when building Chromium with 5315 link-time optimization. 5316 + The symbol table and call-graph API was reworked to C++ and 5317 simplified. 5318 + The interprocedural propagation of constants now also 5319 propagates alignments of pointer parameters. This for example 5320 means that the vectorizer often does not need to generate loop 5321 prologues and epilogues to make up for potential 5322 misalignments. 5323 * Link-time optimization improvements: 5324 + One Definition Rule based merging of C++ types has been 5325 implemented. Type merging enables better devirtualization and 5326 alias analysis. Streaming extra information needed to merge 5327 types adds about 2-6% of memory size and object size increase. 5328 This can be controlled by -flto-odr-type-merging. 5329 + Command-line optimization and target options are now streamed 5330 on a per-function basis and honored by the link-time 5331 optimizer. This change makes link-time optimization a more 5332 transparent replacement of per-file optimizations. It is now 5333 possible to build projects that require different optimization 5334 settings for different translation units (such as -ffast-math, 5335 -mavx, or -finline). Contrary to earlier GCC releases, the 5336 optimization and target options passed on the link command 5337 line are ignored. 5338 Note that this applies only to those command-line options that 5339 can be passed to optimize and target attributes. Command-line 5340 options affecting global code generation (such as -fpic), 5341 warnings (such as -Wodr), optimizations affecting the way 5342 static variables are optimized (such as -fcommon), debug 5343 output (such as -g), and --param parameters can be applied 5344 only to the whole link-time optimization unit. In these cases, 5345 it is recommended to consistently use the same options at both 5346 compile time and link time. 5347 + GCC bootstrap now uses slim LTO object files. 5348 + Memory usage and link times were improved. Tree merging was 5349 sped up, memory usage of GIMPLE declarations and types was 5350 reduced, and, support for on-demand streaming of variable 5351 constructors was added. 5352 * Feedback directed optimization improvements: 5353 + A new auto-FDO mode uses profiles collected by low overhead 5354 profiling tools (perf) instead of more expensive program 5355 instrumentation (via -fprofile-generate). SPEC2006 benchmarks 5356 on x86-64 improve by 4.7% with auto-FDO and by 7.3% with 5357 traditional feedback directed optimization. 5358 + Profile precision was improved in presence of C++ inline and 5359 extern inline functions. 5360 + The new gcov-tool utility allows manipulating profiles. 5361 + Profiles are now more tolerant to source file changes (this 5362 can be controlled by --param profile-func-internal-id). 5363 * Register allocation improvements: 5364 + A new local register allocator (LRA) sub-pass, controlled by 5365 -flra-remat, implements control-flow sensitive global register 5366 rematerialization. Instead of spilling and restoring a 5367 register value, it is recalculated if it is profitable. The 5368 sub-pass improved SPEC2000 generated code by 1% and 0.5% 5369 correspondingly on ARM and x86-64. 5370 + Reuse of the PIC hard register, instead of using a fixed 5371 register, was implemented on x86/x86-64 targets. This improves 5372 generated PIC code performance as more hard registers can be 5373 used. Shared libraries can significantly benefit from this 5374 optimization. Currently it is switched on only for x86/x86-64 5375 targets. As RA infrastructure is already implemented for PIC 5376 register reuse, other targets might follow this in the future. 5377 + A simple form of inter-procedural RA was implemented. When it 5378 is known that a called function does not use caller-saved 5379 registers, save/restore code is not generated around the call 5380 for such registers. This optimization can be controlled by 5381 -fipa-ra 5382 + LRA is now much more effective at generating spills of general 5383 registers into vector registers instead of memory on 5384 architectures (e.g., modern Intel processors) where this is 5385 profitable. 5386 * UndefinedBehaviorSanitizer gained a few new sanitization options: 5387 + -fsanitize=float-divide-by-zero: detect floating-point 5388 division by zero; 5389 + -fsanitize=float-cast-overflow: check that the result of 5390 floating-point type to integer conversions do not overflow; 5391 + -fsanitize=bounds: enable instrumentation of array bounds and 5392 detect out-of-bounds accesses; 5393 + -fsanitize=alignment: enable alignment checking, detect 5394 various misaligned objects; 5395 + -fsanitize=object-size: enable object size checking, detect 5396 various out-of-bounds accesses. 5397 + -fsanitize=vptr: enable checking of C++ member function calls, 5398 member accesses and some conversions between pointers to base 5399 and derived classes, detect if the referenced object does not 5400 have the correct dynamic type. 5401 * Pointer Bounds Checker, a bounds violation detector, has been added 5402 and can be enabled via -fcheck-pointer-bounds. Memory accesses are 5403 instrumented with run-time checks of used pointers against their 5404 bounds to detect pointer bounds violations (overflows). The Pointer 5405 Bounds Checker is available on x86/x86-64 GNU/Linux targets with a 5406 new ISA extension Intel MPX support. See the Pointer Bounds Checker 5407 [4]Wiki page for more details. 5408 5409 New Languages and Language specific improvements 5410 5411 * [5]OpenMP 4.0 specification offloading features are now supported 5412 by the C, C++, and Fortran compilers. Generic changes: 5413 + Infrastructure (suitable for any vendor). 5414 + Testsuite which covers offloading from the [6]OpenMP 4.0 5415 Examples document. 5416 Specific for upcoming Intel Xeon Phi products: 5417 + Run-time library. 5418 + Card emulator. 5419 * GCC 5 includes a preliminary implementation of the OpenACC 2.0a 5420 specification. OpenACC is intended for programming accelerator 5421 devices such as GPUs. See [7]the OpenACC wiki page for more 5422 information. 5423 5424 C family 5425 5426 * The default setting of the -fdiagnostics-color= command-line option 5427 is now [8]configurable when building GCC using configuration option 5428 --with-diagnostics-color=. The possible values are: never, always, 5429 auto and auto-if-env. The new default auto uses color only when the 5430 standard error is a terminal. The default in GCC 4.9 was 5431 auto-if-env, which is equivalent to auto if there is a non-empty 5432 GCC_COLORS environment variable, and never otherwise. As in GCC 5433 4.9, an empty GCC_COLORS variable in the environment will always 5434 disable colors, no matter what the default is or what command-line 5435 options are used. 5436 * A new command-line option -Wswitch-bool has been added for the C 5437 and C++ compilers, which warns whenever a switch statement has an 5438 index of boolean type. 5439 * A new command-line option -Wlogical-not-parentheses has been added 5440 for the C and C++ compilers, which warns about "logical not" used 5441 on the left hand side operand of a comparison. 5442 * A new command-line option -Wsizeof-array-argument has been added 5443 for the C and C++ compilers, which warns when the sizeof operator 5444 is applied to a parameter that has been declared as an array in a 5445 function definition. 5446 * A new command-line option -Wbool-compare has been added for the C 5447 and C++ compilers, which warns about boolean expressions compared 5448 with an integer value different from true/false. 5449 * Full support for Cilk Plus has been added to the GCC compiler. Cilk 5450 Plus is an extension to the C and C++ languages to support data and 5451 task parallelism. 5452 * A new attribute no_reorder prevents reordering of selected symbols 5453 against other such symbols or inline assembler. This enables to 5454 link-time optimize the Linux kernel without having to resort to 5455 -fno-toplevel-reorder that disables several optimizations. 5456 * New preprocessor constructs, __has_include and __has_include_next, 5457 to test the availability of headers have been added. 5458 This demonstrates a way to include the header <optional> only if it 5459 is available: 5460 5461 #ifdef __has_include 5462 # if __has_include(<optional>) 5463 # include <optional> 5464 # define have_optional 1 5465 # elif __has_include(<experimental/optional>) 5466 # include <experimental/optional> 5467 # define have_optional 1 5468 # define experimental_optional 5469 # else 5470 # define have_optional 0 5471 # endif 5472 #endif 5473 5474 The header search paths for __has_include and __has_include_next 5475 are equivalent to those of the standard directive #include and the 5476 extension #include_next respectively. 5477 * A new built-in function-like macro to determine the existence of an 5478 attribute, __has_attribute, has been added. The equivalent built-in 5479 macro __has_cpp_attribute was added to C++ to support 5480 [9]Feature-testing recommendations for C++. The macro 5481 __has_attribute is added to all C-like languages as an extension: 5482 5483 int 5484 #ifdef __has_attribute 5485 # if __has_attribute(__noinline__) 5486 __attribute__((__noinline__)) 5487 # endif 5488 #endif 5489 foo(int x); 5490 5491 If an attribute exists, a nonzero constant integer is returned. For 5492 standardized C++ attributes a date is returned, otherwise the 5493 constant returned is 1. Both __has_attribute and 5494 __has_cpp_attribute will add underscores to an attribute name if 5495 necessary to resolve the name. For C++11 and onwards the attribute 5496 may be scoped. 5497 * A new set of built-in functions for arithmetics with overflow 5498 checking has been added: __builtin_add_overflow, 5499 __builtin_sub_overflow and __builtin_mul_overflow and for 5500 compatibility with clang also other variants. These builtins have 5501 two integral arguments (which don't need to have the same type), 5502 the arguments are extended to infinite precision signed type, +, - 5503 or * is performed on those, and the result is stored in an integer 5504 variable pointed to by the last argument. If the stored value is 5505 equal to the infinite precision result, the built-in functions 5506 return false, otherwise true. The type of the integer variable that 5507 will hold the result can be different from the types of the first 5508 two arguments. The following snippet demonstrates how this can be 5509 used in computing the size for the calloc function: 5510 5511 void * 5512 calloc (size_t x, size_t y) 5513 { 5514 size_t sz; 5515 if (__builtin_mul_overflow (x, y, &sz)) 5516 return NULL; 5517 void *ret = malloc (sz); 5518 if (ret) memset (res, 0, sz); 5519 return ret; 5520 } 5521 5522 On e.g. i?86 or x86-64 the above will result in a mul instruction 5523 followed by a jump on overflow. 5524 * The option -fextended-identifiers is now enabled by default for 5525 C++, and for C99 and later C versions. Various bugs in the 5526 implementation of extended identifiers have been fixed. 5527 5528 C 5529 5530 * The default mode has been changed to -std=gnu11. 5531 * A new command-line option -Wc90-c99-compat has been added to warn 5532 about features not present in ISO C90, but present in ISO C99. 5533 * A new command-line option -Wc99-c11-compat has been added to warn 5534 about features not present in ISO C99, but present in ISO C11. 5535 * It is possible to disable warnings about conversions between 5536 pointers that have incompatible types via a new warning option 5537 -Wno-incompatible-pointer-types; warnings about implicit 5538 incompatible integer to pointer and pointer to integer conversions 5539 via a new warning option -Wno-int-conversion; and warnings about 5540 qualifiers on pointers being discarded via a new warning option 5541 -Wno-discarded-qualifiers. 5542 * To allow proper use of const qualifiers with multidimensional 5543 arrays, GCC will not warn about incompatible pointer types anymore 5544 for conversions between pointers to arrays with and without const 5545 qualifier (except when using -pedantic). Instead, a new warning is 5546 emitted only if the const qualifier is lost. This can be controlled 5547 with a new warning option -Wno-discarded-array-qualifiers. 5548 * The C front end now generates more precise caret diagnostics. 5549 * The -pg command-line option now only affects the current file in an 5550 LTO build. 5551 5552 C++ 5553 5554 * G++ now supports [10]C++14 variable templates. 5555 * -Wnon-virtual-dtor doesn't warn anymore for final classes. 5556 * Excessive template instantiation depth is now a fatal error. This 5557 prevents excessive diagnostics that usually do not help to identify 5558 the problem. 5559 * G++ and libstdc++ now implement the feature-testing macros from 5560 [11]Feature-testing recommendations for C++. 5561 * G++ now allows typename in a template template parameter. 5562 5563 template<template<typename> typename X> struct D; // OK 5564 5565 * G++ now supports [12]C++14 aggregates with non-static data member 5566 initializers. 5567 5568 struct A { int i, j = i; }; 5569 A a = { 42 }; // a.j is also 42 5570 5571 * G++ now supports [13]C++14 extended constexpr. 5572 5573 constexpr int f (int i) 5574 { 5575 int j = 0; 5576 for (; i > 0; --i) 5577 ++j; 5578 return j; 5579 } 5580 5581 constexpr int i = f(42); // i is 42 5582 5583 * G++ now supports the [14]C++14 sized deallocation functions. 5584 5585 void operator delete (void *, std::size_t) noexcept; 5586 void operator delete[] (void *, std::size_t) noexcept; 5587 5588 * A new One Definition Rule violation warning (controlled by -Wodr) 5589 detects mismatches in type definitions and virtual table contents 5590 during link-time optimization. 5591 * New warnings -Wsuggest-final-types and -Wsuggest-final-methods help 5592 developers to annotate programs with final specifiers (or anonymous 5593 namespaces) to improve code generation. These warnings can be used 5594 at compile time, but they are more useful in combination with 5595 link-time optimization. 5596 * G++ no longer supports [15]N3639 variable length arrays, as they 5597 were removed from the C++14 working paper prior to ratification. 5598 GNU VLAs are still supported, so VLA support is now the same in 5599 C++14 mode as in C++98 and C++11 modes. 5600 * G++ now allows passing a non-trivially-copyable class via C 5601 varargs, which is conditionally-supported with 5602 implementation-defined semantics in the standard. This uses the 5603 same calling convention as a normal value parameter. 5604 * G++ now defaults to -fabi-version=9 and -fabi-compat-version=2. So 5605 various mangling bugs are fixed, but G++ will still emit aliases 5606 with the old, wrong mangling where feasible. -Wabi=2 will warn 5607 about differences between ABI version 2 and the current setting. 5608 * G++ 5.2 fixes the alignment of std::nullptr_t. Most code is likely 5609 to be unaffected, but -Wabi=8 will warn about a non-static data 5610 member with type std::nullptr_t which changes position due to this 5611 change. 5612 5613 Runtime Library (libstdc++) 5614 5615 * A [16]Dual ABI is provided by the library. A new ABI is enabled by 5616 default. The old ABI is still supported and can be used by defining 5617 the macro _GLIBCXX_USE_CXX11_ABI to 0 before including any C++ 5618 standard library headers. 5619 * A new implementation of std::string is enabled by default, using 5620 the small string optimization instead of copy-on-write reference 5621 counting. 5622 * A new implementation of std::list is enabled by default, with an 5623 O(1) size() function; 5624 * [17]Full support for C++11, including the following new features: 5625 + std::deque and std::vector<bool> meet the allocator-aware 5626 container requirements; 5627 + movable and swappable iostream classes; 5628 + support for std::align and std::aligned_union; 5629 + type traits std::is_trivially_copyable, 5630 std::is_trivially_constructible, std::is_trivially_assignable 5631 etc.; 5632 + I/O manipulators std::put_time, std::get_time, std::hexfloat 5633 and std::defaultfloat; 5634 + generic locale-aware std::isblank; 5635 + locale facets for Unicode conversion; 5636 + atomic operations for std::shared_ptr; 5637 + std::notify_all_at_thread_exit() and functions for making 5638 futures ready at thread exit. 5639 * Support for the C++11 hexfloat manipulator changes how the num_put 5640 facet formats floating point types when 5641 ios_base::fixed|ios_base::scientific is set in a stream's fmtflags. 5642 This change affects all language modes, even though the C++98 5643 standard gave no special meaning to that combination of flags. To 5644 prevent the use of hexadecimal notation for floating point types 5645 use str.unsetf(std::ios_base::floatfield) to clear the relevant 5646 bits in str.flags(). 5647 * [18]Full experimental support for C++14, including the following 5648 new features: 5649 + std::is_final type trait; 5650 + heterogeneous comparison lookup in associative containers. 5651 + global functions cbegin, cend, rbegin, rend, crbegin, and 5652 crend for range access to containers, arrays and initializer 5653 lists. 5654 * [19]Improved experimental support for the Library Fundamentals TS, 5655 including: 5656 + class std::experimental::any; 5657 + function template std::experimental::apply; 5658 + function template std::experimental::sample; 5659 + function template std::experimental::search and related 5660 searcher types; 5661 + variable templates for type traits; 5662 + function template std::experimental::not_fn. 5663 * New random number distributions logistic_distribution and 5664 uniform_on_sphere_distribution as extensions. 5665 * [20]GDB Xmethods for containers and std::unique_ptr. 5666 5667 Fortran 5668 5669 * Compatibility notice: 5670 + The version of the module files (.mod) has been incremented. 5671 + For free-form source files [21]-Werror=line-truncation is now 5672 enabled by default. Note that comments exceeding the line 5673 length are not diagnosed. (For fixed-form source code, the 5674 same warning is available but turned off by default, such that 5675 excess characters are ignored. -ffree-line-length-n and 5676 -ffixed-line-length-n can be used to modify the default line 5677 lengths of 132 and 72 columns, respectively.) 5678 + The -Wtabs option is now more sensible: with -Wtabs the 5679 compiler warns if it encounters tabs and with -Wno-tabs this 5680 warning is turned off. Before, -Wno-tabs warned and -Wtabs 5681 disabled the warning. As before, this warning is also enabled 5682 by -Wall, -pedantic and the f95, f2003, f2008 and f2008ts 5683 options of -std=. 5684 * Incomplete support for colorizing diagnostics emitted by gfortran 5685 has been added. The option [22]-fdiagnostics-color controls when 5686 color is used in diagnostics. The default value of this option can 5687 be [23]configured when building GCC. The GCC_COLORS environment 5688 variable can be used to customize the colors or disable coloring 5689 completely. Sample diagnostics output: 5690 $ gfortran -fdiagnostics-color=always -Wuse-without-only test.f90 5691 test.f90:6:1: 5692 5693 0 continue 5694 1 5695 Error: Zero is not a valid statement label at (1) 5696 test.f90:9:6: 5697 5698 USE foo 5699 1 5700 Warning: USE statement at (1) has no ONLY qualifier [-Wuse-without-only] 5701 5702 * The -Wuse-without-only option has been added to warn when a USE 5703 statement has no ONLY qualifier and thus implicitly imports all 5704 public entities of the used module. 5705 * Formatted READ and WRITE statements now work correctly in 5706 locale-aware programs. For more information and potential caveats, 5707 see [24]Section 5.3 Thread-safety of the runtime library in the 5708 manual. 5709 * [25]Fortran 2003: 5710 + The intrinsic IEEE modules (IEEE_FEATURES, IEEE_EXCEPTIONS and 5711 IEEE_ARITHMETIC) are now supported. 5712 * [26]Fortran 2008: 5713 + [27]Coarrays: Full experimental support of Fortran 2008's 5714 coarrays with -fcoarray=lib except for allocatable/pointer 5715 components of derived-type coarrays. GCC currently only ships 5716 with a single-image library (libcaf_single), but multi-image 5717 support based on MPI and GASNet is provided by the libraries 5718 of the [28]OpenCoarrays project. 5719 * TS18508 Additional Parallel Features in Fortran: 5720 + Support for the collective intrinsic subroutines CO_MAX, 5721 CO_MIN, CO_SUM, CO_BROADCAST and CO_REDUCE has been added, 5722 including -fcoarray=lib support. 5723 + Support for the new atomic intrinsics has been added, 5724 including -fcoarray=lib support. 5725 * Fortran 2015: 5726 + Support for IMPLICIT NONE (external, type). 5727 + ERROR STOP is now permitted in pure procedures. 5728 5729 Go 5730 5731 * GCC 5 provides a complete implementation of the Go 1.4.2 release. 5732 * Building GCC 5 with Go enabled will install two new programs: 5733 [29]go and [30]gofmt. 5734 5735 libgccjit 5736 5737 New in GCC 5 is the ability to build GCC as a shared library for 5738 embedding in other processes (such as interpreters), suitable for 5739 Just-In-Time compilation to machine code. 5740 5741 The shared library has a [31]C API and a [32]C++ wrapper API providing 5742 some "syntactic sugar". There are also bindings available from 3rd 5743 parties for [33]Python and for [34]D. 5744 5745 For example, this library can be used by interpreters for [35]compiling 5746 functions from bytecode to machine code. 5747 5748 The library can also be used for ahead-of-time compilation, enabling 5749 GCC to be plugged into a pre-existing front end. An example of using 5750 this to build a compiler for an esoteric language we'll refer to as 5751 "brainf" can be seen [36]here. 5752 5753 libgccjit is licensed under the GPLv3 (or at your option, any later 5754 version) 5755 5756 It should be regarded as experimental at this time. 5757 5758 New Targets and Target Specific Improvements 5759 5760 Reporting stack usage 5761 5762 * The BFIN, FT32, H8300, IQ2000 and M32C targets now support the 5763 -fstack-usage option. 5764 5765 AArch64 5766 5767 * Code generation for the ARM Cortex-A57 processor has been improved. 5768 A more accurate instruction scheduling model for the processor is 5769 now used, and a number of compiler tuning parameters have been set 5770 to offer increased performance when compiling with -mcpu=cortex-a57 5771 or -mtune=cortex-a57. 5772 * A workaround for the ARM Cortex-A53 erratum 835769 has been added 5773 and can be enabled by giving the -mfix-cortex-a53-835769 option. 5774 Alternatively it can be enabled by default by configuring GCC with 5775 the --enable-fix-cortex-a53-835769 option. 5776 * The optional cryptographic extensions to the ARMv8-A architecture 5777 are no longer enabled by default when specifying the 5778 -mcpu=cortex-a53, -mcpu=cortex-a57 or -mcpu=cortex-a57.cortex-a53 5779 options. To enable these extensions add +crypto to the value of 5780 -mcpu or -march e.g. -mcpu=cortex-a53+crypto. 5781 * Support has been added for the following processors (GCC 5782 identifiers in parentheses): ARM Cortex-A72 (cortex-a72) and 5783 initial support for its big.LITTLE combination with the ARM 5784 Cortex-A53 (cortex-a72.cortex-a53), Cavium ThunderX (thunderx), 5785 Applied Micro X-Gene 1 (xgene1), and Samsung Exynos M1 (exynos-m1). 5786 The GCC identifiers can be used as arguments to the -mcpu or -mtune 5787 options, for example: -mcpu=xgene1 or -mtune=cortex-a72.cortex-a53. 5788 Using -mcpu=cortex-a72 requires a version of GNU binutils that has 5789 support for the Cortex-A72. 5790 * The transitional options -mlra and -mno-lra have been removed. The 5791 AArch64 backend now uses the local register allocator (LRA) only. 5792 5793 ARM 5794 5795 * Thumb-1 assembly code is now generated in unified syntax. The new 5796 option -masm-syntax-unified specifies whether inline assembly code 5797 is using unified syntax. By default the option is off which means 5798 non-unified syntax is used. However this is subject to change in 5799 future releases. Eventually the non-unified syntax will be 5800 deprecated. 5801 * It is now a configure-time error to use the --with-cpu configure 5802 option with either of --with-tune or --with-arch. 5803 * Code generation for the ARM Cortex-A57 processor has been improved. 5804 A more accurate instruction scheduling model for the processor is 5805 now used, and a number of compiler tuning parameters have been set 5806 to offer increased performance when compiling with -mcpu=cortex-a57 5807 or -mtune=cortex-a57. 5808 * Support has been added for the following processors (GCC 5809 identifiers in parentheses): ARM Cortex-A17 (cortex-a17) and 5810 initial support for its big.LITTLE combination with the ARM 5811 Cortex-A7 (cortex-a17.cortex-a7), ARM Cortex-A72 (cortex-a72) and 5812 initial support for its big.LITTLE combination with the ARM 5813 Cortex-A53 (cortex-a72.cortex-a53), ARM Cortex-M7 (cortex-m7), 5814 Applied Micro X-Gene 1 (xgene1), and Samsung Exynos M1 (exynos-m1). 5815 The GCC identifiers can be used as arguments to the -mcpu or -mtune 5816 options, for example: -mcpu=xgene1 or -mtune=cortex-a72.cortex-a53. 5817 Using -mcpu=cortex-a72 requires a version of GNU binutils that has 5818 support for the Cortex-A72. 5819 * The deprecated option -mwords-little-endian has been removed. 5820 * The options -mapcs, -mapcs-frame, -mtpcs-frame and 5821 -mtpcs-leaf-frame which are only applicable to the old ABI have 5822 been deprecated. 5823 * The transitional options -mlra and -mno-lra have been removed. The 5824 ARM backend now uses the local register allocator (LRA) only. 5825 5826 AVR 5827 5828 * The compiler no more supports individual devices like ATmega8. 5829 Specifying, say, -mmcu=atmega8 triggers the usage of the 5830 device-specific [37]spec file specs-atmega8 which is part of the 5831 installation and describes options for the sub-processes like 5832 compiler proper, assembler and linker. You can add support for a 5833 new device -mmcu=mydevice as follows: 5834 1. In an empty directory /someplace, create a new directory 5835 device-specs. 5836 2. Copy a device spec file from the installed device-specs 5837 folder, follow the comments in that file and then save it as 5838 /someplace/device-specs/specs-mydevice. 5839 3. Add -B /someplace -mmcu=mydevice to the compiler's 5840 command-line options. Notice that /someplace must specify an 5841 absolute path and that mydevice must not start with "avr". 5842 4. Provided you have a device-specific library libmydevice.a 5843 available, you can put it at /someplace, dito for a 5844 device-specific startup file crtmydevice.o. 5845 The contents of the device spec files depend on the compiler's 5846 configuration, in particular on --with-avrlibc=no and whether or 5847 not it is configured for RTEMS. 5848 * A new command-line option -nodevicelib has been added. It prevents 5849 the compiler from linking against AVR-LibC's device-specific 5850 library libdevice.a. 5851 * The following three command-line options have been added: 5852 5853 -mrmw 5854 Set if the device supports the read-modify-write 5855 instructions LAC, LAS, LAT and XCH. 5856 5857 -mn-flash=size 5858 Specify the flash size of the device in units of 64 KiB, 5859 rounded up to the next integer as needed. This option 5860 affects the availability of the [38]AVR address-spaces. 5861 5862 -mskip-bug 5863 Set if the device is affected by the respective silicon 5864 bug. 5865 5866 In general, you don't need to set these options by hand. The new 5867 device-specific spec file will set them as needed. 5868 5869 IA-32/x86-64 5870 5871 * New ISA extensions support AVX-512{BW,DQ,VL,IFMA,VBMI} of Intel's 5872 CPU codenamed Skylake Server was added to GCC. That includes inline 5873 assembly support, new intrinsics, and basic autovectorization. 5874 These new AVX-512 extensions are available via the following GCC 5875 switches: AVX-512 Vector Length EVEX feature: -mavx512vl, AVX-512 5876 Byte and Word instructions: -mavx512bw, AVX-512 Dword and Qword 5877 instructions: -mavx512dq, AVX-512 FMA-52 instructions: -mavx512ifma 5878 and for AVX-512 Vector Bit Manipulation Instructions: -mavx512vbmi. 5879 * New ISA extensions support Intel MPX was added to GCC. This new 5880 extension is available via the -mmpx compiler switch. Intel MPX is 5881 a set of processor features which, with compiler, run-time library 5882 and OS support, brings increased robustness to software by run-time 5883 checking pointer references against their bounds. In GCC Intel MPX 5884 is supported by Pointer Bounds Checker and libmpx run-time 5885 libraries. 5886 * The new -mrecord-mcount option for -pg generates a Linux kernel 5887 style table of pointers to mcount or __fentry__ calls at the 5888 beginning of functions. The new -mnop-mcount option in addition 5889 also generates nops in place of the __fentry__ or mcount call, so 5890 that a call per function can be later patched in. This can be used 5891 for low overhead tracing or hot code patching. 5892 * The new -malign-data option controls how GCC aligns variables. 5893 -malign-data=compat uses increased alignment compatible with GCC 5894 4.8 and earlier, -malign-data=abi uses alignment as specified by 5895 the psABI, and -malign-data=cacheline uses increased alignment to 5896 match the cache line size. -malign-data=compat is the default. 5897 * The new -mskip-rax-setup option skips setting up the RAX register 5898 when SSE is disabled and there are no variable arguments passed in 5899 vector registers. This can be used to optimize the Linux kernel. 5900 5901 MIPS 5902 5903 * MIPS Releases 3 and 5 are now directly supported. Use the 5904 command-line options -mips32r3, -mips64r3, -mips32r5 and -mips64r5 5905 to enable code-generation for these processors. 5906 * The Imagination P5600 processor is now supported using the 5907 -march=p5600 command-line option. 5908 * The Cavium Octeon3 processor is now supported using the 5909 -march=octeon3 command-line option. 5910 * MIPS Release 6 is now supported using the -mips32r6 and -mips64r6 5911 command-line options. 5912 * The o32 ABI has been modified and extended. The o32 64-bit 5913 floating-point register support is now obsolete and has been 5914 removed. It has been replaced by three ABI extensions FPXX, FP64A, 5915 and FP64. The meaning of the -mfp64 command-line option has 5916 changed. It is now used to enable the FP64A and FP64 ABI 5917 extensions. 5918 + The FPXX extension requires that code generated to access 5919 double-precision values use even-numbered registers. Code that 5920 adheres to this extension is link-compatible with all other 5921 o32 double-precision ABI variants and will execute correctly 5922 in all hardware FPU modes. The command-line options -mabi=32 5923 -mfpxx can be used to enable this extension. MIPS II is the 5924 minimum processor required. 5925 + The o32 FP64A extension requires that floating-point registers 5926 be 64-bit and odd-numbered single-precision registers are not 5927 allowed. Code that adheres to the o32 FP64A variant is 5928 link-compatible with all other o32 double-precision ABI 5929 variants. The command-line options -mabi=32 -mfp64 5930 -mno-odd-spreg can be used to enable this extension. MIPS32R2 5931 is the minimum processor required. 5932 + The o32 FP64 extension also requires that floating-point 5933 registers be 64-bit, but permits the use of single-precision 5934 registers. Code that adheres to the o32 FP64 variant is 5935 link-compatible with o32 FPXX and o32 FP64A variants only, 5936 i.e. it is not compatible with the original o32 5937 double-precision ABI. The command-line options -mabi=32 -mfp64 5938 -modd-spreg can be used to enable this extension. MIPS32R2 is 5939 the minimum processor required. 5940 The new ABI variants can be enabled by default using the configure 5941 time options --with-fp-32=[32|xx|64] and --with(out)-odd-sp-reg-32. 5942 It is strongly recommended that all vendors begin to set o32 FPXX 5943 as the default ABI. This will be required to run the generated code 5944 on MIPSR5 cores in conjunction with future MIPS SIMD (MSA) code and 5945 MIPSR6 cores. 5946 * GCC will now pass all floating-point options to the assembler if 5947 GNU binutils 2.25 is used. As a result, any inline assembly code 5948 that uses hard-float instructions should be amended to include a 5949 .set directive to override the global assembler options when 5950 compiling for soft-float targets. 5951 5952 NDS32 5953 5954 * The variadic function ABI implementation is now compatible with 5955 past Andes toolchains where the caller uses registers to pass 5956 arguments and the callee is in charge of pushing them on stack. 5957 * The options -mforce-fp-as-gp, -mforbid-fp-as-gp, and -mex9 have 5958 been removed since they are not yet available in the nds32 port of 5959 GNU binutils. 5960 * A new option -mcmodel=[small|medium|large] supports varied code 5961 models on code generation. The -mgp-direct option became 5962 meaningless and can be discarded. 5963 5964 RX 5965 5966 * A new command line option -mno-allow-string-insns can be used to 5967 disable the generation of the SCMPU, SMOVU, SMOVB, SMOVF, SUNTIL, 5968 SWHILE and RMPA instructions. An erratum released by Renesas shows 5969 that it is unsafe to use these instructions on addresses within the 5970 I/O space of the processor. The new option can be used when the 5971 programmer is concerned that the I/O space might be accessed. The 5972 default is still to enable these instructions. 5973 5974 SH 5975 5976 * The compiler will now pass the appropriate --isa= option to the 5977 assembler. 5978 * The default handling for the GBR has been changed from call 5979 clobbered to call preserved. The old behavior can be reinstated by 5980 specifying the option -fcall-used-gbr. 5981 * Support for the SH4A fpchg instruction has been added which will be 5982 utilized when switching between single and double precision FPU 5983 modes. 5984 * The compiler no longer uses the __fpscr_values array for switching 5985 between single and double FPU precision modes on non-SH4A targets. 5986 Instead mode switching will now be performed by storing, modifying 5987 and reloading the FPSCR, so that other FPSCR bits are preserved 5988 across mode switches. The __fpscr_values array that is defined in 5989 libgcc is still present for backwards compatibility, but it will 5990 not be referenced by compiler generated code anymore. 5991 * New builtin functions __builtin_sh_get_fpscr and 5992 __builtin_sh_set_fpscr have been added. The __builtin_sh_set_fpscr 5993 function will mask the specified bits in such a way that the SZ, PR 5994 and FR mode bits will be preserved, while changing the other bits. 5995 These new functions do not reference the __fpscr_values array. The 5996 old functions __set_fpscr and __get_fpscr in libgcc which access 5997 the __fpscr_values array are still present for backwards 5998 compatibility, but their usage is highly discouraged. 5999 * Some improvements to code generated for __atomic built-in 6000 functions. 6001 * When compiling for SH2E the compiler will no longer force the usage 6002 of delay slots for conditional branch instructions bt and bf. The 6003 old behavior can be reinstated (e.g. to work around a hardware bug 6004 in the original SH7055) by specifying the new option 6005 -mcbranch-force-delay-slot. 6006 6007 Operating Systems 6008 6009 AIX 6010 6011 * GCC now supports stabs debugging continuation lines to allow long 6012 stabs debug information without overflow that generates AIX linker 6013 errors. 6014 6015 DragonFly BSD 6016 6017 * GCC now supports the DragonFly BSD operating system. 6018 6019 FreeBSD 6020 6021 * GCC now supports the FreeBSD operating system for the arm port 6022 through the arm*-*-freebsd* target triplets. 6023 6024 VxWorks MILS 6025 6026 * GCC now supports the MILS (Multiple Independent Levels of Security) 6027 variant of WindRiver's VxWorks operating system for PowerPC 6028 targets. 6029 6030 Other significant improvements 6031 6032 * The gcc-ar, gcc-nm, gcc-ranlib wrappers now understand a -B option 6033 to set the compiler to use. 6034 6035 * When the new command-line option -freport-bug is used, GCC 6036 automatically generates a developer-friendly reproducer whenever an 6037 internal compiler error is encountered. 6038 6039 GCC 5.2 6040 6041 This is the [39]list of problem reports (PRs) from GCC's bug tracking 6042 system that are known to be fixed in the 5.2 release. This list might 6043 not be complete (that is, it is possible that some PRs that have been 6044 fixed are not listed here). 6045 6046 Target Specific Changes 6047 6048 IA-32/x86-64 6049 6050 * Support for new AMD instructions monitorx and mwaitx has been 6051 added. This includes new intrinsic and built-in support. It is 6052 enabled through option -mmwaitx. The instructions monitorx and 6053 mwaitx implement the same functionality as the old monitor and 6054 mwait instructions. In addition, mwaitx adds a configurable timer. 6055 The timer value is received as third argument and stored in 6056 register %ebx. 6057 6058 S/390, System z, IBM z Systems 6059 6060 * Support for the IBM z13 processor has been added. When using the 6061 -march=z13 option, the compiler will generate code making use of 6062 the new instructions and registers introduced with the vector 6063 extension facility. The -mtune=z13 option enables z13 specific 6064 instruction scheduling without making use of new instructions. 6065 Compiling code with -march=z13 reduces the default alignment of 6066 vector types bigger than 8 bytes to 8. This is an ABI change and 6067 care must be taken when linking modules compiled with different 6068 arch levels which interchange variables containing vector type 6069 values. For newly compiled code the GNU linker will emit a warning. 6070 * The -mzvector option enables a C/C++ language extension. This 6071 extension provides a new keyword vector which can be used to define 6072 vector type variables. (Note: This is not available when enforcing 6073 strict standard compliance e.g. with -std=c99. Either enable GNU 6074 extensions with e.g. -std=gnu99 or use __vector instead of vector.) 6075 Additionally a set of overloaded builtins is provided which is 6076 partially compatible to the PowerPC Altivec builtins. In order to 6077 make use of these builtins the vecintrin.h header file needs to be 6078 included. 6079 6080 GCC 5.3 6081 6082 This is the [40]list of problem reports (PRs) from GCC's bug tracking 6083 system that are known to be fixed in the 5.3 release. This list might 6084 not be complete (that is, it is possible that some PRs that have been 6085 fixed are not listed here). 6086 6087 Target Specific Changes 6088 6089 IA-32/x86-64 6090 6091 * GCC now supports the Intel CPU named Skylake with AVX-512 6092 extensions through -march=skylake-avx512. The switch enables the 6093 following ISA extensions: AVX-512F, AVX512VL, AVX-512CD, AVX-512BW, 6094 AVX-512DQ. 6095 6096 S/390, System z, IBM z Systems 6097 6098 * With this version of GCC IBM z Systems support has been added to 6099 the GO runtime environment. GCC 5.3 has proven to be able to 6100 compile larger GO applications on IBM z Systems. 6101 6102 GCC 5.4 6103 6104 This is the [41]list of problem reports (PRs) from GCC's bug tracking 6105 system that are known to be fixed in the 5.4 release. This list might 6106 not be complete (that is, it is possible that some PRs that have been 6107 fixed are not listed here). 6108 6109 GCC 5.5 6110 6111 This is the [42]list of problem reports (PRs) from GCC's bug tracking 6112 system that are known to be fixed in the 5.5 release. This list might 6113 not be complete (that is, it is possible that some PRs that have been 6114 fixed are not listed here). 6115 6116 Target Specific Changes 6117 6118 IA-32/x86-64 6119 6120 * Support for the [43]deprecated pcommit instruction has been 6121 removed. 6122 6123 6124 For questions related to the use of GCC, please consult these web 6125 pages and the [44]GCC manuals. If that fails, the 6126 [45]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 6127 web pages and the development of GCC are welcome on our developer 6128 list at [46]gcc (a] gcc.gnu.org. All of [47]our lists have public 6129 archives. 6130 6131 Copyright (C) [48]Free Software Foundation, Inc. Verbatim copying and 6132 distribution of this entire article is permitted in any medium, 6133 provided this notice is preserved. 6134 6135 These pages are [49]maintained by the GCC team. Last modified 6136 2023-02-20. 6137 6138 References 6139 6140 1. http://gcc.gnu.org/gcc-5/changes.html#libstdcxx 6141 2. https://gcc.gnu.org/onlinedocs/gcc/Spec-Files.html 6142 3. https://savannah.nongnu.org/bugs/?44574 6143 4. https://gcc.gnu.org/wiki/Intel%20MPX%20support%20in%20the%20GCC%20compiler 6144 5. https://www.openmp.org/wp-content/uploads/OpenMP4.0.0.pdf 6145 6. https://www.openmp.org/wp-content/uploads/OpenMP4.0.0.Examples.pdf 6146 7. https://gcc.gnu.org/wiki/OpenACC 6147 8. https://gcc.gnu.org/install/configure.html 6148 9. https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations 6149 10. http://gcc.gnu.org/projects/cxx1y.html 6150 11. https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations 6151 12. http://gcc.gnu.org/projects/cxx1y.html 6152 13. http://gcc.gnu.org/projects/cxx1y.html 6153 14. http://gcc.gnu.org/projects/cxx1y.html 6154 15. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3639.html 6155 16. http://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html 6156 17. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/libstdc++/manual/manual/status.html#status.iso.2011 6157 18. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/libstdc++/manual/manual/status.html#status.iso.2014 6158 19. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/libstdc++/manual/manual/status.html#status.iso.2014 6159 20. https://sourceware.org/gdb/current/onlinedocs/gdb#Xmethods-In-Python 6160 21. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/gfortran/Error-and-Warning-Options.html 6161 22. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/gcc/Language-Independent-Options.html 6162 23. https://gcc.gnu.org/install/configure.html 6163 24. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/gfortran/Thread-safety-of-the-runtime-library.html 6164 25. https://gcc.gnu.org/wiki/Fortran2003Status 6165 26. https://gcc.gnu.org/wiki/Fortran2008Status 6166 27. https://gcc.gnu.org/wiki/Coarray 6167 28. http://www.opencoarrays.org/ 6168 29. https://pkg.go.dev/cmd/go 6169 30. https://pkg.go.dev/cmd/gofmt 6170 31. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/jit/intro/index.html 6171 32. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/jit/cp/index.html 6172 33. https://github.com/davidmalcolm/pygccjit 6173 34. https://github.com/ibuclaw/gccjitd 6174 35. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/jit/intro/tutorial04.html 6175 36. https://gcc.gnu.org/onlinedocs/gcc-5.1.0/jit/intro/tutorial05.html 6176 37. https://gcc.gnu.org/onlinedocs/gcc/Spec-Files.html 6177 38. https://gcc.gnu.org/onlinedocs/gcc/Named-Address-Spaces.html 6178 39. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=5.2 6179 40. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=5.3 6180 41. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=5.4 6181 42. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=5.5 6182 43. https://www.intel.com/content/www/us/en/developer/articles/technical/deprecate-pcommit-instruction.html 6183 44. https://gcc.gnu.org/onlinedocs/ 6184 45. mailto:gcc-help (a] gcc.gnu.org 6185 46. mailto:gcc (a] gcc.gnu.org 6186 47. https://gcc.gnu.org/lists.html 6187 48. https://www.fsf.org/ 6188 49. https://gcc.gnu.org/about.html 6189 ====================================================================== 6190 http://gcc.gnu.org/gcc-4.9/index.html 6191 6192 GCC 4.9 Release Series 6193 6194 (This release series is no longer supported.) 6195 6196 Aug 3, 2016 6197 6198 The [1]GNU project and the GCC developers are pleased to announce the 6199 release of GCC 4.9.4. 6200 6201 This release is a bug-fix release, containing fixes for regressions in 6202 GCC 4.9.3 relative to previous releases of GCC. 6203 6204 Release History 6205 6206 GCC 4.9.4 6207 Aug 3, 2016 ([2]changes, [3]documentation) 6208 6209 GCC 4.9.3 6210 June 26, 2015 ([4]changes, [5]documentation) 6211 6212 GCC 4.9.2 6213 October 30, 2014 ([6]changes, [7]documentation) 6214 6215 GCC 4.9.1 6216 July 16, 2014 ([8]changes, [9]documentation) 6217 6218 GCC 4.9.0 6219 April 22, 2014 ([10]changes, [11]documentation) 6220 6221 References and Acknowledgements 6222 6223 GCC used to stand for the GNU C Compiler, but since the compiler 6224 supports several other languages aside from C, it now stands for the 6225 GNU Compiler Collection. 6226 6227 A list of [12]successful builds is updated as new information becomes 6228 available. 6229 6230 The GCC developers would like to thank the numerous people that have 6231 contributed new features, improvements, bug fixes, and other changes as 6232 well as test results to GCC. This [13]amazing group of volunteers is 6233 what makes GCC successful. 6234 6235 For additional information about GCC please refer to the [14]GCC 6236 project web site or contact the [15]GCC development mailing list. 6237 6238 To obtain GCC please use [16]our mirror sites or [17]our version 6239 control system. 6240 6241 6242 For questions related to the use of GCC, please consult these web 6243 pages and the [18]GCC manuals. If that fails, the 6244 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 6245 web pages and the development of GCC are welcome on our developer 6246 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 6247 archives. 6248 6249 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 6250 distribution of this entire article is permitted in any medium, 6251 provided this notice is preserved. 6252 6253 These pages are [23]maintained by the GCC team. Last modified 6254 2022-10-26. 6255 6256 References 6257 6258 1. http://www.gnu.org/ 6259 2. http://gcc.gnu.org/gcc-4.9/changes.html 6260 3. http://gcc.gnu.org/onlinedocs/4.9.4/ 6261 4. http://gcc.gnu.org/gcc-4.9/changes.html 6262 5. http://gcc.gnu.org/onlinedocs/4.9.3/ 6263 6. http://gcc.gnu.org/gcc-4.9/changes.html 6264 7. http://gcc.gnu.org/onlinedocs/4.9.2/ 6265 8. http://gcc.gnu.org/gcc-4.9/changes.html 6266 9. http://gcc.gnu.org/onlinedocs/4.9.1/ 6267 10. http://gcc.gnu.org/gcc-4.9/changes.html 6268 11. https://gcc.gnu.org/onlinedocs/4.9.0/ 6269 12. http://gcc.gnu.org/gcc-4.9/buildstat.html 6270 13. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 6271 14. http://gcc.gnu.org/index.html 6272 15. mailto:gcc (a] gcc.gnu.org 6273 16. http://gcc.gnu.org/mirrors.html 6274 17. http://gcc.gnu.org/git.html 6275 18. https://gcc.gnu.org/onlinedocs/ 6276 19. mailto:gcc-help (a] gcc.gnu.org 6277 20. mailto:gcc (a] gcc.gnu.org 6278 21. https://gcc.gnu.org/lists.html 6279 22. https://www.fsf.org/ 6280 23. https://gcc.gnu.org/about.html 6281 ====================================================================== 6282 http://gcc.gnu.org/gcc-4.9/changes.html 6283 6284 GCC 4.9 Release Series 6285 Changes, New Features, and Fixes 6286 6287 Caveats 6288 6289 * The mudflap run time checker has been removed. The mudflap options 6290 remain, but do nothing. 6291 * Support for a number of older systems and recently unmaintained or 6292 untested target ports of GCC has been declared obsolete in GCC 4.9. 6293 Unless there is activity to revive them, the next release of GCC 6294 will have their sources permanently removed. 6295 The following ports for individual systems on particular 6296 architectures have been obsoleted: 6297 + Solaris 9 (*-*-solaris2.9). Details can be found in the 6298 [1]announcement. 6299 * On AArch64, the singleton vector types int64x1_t, uint64x1_t and 6300 float64x1_t exported by arm_neon.h are defined to be the same as 6301 their base types. This results in incorrect application of 6302 parameter passing rules to arguments of types int64x1_t and 6303 uint64x1_t, with respect to the AAPCS64 ABI specification. In 6304 addition, names of C++ functions with parameters of these types 6305 (including float64x1_t) are not mangled correctly. The current 6306 typedef declarations also unintentionally allow implicit casting 6307 between singleton vector types and their base types. These issues 6308 will be resolved in a near future release. See [2]PR60825 for more 6309 information. 6310 6311 More information on porting to GCC 4.9 from previous versions of GCC 6312 can be found in the [3]porting guide for this release. 6313 6314 General Optimizer Improvements 6315 6316 * AddressSanitizer, a fast memory error detector, is now available on 6317 ARM. 6318 * UndefinedBehaviorSanitizer (ubsan), a fast undefined behavior 6319 detector, has been added and can be enabled via 6320 -fsanitize=undefined. Various computations will be instrumented to 6321 detect undefined behavior at runtime. UndefinedBehaviorSanitizer is 6322 currently available for the C and C++ languages. 6323 * Link-time optimization (LTO) improvements: 6324 + Type merging was rewritten. The new implementation is 6325 significantly faster and uses less memory. 6326 + Better partitioning algorithm resulting in less streaming 6327 during link time. 6328 + Early removal of virtual methods reduces the size of object 6329 files and improves link-time memory usage and compile time. 6330 + Function bodies are now loaded on-demand and released early 6331 improving overall memory usage at link time. 6332 + C++ hidden keyed methods can now be optimized out. 6333 + When using a linker plugin, compiling with the -flto option 6334 now generates slim object files (.o) which only contain 6335 intermediate language representation for LTO. Use 6336 -ffat-lto-objects to create files which contain additionally 6337 the object code. To generate static libraries suitable for LTO 6338 processing, use gcc-ar and gcc-ranlib; to list symbols from a 6339 slim object file use gcc-nm. (This requires that ar, ranlib 6340 and nm have been compiled with plugin support.) 6341 Memory usage building Firefox with debug enabled was reduced from 6342 15GB to 3.5GB; link time from 1700 seconds to 350 seconds. 6343 * Inter-procedural optimization improvements: 6344 + New type inheritance analysis module improving 6345 devirtualization. Devirtualization now takes into account 6346 anonymous name-spaces and the C++11 final keyword. 6347 + New speculative devirtualization pass (controlled by 6348 -fdevirtualize-speculatively. 6349 + Calls that were speculatively made direct are turned back to 6350 indirect where direct call is not cheaper. 6351 + Local aliases are introduced for symbols that are known to be 6352 semantically equivalent across shared libraries improving 6353 dynamic linking times. 6354 * Feedback directed optimization improvements: 6355 + Profiling of programs using C++ inline functions is now more 6356 reliable. 6357 + New time profiling determines typical order in which functions 6358 are executed. 6359 + A new function reordering pass (controlled by 6360 -freorder-functions) significantly reduces startup time of 6361 large applications. Until binutils support is completed, it is 6362 effective only with link-time optimization. 6363 + Feedback driven indirect call removal and devirtualization now 6364 handle cross-module calls when link-time optimization is 6365 enabled. 6366 6367 New Languages and Language specific improvements 6368 6369 * Version 4.0 of the [4]OpenMP specification is now supported in the 6370 C and C++ compilers and starting with the 4.9.1 release also in the 6371 Fortran compiler. The new -fopenmp-simd option can be used to 6372 enable OpenMP's SIMD directives while ignoring other OpenMP 6373 directives. The new [5]-fsimd-cost-model= option permits to tune 6374 the vectorization cost model for loops annotated with OpenMP and 6375 Cilk Plus simd directives. -Wopenmp-simd warns when the current 6376 cost model overrides simd directives set by the user. 6377 * The -Wdate-time option has been added for the C, C++ and Fortran 6378 compilers, which warns when the __DATE__, __TIME__ or __TIMESTAMP__ 6379 macros are used. Those macros might prevent bit-wise-identical 6380 reproducible compilations. 6381 6382 Ada 6383 6384 * GNAT switched to Ada 2012 instead of Ada 2005 by default. 6385 6386 C family 6387 6388 * Support for colorizing diagnostics emitted by GCC has been added. 6389 The [6]-fdiagnostics-color=auto will enable it when outputting to 6390 terminals, -fdiagnostics-color=always unconditionally. The 6391 GCC_COLORS environment variable can be used to customize the colors 6392 or disable coloring. If GCC_COLORS variable is present in the 6393 environment, the default is -fdiagnostics-color=auto, otherwise 6394 -fdiagnostics-color=never. 6395 Sample diagnostics output: 6396 $ g++ -fdiagnostics-color=always -S -Wall test.C 6397 test.C: In function `int foo()': 6398 test.C:1:14: warning: no return statement in function returning non-void [-W 6399 return-type] 6400 int foo () { } 6401 ^ 6402 test.C:2:46: error: template instantiation depth exceeds maximum of 900 (use 6403 -ftemplate-depth= to increase the maximum) instantiating `struct X<100>' 6404 template <int N> struct X { static const int value = X<N-1>::value; }; temp 6405 late struct X<1000>; 6406 ^ 6407 test.C:2:46: recursively required from `const int X<999>::value' 6408 test.C:2:46: required from `const int X<1000>::value' 6409 test.C:2:88: required from here 6410 6411 test.C:2:46: error: incomplete type `X<100>' used in nested name specifier 6412 6413 * With the new [7]#pragma GCC ivdep, the user can assert that there 6414 are no loop-carried dependencies which would prevent concurrent 6415 execution of consecutive iterations using SIMD (single instruction 6416 multiple data) instructions. 6417 * Support for Cilk Plus has been added and can be enabled with the 6418 -fcilkplus option. Cilk Plus is an extension to the C and C++ 6419 languages to support data and task parallelism. The present 6420 implementation follows ABI version 1.2; all features but _Cilk_for 6421 have been implemented. 6422 6423 C 6424 6425 * ISO C11 atomics (the _Atomic type specifier and qualifier and the 6426 <stdatomic.h> header) are now supported. 6427 * ISO C11 generic selections (_Generic keyword) are now supported. 6428 * ISO C11 thread-local storage (_Thread_local, similar to GNU C 6429 __thread) is now supported. 6430 * ISO C11 support is now at a similar level of completeness to ISO 6431 C99 support: substantially complete modulo bugs, extended 6432 identifiers (supported except for corner cases when 6433 -fextended-identifiers is used), floating-point issues (mainly but 6434 not entirely relating to optional C99 features from Annexes F and 6435 G) and the optional Annexes K (Bounds-checking interfaces) and L 6436 (Analyzability). 6437 * A new C extension __auto_type provides a subset of the 6438 functionality of C++11 auto in GNU C. 6439 6440 C++ 6441 6442 * The G++ implementation of [8]C++1y return type deduction for normal 6443 functions has been updated to conform to [9]N3638, the proposal 6444 accepted into the working paper. Most notably, it adds 6445 decltype(auto) for getting decltype semantics rather than the 6446 template argument deduction semantics of plain auto: 6447 6448 int& f(); 6449 auto i1 = f(); // int 6450 decltype(auto) i2 = f(); // int& 6451 6452 * G++ supports [10]C++1y lambda capture initializers: 6453 6454 [x = 42]{ ... }; 6455 6456 Actually, they have been accepted since GCC 4.5, but now the 6457 compiler doesn't warn about them with -std=c++1y, and supports 6458 parenthesized and brace-enclosed initializers as well. 6459 * G++ supports [11]C++1y variable length arrays. G++ has supported 6460 GNU/C99-style VLAs for a long time, but now additionally supports 6461 initializers and lambda capture by reference. In C++1y mode G++ 6462 will complain about VLA uses that are not permitted by the draft 6463 standard, such as forming a pointer to VLA type or applying sizeof 6464 to a VLA variable. Note that it now appears that VLAs will not be 6465 part of C++14, but will be part of a separate document and then 6466 perhaps C++17. 6467 6468 void f(int n) { 6469 int a[n] = { 1, 2, 3 }; // throws std::bad_array_length if n < 3 6470 [&a]{ for (int i : a) { cout << i << endl; } }(); 6471 &a; // error, taking address of VLA 6472 } 6473 6474 * G++ supports the [12]C++1y [[deprecated]] attribute modulo bugs in 6475 the underlying [[gnu::deprecated]] attribute. Classes and functions 6476 can be marked deprecated and a diagnostic message added: 6477 6478 class A; 6479 int bar(int n); 6480 #if __cplusplus > 201103 6481 class [[deprecated("A is deprecated in C++14; Use B instead")]] A; 6482 [[deprecated("bar is unsafe; use foo() instead")]] 6483 int bar(int n); 6484 6485 int foo(int n); 6486 class B; 6487 #endif 6488 A aa; // warning: 'A' is deprecated : A is deprecated in C++14; Use B instead 6489 int j = bar(2); // warning: 'int bar(int)' is deprecated : bar is unsafe; use fo 6490 o() instead 6491 6492 * G++ supports [13]C++1y digit separators. Long numeric literals can 6493 be subdivided with a single quote ' to enhance readability: 6494 6495 int i = 1048576; 6496 int j = 1'048'576; 6497 int k = 0x10'0000; 6498 int m = 0'004'000'000; 6499 int n = 0b0001'0000'0000'0000'0000'0000; 6500 6501 double x = 1.602'176'565e-19; 6502 double y = 1.602'176'565e-1'9; 6503 6504 * G++ supports [14]C++1y generic (polymorphic) lambdas. 6505 6506 // a functional object that will increment any type 6507 auto incr = [](auto x) { return x++; }; 6508 6509 * As a GNU extension, G++ supports explicit template parameter syntax 6510 for generic lambdas. This can be combined in the expected way with 6511 the standard auto syntax. 6512 6513 // a functional object that will add two like-type objects 6514 auto add = [] <typename T> (T a, T b) { return a + b; }; 6515 6516 * G++ supports unconstrained generic functions as specified by 4.1.2 6517 and 5.1.1 of [15]N3889: Concepts Lite Specification. Briefly, auto 6518 may be used as a type-specifier in a parameter declaration of any 6519 function declarator in order to introduce an implicit function 6520 template parameter, akin to generic lambdas. 6521 6522 // the following two function declarations are equivalent 6523 auto incr(auto x) { return x++; } 6524 template <typename T> 6525 auto incr(T x) { return x++; } 6526 6527 Runtime Library (libstdc++) 6528 6529 * [16]Improved support for C++11, including: 6530 + support for <regex>; 6531 + The associative containers in <map> and <set> and the 6532 unordered associative containers in <unordered_map> and 6533 <unordered_set> meet the allocator-aware container 6534 requirements; 6535 * [17]Improved experimental support for the upcoming ISO C++ 6536 standard, C++14, including: 6537 + fixing constexpr member functions without const; 6538 + implementation of the std::exchange() utility function; 6539 + addressing tuples by type; 6540 + implemention of std::make_unique; 6541 + implemention of std::shared_lock; 6542 + making std::result_of SFINAE-friendly; 6543 + adding operator() to std::integral_constant; 6544 + adding user-defined literals for standard library types 6545 std::basic_string, std::chrono::duration, and std::complex; 6546 + adding two range overloads to non-modifying sequence oprations 6547 std::equal and std::mismatch; 6548 + adding IO manipulators for quoted strings; 6549 + adding constexpr members to <utility>, <complex>, <chrono>, 6550 and some containers; 6551 + adding compile-time std::integer_sequence; 6552 + adding cleaner transformation traits; 6553 + making <functional>s operator functors easier to use and more 6554 generic; 6555 * An implementation of std::experimental::optional. 6556 * An implementation of std::experimental::string_view. 6557 * The non-standard function std::copy_exception has been deprecated 6558 and will be removed in a future version. std::make_exception_ptr 6559 should be used instead. 6560 6561 Fortran 6562 6563 * Compatibility notice: 6564 + Module files: The version of the module files (.mod) has been 6565 incremented; additionally, module files are now compressed. 6566 Fortran MODULEs compiled by earlier GCC versions have to be 6567 recompiled, when they are USEd by files compiled with GCC 4.9. 6568 GCC 4.9 is not able to read .mod files of earlier GCC 6569 versions; attempting to do so gives an error message. Note: 6570 The ABI of the produced assembler data itself has not changed: 6571 object files and libraries are fully compatible with older 6572 versions (except as stated below). 6573 + ABI changes: 6574 o The [18]argument passing ABI has changed for scalar dummy 6575 arguments of type INTEGER, REAL, COMPLEX and LOGICAL, 6576 which have both the VALUE and the OPTIONAL attributes. 6577 o To support finalization the virtual table associated with 6578 polymorphic variables has changed. Code containing CLASS 6579 should be recompiled, including all files which define 6580 derived types involved in the type definition used by 6581 polymorphic variables. (Note: Due to the incremented 6582 module version, trying to mix old code with new code will 6583 usually give an error message.) 6584 + GNU Fortran no longer deallocates allocatable variables or 6585 allocatable components of variables declared in the main 6586 program. Since Fortran 2008, the standard explicitly states 6587 that variables declared in the Fortran main program 6588 automatically have the SAVE attribute. 6589 + When opening files, the close-on-exec flag is set if the 6590 system supports such a feature. This is generally considered 6591 good practice these days, but if there is a need to pass file 6592 descriptors to child processes the parent process must now 6593 remember to clear the close-on-exec flag by calling fcntl(), 6594 e.g. via ISO_C_BINDING, before executing the child process. 6595 * The deprecated command-line option -fno-whole-file has been 6596 removed. (-fwhole-file is the default since GCC 4.6.) 6597 -fwhole-file/-fno-whole-file continue to be accepted but do not 6598 influence the code generation. 6599 * The compiler no longer unconditionally warns about DO loops with 6600 zero iterations. This warning is now controlled by the -Wzerotrip 6601 option, which is implied by -Wall. 6602 * The new NO_ARG_CHECK attribute of the [19]!GCC$ directive can be 6603 used to disable the type-kind-rank (TKR) argument check for a dummy 6604 argument. The feature is similar to ISO/IEC TS 29133:2012's 6605 TYPE(*), except that it additionally also disables the rank check. 6606 Variables with NO_ARG_CHECK have to be dummy arguments and may only 6607 be used as argument to ISO_C_BINDING's C_LOC and as actual argument 6608 to another NO_ARG_CHECK dummy argument; also the other constraints 6609 of TYPE(*) apply. The dummy arguments should be declared as scalar 6610 or assumed-size variable of type type(*) (recommended) - or of type 6611 integer, real, complex or logical. With NO_ARG_CHECK, a pointer to 6612 the data without further type or shape information is passed, 6613 similar to C's void*. Note that also TS 29113's 6614 type(*),dimension(..) accepts arguments of any type and rank; 6615 contrary to NO_ARG_CHECK assumed-rank arguments pass an array 6616 descriptor which contains the array shape and stride of the 6617 argument. 6618 * [20]Fortran 2003: 6619 + Finalization is now supported. It is currently only done for a 6620 subset of those situations in which it should occur. 6621 + Experimental support for scalar character components with 6622 deferred length (i.e. allocatable string length) in derived 6623 types has been added. (Deferred-length character variables are 6624 supported since GCC 4.6.) 6625 * [21]Fortran 2008: 6626 + When STOP or ERROR STOP are used to terminate the execution 6627 and any exception (but inexact) is signaling, a warning is 6628 printed to ERROR_UNIT, indicating which exceptions are 6629 signaling. The [22]-ffpe-summary= command-line option can be 6630 used to fine-tune for which exceptions the warning should be 6631 shown. 6632 + Rounding on input (READ) is now handled on systems where 6633 strtod honours the rounding mode. (For output, rounding is 6634 supported since GCC 4.5.) Note that for input, the compatible 6635 rounding mode is handled as nearest (i.e., rounding to an even 6636 least significant [cf. IEC 60559:1989] for a tie, while 6637 compatible rounds away from zero in that case). 6638 6639 Go 6640 6641 * GCC 4.9 provides a complete implementation of the Go 1.2.1 release. 6642 6643 New Targets and Target Specific Improvements 6644 6645 AArch64 6646 6647 * The ARMv8-A crypto and CRC instructions are now supported through 6648 intrinsics. These are enabled when the architecture supports these 6649 and are available through the -march=armv8-a+crc and 6650 -march=armv8-a+crypto options. 6651 * Initial support for ILP32 has now been added to the compiler. This 6652 is now available through the command-line option -mabi=ilp32. 6653 Support for ILP32 is considered experimental as the ABI 6654 specification is still beta. 6655 * Coverage of more of the ISA including the SIMD extensions has been 6656 added. The Advanced SIMD intrinsics have also been improved. 6657 * The new local register allocator (LRA) is now on by default for the 6658 AArch64 backend. 6659 * The REE (Redundant extension elimination) pass has now been enabled 6660 by default for the AArch64 backend. 6661 * Tuning for the Cortex-A53 and Cortex-A57 has been improved. 6662 * Initial big.LITTLE tuning support for the combination of Cortex-A57 6663 and Cortex-A53 was added through the -mcpu=cortex-a57.cortex-a53 6664 option. 6665 * A number of structural changes have been made to both the ARM and 6666 AArch64 backends to facilitate improved code-generation. 6667 * As of GCC 4.9.2 a workaround for the ARM Cortex-A53 erratum 835769 6668 has been added and can be enabled by giving the 6669 -mfix-cortex-a53-835769 option. Alternatively it can be enabled by 6670 default by configuring GCC with the --enable-fix-cortex-a53-835769 6671 option. 6672 6673 ARC 6674 6675 * A port for Synopsys Designware ARC has been contributed by Embecosm 6676 and Synopsys Inc. 6677 6678 ARM 6679 6680 * Use of Advanced SIMD (Neon) for 64-bit scalar computations has been 6681 disabled by default. This was found to generate better code in only 6682 a small number of cases. It can be turned back on with the 6683 -mneon-for-64bits option. 6684 * Further support for the ARMv8-A architecture, notably implementing 6685 the restriction around IT blocks in the Thumb32 instruction set has 6686 been added. The -mrestrict-it option can be used with 6687 -march=armv7-a or the -march=armv7ve options to make code 6688 generation fully compatible with the deprecated instructions in 6689 ARMv8-A. 6690 * Support has now been added for the ARMv7ve variant of the 6691 architecture. This can be used by the -march=armv7ve option. 6692 * The ARMv8-A crypto and CRC instructions are now supported through 6693 intrinsics and are available through the -march=armv8-a+crc and 6694 mfpu=crypto-neon-fp-armv8 options. 6695 * LRA is now on by default for the ARM target. This can be turned off 6696 using the -mno-lra option. This option is a purely transitionary 6697 command-line option and will be removed in a future release. We are 6698 interested in any bug reports regarding functional and performance 6699 regressions with LRA. 6700 * A new option -mslow-flash-data to improve performance of programs 6701 fetching data on slow flash memory has now been introduced for the 6702 ARMv7-M profile cores. 6703 * A new option -mpic-data-is-text-relative for targets that allows 6704 data segments to be relative to text segments has been added. This 6705 is on by default for all targets except VxWorks RTP. 6706 * A number of infrastructural changes have been made to both the ARM 6707 and AArch64 backends to facilitate improved code-generation. 6708 * GCC now supports Cortex-A12 and the Cortex-R7 through the 6709 -mcpu=cortex-a12 and -mcpu=cortex-r7 options. 6710 * GCC now has tuning for the Cortex-A57 and Cortex-A53 through the 6711 -mcpu=cortex-a57 and -mcpu=cortex-a53 options. 6712 * Initial big.LITTLE tuning support for the combination of Cortex-A57 6713 and Cortex-A53 was added through the -mcpu=cortex-a57.cortex-a53 6714 option. Similar support was added for the combination of Cortex-A15 6715 and Cortex-A7 through the -mcpu=cortex-a15.cortex-a7 option. 6716 * Further performance optimizations for the Cortex-A15 and the 6717 Cortex-M4 have been added. 6718 * A number of code generation improvements for Thumb2 to reduce code 6719 size when compiling for the M-profile processors. 6720 6721 AVR 6722 6723 * A new command-line option -mfract-convert-truncate has been added. 6724 It allows compiler to use truncation instead of rounding towards 6725 zero for fractional fixed-point types. 6726 6727 IA-32/x86-64 6728 6729 * -mfpmath=sse is now implied by -ffast-math on all targets where 6730 SSE2 is supported. 6731 * Intel AVX-512 support was added to GCC. That includes inline 6732 assembly support, new registers and extending existing ones, new 6733 intrinsics (covered by corresponding testsuite), and basic 6734 autovectorization. AVX-512 instructions are available via the 6735 following GCC switches: AVX-512 foundation instructions: -mavx512f, 6736 AVX-512 prefetch instructions: -mavx512pf, AVX-512 exponential and 6737 reciprocal instructions: -mavx512er, AVX-512 conflict detection 6738 instructions: -mavx512cd. 6739 * It is now possible to call x86 intrinsics from select functions in 6740 a file that are tagged with the corresponding target attribute 6741 without having to compile the entire file with the -mxxx option. 6742 This improves the usability of x86 intrinsics and is particularly 6743 useful when doing [23]Function Multiversioning. 6744 * GCC now supports the new Intel microarchitecture named Silvermont 6745 through -march=silvermont. 6746 * GCC now supports the new Intel microarchitecture named Broadwell 6747 through -march=broadwell. 6748 * Optimizing for other Intel microarchitectures have been renamed to 6749 -march=nehalem, westmere, sandybridge, ivybridge, haswell, bonnell. 6750 * -march=generic has been retuned for better support of Intel core 6751 and AMD Bulldozer architectures. Performance of AMD K7, K8, Intel 6752 Pentium-M, and Pentium4 based CPUs is no longer considered 6753 important for generic. 6754 * -mtune=intel can now be used to generate code running well on the 6755 most current Intel processors, which are Haswell and Silvermont for 6756 GCC 4.9. 6757 * Support to encode 32-bit assembly instructions in 16-bit format is 6758 now available through the -m16 command-line option. 6759 * Better inlining of memcpy and memset that is aware of value ranges 6760 and produces shorter alignment prologues. 6761 * -mno-accumulate-outgoing-args is now honored when unwind 6762 information is output. Argument accumulation is also now turned off 6763 for portions of programs optimized for size. 6764 * Support for new AMD family 15h processors (Excavator core) is now 6765 available through the -march=bdver4 and -mtune=bdver4 options. 6766 6767 MSP430 6768 6769 * A new command-line option -mcpu= has been added to the MSP430 6770 backend. This option is used to specify the ISA to be used. 6771 Accepted values are msp430 (the default), msp430x and msp430xv2. 6772 The ISA is no longer deduced from the -mmcu= option as there are 6773 far too many different MCU names. The -mmcu= option is still 6774 supported, and this is still used to select linker scripts and 6775 generate a C preprocessor symbol that will be recognised by the 6776 msp430.h header file. 6777 6778 NDS32 6779 6780 * A new nds32 port supports the 32-bit architecture from Andes 6781 Technology Corporation. 6782 * The port provides initial support for the V2, V3, V3m instruction 6783 set architectures. 6784 6785 Nios II 6786 6787 * A port for the Altera Nios II has been contributed by Mentor 6788 Graphics. 6789 6790 PowerPC / PowerPC64 / RS6000 6791 6792 * GCC now supports Power ISA 2.07, which includes support for 6793 Hardware Transactional Memory (HTM), Quadword atomics and several 6794 VMX and VSX additions, including Crypto, 64-bit integer, 128-bit 6795 integer and decimal integer operations. 6796 * Support for the POWER8 processor is now available through the 6797 -mcpu=power8 and -mtune=power8 options. 6798 * The libitm library has been modified to add a HTM fastpath that 6799 automatically uses POWER's HTM hardware instructions when it is 6800 executing on a HTM enabled processor. 6801 * Support for the new powerpc64le-linux platform has been added. It 6802 defaults to generating code that conforms to the ELFV2 ABI. 6803 6804 S/390, System z 6805 6806 * Support for the Transactional Execution Facility included with the 6807 IBM zEnterprise zEC12 processor has been added. A set of GCC style 6808 builtins as well as XLC style builtins are provided. The builtins 6809 are enabled by default when using the -march=zEC12 option but can 6810 explicitly be disabled with -mno-htm. Using the GCC builtins also 6811 libitm supports hardware transactions on S/390. 6812 * The hotpatch features allows to prepare functions for hotpatching. 6813 A certain amount of bytes is reserved before the function entry 6814 label plus a NOP is inserted at its very beginning to implement a 6815 backward jump when applying a patch. The feature can either be 6816 enabled per compilation unit via the command-line option -mhotpatch 6817 or per function using the hotpatch attribute. 6818 * The shrink wrap optimization is now supported on S/390 and enabled 6819 by default. 6820 * A major rework of the routines to determine which registers need to 6821 be saved and restored in function prologue/epilogue now allow to 6822 use floating point registers as save slots. This will happen for 6823 certain leaf function with -march=z10 or higher. 6824 * The LRA rtl pass replaces reload by default on S/390. 6825 6826 RX 6827 6828 * The port now allows to specify the RX100, RX200, and RX600 6829 processors with the command-line options -mcpu=rx100, -mcpu=rx200 6830 and -mcpu=rx600. 6831 6832 SH 6833 6834 * Minor improvements to code generated for integer arithmetic and 6835 code that involves the T bit. 6836 * Added support for the SH2A clips and clipu instructions. The 6837 compiler will now try to utilize them for min/max expressions such 6838 as max (-128, min (127, x)). 6839 * Added support for the cmp/str instruction through built-in 6840 functions such as __builtin_strlen. When not optimizing for size, 6841 the compiler will now expand calls to e.g. strlen as an inlined 6842 sequences which utilize the cmp/str instruction. 6843 * Improved code generated around volatile memory loads and stores. 6844 * The option -mcbranchdi has been deprecated. Specifying it will 6845 result in a warning and will not influence code generation. 6846 * The option -mcmpeqdi has been deprecated. Specifying it will result 6847 in a warning and will not influence code generation. 6848 6849 GCC 4.9.1 6850 6851 This is the [24]list of problem reports (PRs) from GCC's bug tracking 6852 system that are known to be fixed in the 4.9.1 release. This list might 6853 not be complete (that is, it is possible that some PRs that have been 6854 fixed are not listed here). 6855 6856 Version 4.0 of the OpenMP specification is supported even in Fortran, 6857 not just C and C++. 6858 6859 GCC 4.9.2 6860 6861 This is the [25]list of problem reports (PRs) from GCC's bug tracking 6862 system that are known to be fixed in the 4.9.2 release. This list might 6863 not be complete (that is, it is possible that some PRs that have been 6864 fixed are not listed here). 6865 6866 GCC 4.9.3 6867 6868 This is the [26]list of problem reports (PRs) from GCC's bug tracking 6869 system that are known to be fixed in the 4.9.3 release. This list might 6870 not be complete (that is, it is possible that some PRs that have been 6871 fixed are not listed here). 6872 6873 GCC 4.9.4 6874 6875 This is the [27]list of problem reports (PRs) from GCC's bug tracking 6876 system that are known to be fixed in the 4.9.4 release. This list might 6877 not be complete (that is, it is possible that some PRs that have been 6878 fixed are not listed here). 6879 6880 6881 For questions related to the use of GCC, please consult these web 6882 pages and the [28]GCC manuals. If that fails, the 6883 [29]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 6884 web pages and the development of GCC are welcome on our developer 6885 list at [30]gcc (a] gcc.gnu.org. All of [31]our lists have public 6886 archives. 6887 6888 Copyright (C) [32]Free Software Foundation, Inc. Verbatim copying and 6889 distribution of this entire article is permitted in any medium, 6890 provided this notice is preserved. 6891 6892 These pages are [33]maintained by the GCC team. Last modified 6893 2023-01-19. 6894 6895 References 6896 6897 1. https://gcc.gnu.org/ml/gcc-patches/2013-05/msg00728.html 6898 2. https://gcc.gnu.org/PR60825 6899 3. https://gcc.gnu.org/gcc-4.9/porting_to.html 6900 4. https://www.openmp.org/specifications/ 6901 5. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Optimize-Options.html#index-fsimd-cost-model-908 6902 6. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Language-Independent-Options.html#index-fdiagnostics-color-252 6903 7. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Loop-Specific-Pragmas.html 6904 8. http://gcc.gnu.org/projects/cxx1y.html 6905 9. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3638.html 6906 10. http://gcc.gnu.org/projects/cxx1y.html 6907 11. http://gcc.gnu.org/projects/cxx1y.html 6908 12. http://gcc.gnu.org/projects/cxx1y.html 6909 13. http://gcc.gnu.org/projects/cxx1y.html 6910 14. http://gcc.gnu.org/projects/cxx1y.html 6911 15. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3889.pdf 6912 16. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/libstdc++/manual/manual/status.html#status.iso.2011 6913 17. https://gcc.gnu.org/onlinedocs/libstdc++/manual/status.html#status.iso.2014 6914 18. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gfortran/Argument-passing-conventions.html 6915 19. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gfortran/GNU-Fortran-Compiler-Directives.html 6916 20. https://gcc.gnu.org/wiki/Fortran2003Status 6917 21. https://gcc.gnu.org/wiki/Fortran2008Status 6918 22. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gfortran/Debugging-Options.html 6919 23. https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Function-Multiversioning.html 6920 24. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.9.1 6921 25. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.9.2 6922 26. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.9.3 6923 27. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.9.4 6924 28. https://gcc.gnu.org/onlinedocs/ 6925 29. mailto:gcc-help (a] gcc.gnu.org 6926 30. mailto:gcc (a] gcc.gnu.org 6927 31. https://gcc.gnu.org/lists.html 6928 32. https://www.fsf.org/ 6929 33. https://gcc.gnu.org/about.html 6930 ====================================================================== 6931 http://gcc.gnu.org/gcc-4.8/index.html 6932 6933 GCC 4.8 Release Series 6934 6935 (This release series is no longer supported.) 6936 6937 June 23, 2015 6938 6939 The [1]GNU project and the GCC developers are pleased to announce the 6940 release of GCC 4.8.5. 6941 6942 This release is a bug-fix release, containing fixes for regressions in 6943 GCC 4.8.4 relative to previous releases of GCC. 6944 6945 Release History 6946 6947 GCC 4.8.5 6948 June 23, 2015 ([2]changes, [3]documentation) 6949 6950 GCC 4.8.4 6951 December 19, 2014 ([4]changes, [5]documentation) 6952 6953 GCC 4.8.3 6954 May 22, 2014 ([6]changes, [7]documentation) 6955 6956 GCC 4.8.2 6957 October 16, 2013 ([8]changes, [9]documentation) 6958 6959 GCC 4.8.1 6960 May 31, 2013 ([10]changes, [11]documentation) 6961 6962 GCC 4.8.0 6963 March 22, 2013 ([12]changes, [13]documentation) 6964 6965 References and Acknowledgements 6966 6967 GCC used to stand for the GNU C Compiler, but since the compiler 6968 supports several other languages aside from C, it now stands for the 6969 GNU Compiler Collection. 6970 6971 A list of [14]successful builds is updated as new information becomes 6972 available. 6973 6974 The GCC developers would like to thank the numerous people that have 6975 contributed new features, improvements, bug fixes, and other changes as 6976 well as test results to GCC. This [15]amazing group of volunteers is 6977 what makes GCC successful. 6978 6979 For additional information about GCC please refer to the [16]GCC 6980 project web site or contact the [17]GCC development mailing list. 6981 6982 To obtain GCC please use [18]our mirror sites or [19]our version 6983 control system. 6984 6985 6986 For questions related to the use of GCC, please consult these web 6987 pages and the [20]GCC manuals. If that fails, the 6988 [21]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 6989 web pages and the development of GCC are welcome on our developer 6990 list at [22]gcc (a] gcc.gnu.org. All of [23]our lists have public 6991 archives. 6992 6993 Copyright (C) [24]Free Software Foundation, Inc. Verbatim copying and 6994 distribution of this entire article is permitted in any medium, 6995 provided this notice is preserved. 6996 6997 These pages are [25]maintained by the GCC team. Last modified 6998 2022-10-26. 6999 7000 References 7001 7002 1. http://www.gnu.org/ 7003 2. http://gcc.gnu.org/gcc-4.8/changes.html 7004 3. https://gcc.gnu.org/onlinedocs/4.8.5/ 7005 4. http://gcc.gnu.org/gcc-4.8/changes.html 7006 5. https://gcc.gnu.org/onlinedocs/4.8.4/ 7007 6. http://gcc.gnu.org/gcc-4.8/changes.html 7008 7. https://gcc.gnu.org/onlinedocs/4.8.3/ 7009 8. http://gcc.gnu.org/gcc-4.8/changes.html 7010 9. https://gcc.gnu.org/onlinedocs/4.8.2/ 7011 10. http://gcc.gnu.org/gcc-4.8/changes.html 7012 11. https://gcc.gnu.org/onlinedocs/4.8.1/ 7013 12. http://gcc.gnu.org/gcc-4.8/changes.html 7014 13. https://gcc.gnu.org/onlinedocs/4.8.0/ 7015 14. http://gcc.gnu.org/gcc-4.8/buildstat.html 7016 15. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 7017 16. http://gcc.gnu.org/index.html 7018 17. mailto:gcc (a] gcc.gnu.org 7019 18. http://gcc.gnu.org/mirrors.html 7020 19. http://gcc.gnu.org/git.html 7021 20. https://gcc.gnu.org/onlinedocs/ 7022 21. mailto:gcc-help (a] gcc.gnu.org 7023 22. mailto:gcc (a] gcc.gnu.org 7024 23. https://gcc.gnu.org/lists.html 7025 24. https://www.fsf.org/ 7026 25. https://gcc.gnu.org/about.html 7027 ====================================================================== 7028 http://gcc.gnu.org/gcc-4.8/changes.html 7029 7030 GCC 4.8 Release Series 7031 Changes, New Features, and Fixes 7032 7033 Caveats 7034 7035 GCC now uses C++ as its implementation language. This means that to 7036 build GCC from sources, you will need a C++ compiler that understands 7037 C++ 2003. For more details on the rationale and specific changes, 7038 please refer to the [1]C++ conversion page. 7039 7040 To enable the Graphite framework for loop optimizations you now need 7041 CLooG version 0.18.0 and ISL version 0.11.1. Both can be obtained from 7042 the [2]GCC infrastructure directory. The installation manual contains 7043 more information about requirements to build GCC. 7044 7045 GCC now uses a more aggressive analysis to derive an upper bound for 7046 the number of iterations of loops using constraints imposed by language 7047 standards. This may cause non-conforming programs to no longer work as 7048 expected, such as SPEC CPU 2006 464.h264ref and 416.gamess. A new 7049 option, -fno-aggressive-loop-optimizations, was added to disable this 7050 aggressive analysis. In some loops that have known constant number of 7051 iterations, but undefined behavior is known to occur in the loop before 7052 reaching or during the last iteration, GCC will warn about the 7053 undefined behavior in the loop instead of deriving lower upper bound of 7054 the number of iterations for the loop. The warning can be disabled with 7055 -Wno-aggressive-loop-optimizations. 7056 7057 On ARM, a bug has been fixed in GCC's implementation of the AAPCS rules 7058 for the layout of vectors that could lead to wrong code being 7059 generated. Vectors larger than 8 bytes in size are now by default 7060 aligned to an 8-byte boundary. This is an ABI change: code that makes 7061 explicit use of vector types may be incompatible with binary objects 7062 built with older versions of GCC. Auto-vectorized code is not affected 7063 by this change. 7064 7065 On AVR, support has been removed for the command-line option 7066 -mshort-calls deprecated in GCC 4.7. 7067 7068 On AVR, the configure option --with-avrlibc supported since GCC 4.7.2 7069 is turned on per default for all non-RTEMS configurations. This option 7070 arranges for a better integration of [3]AVR Libc with avr-gcc. For 7071 technical details, see [4]PR54461. To turn off the option in non-RTEMS 7072 configurations, use --with-avrlibc=no. If the compiler is configured 7073 for RTEMS, the option is always turned off. 7074 7075 More information on porting to GCC 4.8 from previous versions of GCC 7076 can be found in the [5]porting guide for this release. 7077 7078 General Optimizer Improvements (and Changes) 7079 7080 * DWARF4 is now the default when generating DWARF debug information. 7081 When -g is used on a platform that uses DWARF debugging 7082 information, GCC will now default to -gdwarf-4 7083 -fno-debug-types-section. 7084 GDB 7.5, Valgrind 3.8.0 and elfutils 0.154 debug information 7085 consumers support DWARF4 by default. Before GCC 4.8 the default 7086 version used was DWARF2. To make GCC 4.8 generate an older DWARF 7087 version use -g together with -gdwarf-2 or -gdwarf-3. The default 7088 for Darwin and VxWorks is still -gdwarf-2 -gstrict-dwarf. 7089 * A new general optimization level, -Og, has been introduced. It 7090 addresses the need for fast compilation and a superior debugging 7091 experience while providing a reasonable level of run-time 7092 performance. Overall experience for development should be better 7093 than the default optimization level -O0. 7094 * A new option -ftree-partial-pre was added to control the partial 7095 redundancy elimination (PRE) optimization. This option is enabled 7096 by default at the -O3 optimization level, and it makes PRE more 7097 aggressive. 7098 * The option -fconserve-space has been removed; it was no longer 7099 useful on most targets since GCC supports putting variables into 7100 BSS without making them common. 7101 * The struct reorg and matrix reorg optimizations (command-line 7102 options -fipa-struct-reorg and -fipa-matrix-reorg) have been 7103 removed. They did not always work correctly, nor did they work with 7104 link-time optimization (LTO), hence were only applicable to 7105 programs consisting of a single translation unit. 7106 * Several scalability bottle-necks have been removed from GCC's 7107 optimization passes. Compilation of extremely large functions, e.g. 7108 due to the use of the flatten attribute in the "Eigen" C++ linear 7109 algebra templates library, is significantly faster than previous 7110 releases of GCC. 7111 * Link-time optimization (LTO) improvements: 7112 + LTO partitioning has been rewritten for better reliability and 7113 maintanibility. Several important bugs leading to link 7114 failures have been fixed. 7115 * Interprocedural optimization improvements: 7116 + A new symbol table has been implemented. It builds on existing 7117 callgraph and varpool modules and provide a new API. Unusual 7118 symbol visibilities and aliases are handled more consistently 7119 leading to, for example, more aggressive unreachable code 7120 removal with LTO. 7121 + The inline heuristic can now bypass limits on the size of of 7122 inlined functions when the inlining is particularly 7123 profitable. This happens, for example, when loop bounds or 7124 array strides get propagated. 7125 + Values passed through aggregates (either by value or 7126 reference) are now propagated at the inter-procedural level 7127 leading to better inlining decisions (for example in the case 7128 of Fortran array descriptors) and devirtualization. 7129 * [6]AddressSanitizer , a fast memory error detector, has been added 7130 and can be enabled via -fsanitize=address. Memory access 7131 instructions will be instrumented to detect heap-, stack-, and 7132 global-buffer overflow as well as use-after-free bugs. To get nicer 7133 stacktraces, use -fno-omit-frame-pointer. The AddressSanitizer is 7134 available on IA-32/x86-64/x32/PowerPC/PowerPC64 GNU/Linux and on 7135 x86-64 Darwin. 7136 * [7]ThreadSanitizer has been added and can be enabled via 7137 -fsanitize=thread. Instructions will be instrumented to detect data 7138 races. The ThreadSanitizer is available on x86-64 GNU/Linux. 7139 * A new local register allocator (LRA) has been implemented, which 7140 replaces the 26 year old reload pass and improves generated code 7141 quality. For now it is active on the IA-32 and x86-64 targets. 7142 * Support for transactional memory has been implemented on the 7143 following architectures: IA-32/x86-64, ARM, PowerPC, SH, SPARC, and 7144 Alpha. 7145 7146 New Languages and Language specific improvements 7147 7148 C family 7149 7150 * Each diagnostic emitted now includes the original source line and a 7151 caret '^' indicating the column. The option 7152 -fno-diagnostics-show-caret suppresses this information. 7153 * The option -ftrack-macro-expansion=2 is now enabled by default. 7154 This allows the compiler to display the macro expansion stack in 7155 diagnostics. Combined with the caret information, an example 7156 diagnostic showing these two features is: 7157 7158 t.c:1:94: error: invalid operands to binary < (have `struct mystruct' and `float 7159 ') 7160 #define MYMAX(A,B) __extension__ ({ __typeof__(A) __a = (A); __typeof__(B) _ 7161 _b = (B); __a < __b ? __b : __a; }) 7162 7163 ^ 7164 t.c:7:7: note: in expansion of macro 'MYMAX' 7165 X = MYMAX(P, F); 7166 ^ 7167 7168 * A new -Wsizeof-pointer-memaccess warning has been added (also 7169 enabled by -Wall) to warn about suspicious length parameters to 7170 certain string and memory built-in functions if the argument uses 7171 sizeof. This warning warns e.g. about memset (ptr, 0, sizeof 7172 (ptr)); if ptr is not an array, but a pointer, and suggests a 7173 possible fix, or about memcpy (&foo, ptr, sizeof (&foo));. 7174 * The new option -Wpedantic is an alias for -pedantic, which is now 7175 deprecated. The forms -Wno-pedantic, -Werror=pedantic, and 7176 -Wno-error=pedantic work in the same way as for any other -W 7177 option. One caveat is that -Werror=pedantic is not equivalent to 7178 -pedantic-errors, since the latter makes into errors some warnings 7179 that are not controlled by -Wpedantic, and the former only affects 7180 diagnostics that are disabled when using -Wno-pedantic. 7181 * The option -Wshadow no longer warns if a declaration shadows a 7182 function declaration, unless the former declares a function or 7183 pointer to function, because this is [8]a common and valid case in 7184 real-world code. 7185 7186 C++ 7187 7188 * G++ now implements the [9]C++11 thread_local keyword; this differs 7189 from the GNU __thread keyword primarily in that it allows dynamic 7190 initialization and destruction semantics. Unfortunately, this 7191 support requires a run-time penalty for references to 7192 non-function-local thread_local variables defined in a different 7193 translation unit even if they don't need dynamic initialization, so 7194 users may want to continue to use __thread for TLS variables with 7195 static initialization semantics. 7196 If the programmer can be sure that no use of the variable in a 7197 non-defining TU needs to trigger dynamic initialization (either 7198 because the variable is statically initialized, or a use of the 7199 variable in the defining TU will be executed before any uses in 7200 another TU), they can avoid this overhead with the 7201 -fno-extern-tls-init option. 7202 OpenMP threadprivate variables now also support dynamic 7203 initialization and destruction by the same mechanism. 7204 * G++ now implements the [10]C++11 attribute syntax, e.g. 7205 7206 [[noreturn]] void f(); 7207 7208 and also the alignment specifier, e.g. 7209 7210 alignas(double) int i; 7211 7212 * G++ now implements [11]C++11 inheriting constructors, e.g. 7213 7214 struct A { A(int); }; 7215 struct B: A { using A::A; }; // defines B::B(int) 7216 B b(42); // OK 7217 7218 * As of GCC 4.8.1, G++ implements the change to decltype semantics 7219 from [12]N3276. 7220 7221 struct A f(); 7222 decltype(f()) g(); // OK, return type of f() is not required to be complete. 7223 7224 * As of GCC 4.8.1, G++ implements [13]C++11 ref-qualifiers, e.g. 7225 7226 struct A { int f() &; }; 7227 int i = A().f(); // error, f() requires an lvalue object 7228 7229 * G++ now supports a -std=c++1y option for experimentation with 7230 features proposed for the next revision of the standard, expected 7231 around 2014. Currently the only difference from -std=c++11 is 7232 support for return type deduction in normal functions, as proposed 7233 in [14]N3386. Status of C++1y features in GCC 4.8 can be found 7234 [15]here. 7235 * The G++ namespace association extension, __attribute ((strong)), 7236 has been deprecated. Inline namespaces should be used instead. 7237 * G++ now supports a -fext-numeric-literal option to control whether 7238 GNU numeric literal suffixes are accepted as extensions or 7239 processed as C++11 user-defined numeric literal suffixes. The flag 7240 is on (use suffixes for GNU literals) by default for -std=gnu++*, 7241 and -std=c++98. The flag is off (use suffixes for user-defined 7242 literals) by default for -std=c++11 and later. 7243 7244 Runtime Library (libstdc++) 7245 7246 * [16]Improved experimental support for the new ISO C++ standard, 7247 C++11, including: 7248 + forward_list meets the allocator-aware container requirements; 7249 + this_thread::sleep_for(), this_thread::sleep_until() and 7250 this_thread::yield() are defined without requiring the 7251 configure option --enable-libstdcxx-time; 7252 * Improvements to <random>: 7253 + SSE optimized normal_distribution. 7254 + Use of hardware RNG instruction for random_device on new x86 7255 processors (requires the assembler to support the 7256 instruction.) 7257 and <ext/random>: 7258 + New random number engine simd_fast_mersenne_twister_engine 7259 with an optimized SSE implementation. 7260 + New random number distributions beta_distribution, 7261 normal_mv_distribution, rice_distribution, 7262 nakagami_distribution, pareto_distribution, k_distribution, 7263 arcsine_distribution, hoyt_distribution. 7264 * Added --disable-libstdcxx-verbose configure option to disable 7265 diagnostic messages issued when a process terminates abnormally. 7266 This may be useful for embedded systems to reduce the size of 7267 executables that link statically to the library. 7268 7269 Fortran 7270 7271 * Compatibility notice: 7272 + Module files: The version of module files (.mod) has been 7273 incremented. Fortran MODULEs compiled by earlier GCC versions 7274 have to be recompiled, when they are USEd by files compiled 7275 with GCC 4.8. GCC 4.8 is not able to read .mod files created 7276 by earlier versions; attempting to do so gives an error 7277 message. 7278 Note: The ABI of the produced assembler data itself has not 7279 changed; object files and libraries are fully compatible with 7280 older versions except as noted below. 7281 + ABI: Some internal names (used in the assembler/object file) 7282 have changed for symbols declared in the specification part of 7283 a module. If an affected module - or a file using it via use 7284 association - is recompiled, the module and all files which 7285 directly use such symbols have to be recompiled as well. This 7286 change only affects the following kind of module symbols: 7287 o Procedure pointers. Note: C-interoperable function 7288 pointers (type(c_funptr)) are not affected nor are 7289 procedure-pointer components. 7290 o Deferred-length character strings. 7291 * The [17]BACKTRACE intrinsic subroutine has been added. It shows a 7292 backtrace at an arbitrary place in user code; program execution 7293 continues normally afterwards. 7294 * The [18]-Wc-binding-type warning option has been added (disabled by 7295 default). It warns if the a variable might not be C interoperable; 7296 in particular, if the variable has been declared using an intrinsic 7297 type with default kind instead of using a kind parameter defined 7298 for C interoperability in the intrinsic ISO_C_Binding module. 7299 Before, this warning was always printed. The -Wc-binding-type 7300 option is enabled by -Wall. 7301 * The [19]-Wrealloc-lhs and -Wrealloc-lhs-all warning command-line 7302 options have been added, which diagnose when code is inserted for 7303 automatic (re)allocation of a variable during assignment. This 7304 option can be used to decide whether it is safe to use 7305 [20]-fno-realloc-lhs. Additionally, it can be used to find 7306 automatic (re)allocation in hot loops. (For arrays, replacing 7307 "var=" by "var(:)=" disables the automatic reallocation.) 7308 * The [21]-Wcompare-reals command-line option has been added. When 7309 this is set, warnings are issued when comparing REAL or COMPLEX 7310 types for equality and inequality; consider replacing a == b by 7311 abs(a-b) < eps with a suitable eps. -Wcompare-reals is enabled by 7312 -Wextra. 7313 * The [22]-Wtarget-lifetime command-line option has been added 7314 (enabled with -Wall), which warns if the pointer in a pointer 7315 assignment might outlive its target. 7316 * Reading floating point numbers which use "q" for the exponential 7317 (such as 4.0q0) is now supported as vendor extension for better 7318 compatibility with old data files. It is strongly recommended to 7319 use for I/O the equivalent but standard conforming "e" (such as 7320 4.0e0). 7321 (For Fortran source code, consider replacing the "q" in 7322 floating-point literals by a kind parameter (e.g. 4.0e0_qp with a 7323 suitable qp). Note that - in Fortran source code - replacing "q" by 7324 a simple "e" is not equivalent.) 7325 * The GFORTRAN_TMPDIR environment variable for specifying a 7326 non-default directory for files opened with STATUS="SCRATCH", is 7327 not used anymore. Instead gfortran checks the POSIX/GNU standard 7328 TMPDIR environment variable. If TMPDIR is not defined, gfortran 7329 falls back to other methods to determine the directory for 7330 temporary files as documented in the [23]user manual. 7331 * [24]Fortran 2003: 7332 + Support for unlimited polymorphic variables (CLASS(*)) has 7333 been added. Nonconstant character lengths are not yet 7334 supported. 7335 * [25]TS 29113: 7336 + Assumed types (TYPE(*)) are now supported. 7337 + Experimental support for assumed-rank arrays (dimension(..)) 7338 has been added. Note that currently gfortran's own array 7339 descriptor is used, which is different from the one defined in 7340 TS29113, see [26]gfortran's header file or use the [27]Chasm 7341 Language Interoperability Tools. 7342 7343 Go 7344 7345 * GCC 4.8.2 provides a complete implementation of the Go 1.1.2 7346 release. 7347 * GCC 4.8.0 and 4.8.1 implement a preliminary version of the Go 1.1 7348 release. The library support is not quite complete. 7349 * Go has been tested on GNU/Linux and Solaris platforms for various 7350 processors including x86, x86_64, PowerPC, SPARC, and Alpha. It may 7351 work on other platforms as well. 7352 7353 New Targets and Target Specific Improvements 7354 7355 AArch64 7356 7357 * A new port has been added to support AArch64, the new 64-bit 7358 architecture from ARM. Note that this is a separate port from the 7359 existing 32-bit ARM port. 7360 * The port provides initial support for the Cortex-A53 and the 7361 Cortex-A57 processors with the command line options 7362 -mcpu=cortex-a53 and -mcpu=cortex-a57. 7363 * As of GCC 4.8.4 a workaround for the ARM Cortex-A53 erratum 835769 7364 has been added and can be enabled by giving the 7365 -mfix-cortex-a53-835769 option. Alternatively it can be enabled by 7366 default by configuring GCC with the --enable-fix-cortex-a53-835769 7367 option. 7368 7369 ARM 7370 7371 * Initial support has been added for the AArch32 extensions defined 7372 in the ARMv8 architecture. 7373 * Code generation improvements for the Cortex-A7 and Cortex-A15 CPUs. 7374 * A new option, -mcpu=marvell-pj4, has been added to generate code 7375 for the Marvell PJ4 processor. 7376 * The compiler can now automatically generate the VFMA, VFMS, REVSH 7377 and REV16 instructions. 7378 * A new vectorizer cost model for Advanced SIMD configurations to 7379 improve the auto-vectorization strategies used. 7380 * The scheduler now takes into account the number of live registers 7381 to reduce the amount of spilling that can occur. This should 7382 improve code performance in large functions. The limit can be 7383 removed by using the option -fno-sched-pressure. 7384 * Improvements have been made to the Marvell iWMMX code generation 7385 and support for the iWMMX2 SIMD unit has been added. The option 7386 -mcpu=iwmmxt2 can be used to enable code generation for the latter. 7387 * A number of code generation improvements for Thumb2 to reduce code 7388 size when compiling for the M-profile processors. 7389 * The RTEMS (arm-rtems) port has been updated to use the EABI. 7390 * Code generation support for the old FPA and Maverick floating-point 7391 architectures has been removed. Ports that previously relied on 7392 these features have also been removed. This includes the targets: 7393 + arm*-*-linux-gnu (use arm*-*-linux-gnueabi) 7394 + arm*-*-elf (use arm*-*-eabi) 7395 + arm*-*-uclinux* (use arm*-*-uclinux*eabi) 7396 + arm*-*-ecos-elf (no alternative) 7397 + arm*-*-freebsd (no alternative) 7398 + arm*-wince-pe* (no alternative). 7399 7400 AVR 7401 7402 * Support for the "Embedded C" fixed-point has been added. For 7403 details, see the [28]GCC wiki and the [29]user manual. The support 7404 is not complete. 7405 * A new print modifier %r for register operands in inline assembler 7406 is supported. It will print the raw register number without the 7407 register prefix 'r': 7408 /* Return the most significant byte of 'val', a 64-bit value. */ 7409 7410 unsigned char msb (long long val) 7411 { 7412 unsigned char c; 7413 __asm__ ("mov %0, %r1+7" : "=r" (c) : "r" (val)); 7414 return c; 7415 } 7416 The inline assembler in this example will generate code like 7417 mov r24, 8+7 7418 provided c is allocated to R24 and val is allocated to R8...R15. 7419 This works because the GNU assembler accepts plain register numbers 7420 without register prefix. 7421 * Static initializers with 3-byte symbols are supported now: 7422 extern const __memx char foo; 7423 const __memx void *pfoo = &foo; 7424 This requires at least Binutils 2.23. 7425 7426 IA-32/x86-64 7427 7428 * Allow -mpreferred-stack-boundary=3 for the x86-64 architecture with 7429 SSE extensions disabled. Since the x86-64 ABI requires 16 byte 7430 stack alignment, this is ABI incompatible and intended to be used 7431 in controlled environments where stack space is an important 7432 limitation. This option will lead to wrong code when functions 7433 compiled with 16 byte stack alignment (such as functions from a 7434 standard library) are called with misaligned stack. In this case, 7435 SSE instructions may lead to misaligned memory access traps. In 7436 addition, variable arguments will be handled incorrectly for 16 7437 byte aligned objects (including x87 long double and __int128), 7438 leading to wrong results. You must build all modules with 7439 -mpreferred-stack-boundary=3, including any libraries. This 7440 includes the system libraries and startup modules. 7441 * Support for the new Intel processor codename Broadwell with RDSEED, 7442 ADCX, ADOX, PREFETCHW is available through -madx, -mprfchw, 7443 -mrdseed command-line options. 7444 * Support for the Intel RTM and HLE intrinsics, built-in functions 7445 and code generation is available via -mrtm and -mhle. 7446 * Support for the Intel FXSR, XSAVE and XSAVEOPT instruction sets. 7447 Intrinsics and built-in functions are available via -mfxsr, -mxsave 7448 and -mxsaveopt respectively. 7449 * New -maddress-mode=[short|long] options for x32. 7450 -maddress-mode=short overrides default 64-bit addresses to 32-bit 7451 by emitting the 0x67 address-size override prefix. This is the 7452 default address mode for x32. 7453 * New built-in functions to detect run-time CPU type and ISA: 7454 + A built-in function __builtin_cpu_is has been added to detect 7455 if the run-time CPU is of a particular type. It returns a 7456 positive integer on a match and zero otherwise. It accepts one 7457 string literal argument, the CPU name. For example, 7458 __builtin_cpu_is("westmere") returns a positive integer if the 7459 run-time CPU is an Intel Core i7 Westmere processor. Please 7460 refer to the [30]user manual for the list of valid CPU names 7461 recognized. 7462 + A built-in function __builtin_cpu_supports has been added to 7463 detect if the run-time CPU supports a particular ISA feature. 7464 It returns a positive integer on a match and zero otherwise. 7465 It accepts one string literal argument, the ISA feature. For 7466 example, __builtin_cpu_supports("ssse3") returns a positive 7467 integer if the run-time CPU supports SSSE3 instructions. 7468 Please refer to the [31]user manual for the list of valid ISA 7469 names recognized. 7470 Caveat: If these built-in functions are called before any static 7471 constructors are invoked, like during IFUNC initialization, then 7472 the CPU detection initialization must be explicitly run using this 7473 newly provided built-in function, __builtin_cpu_init. The 7474 initialization needs to be done only once. For example, this is how 7475 the invocation would look like inside an IFUNC initializer: 7476 static void (*some_ifunc_resolver(void))(void) 7477 { 7478 __builtin_cpu_init(); 7479 if (__builtin_cpu_is("amdfam10h") ... 7480 if (__builtin_cpu_supports("popcnt") ... 7481 } 7482 7483 * Function Multiversioning Support with G++: 7484 It is now possible to create multiple function versions each 7485 targeting a specific processor and/or ISA. Function versions have 7486 the same signature but different target attributes. For example, 7487 here is a program with function versions: 7488 __attribute__ ((target ("default"))) 7489 int foo(void) 7490 { 7491 return 1; 7492 } 7493 7494 __attribute__ ((target ("sse4.2"))) 7495 int foo(void) 7496 { 7497 return 2; 7498 } 7499 7500 int main (void) 7501 { 7502 int (*p) = &foo; 7503 assert ((*p)() == foo()); 7504 return 0; 7505 } 7506 7507 Please refer to this [32]wiki for more information. 7508 * The x86 back end has been improved to allow option -fschedule-insns 7509 to work reliably. This option can be used to schedule instructions 7510 better and leads to improved performace in certain cases. 7511 * Windows MinGW-w64 targets (*-w64-mingw*) require at least r5437 7512 from the Mingw-w64 trunk. 7513 * Support for new AMD family 15h processors (Steamroller core) is now 7514 available through the -march=bdver3 and -mtune=bdver3 options. 7515 * Support for new AMD family 16h processors (Jaguar core) is now 7516 available through the -march=btver2 and -mtune=btver2 options. 7517 7518 FRV 7519 7520 * This target now supports the -fstack-usage command-line option. 7521 7522 MIPS 7523 7524 * GCC can now generate code specifically for the R4700, Broadcom XLP 7525 and MIPS 34kn processors. The associated -march options are 7526 -march=r4700, -march=xlp and -march=34kn respectively. 7527 * GCC now generates better DSP code for MIPS 74k cores thanks to 7528 further scheduling optimizations. 7529 * The MIPS port now supports the -fstack-check option. 7530 * GCC now passes the -mmcu and -mno-mcu options to the assembler. 7531 * Previous versions of GCC would silently accept -fpic and -fPIC for 7532 -mno-abicalls targets like mips*-elf. This combination was not 7533 intended or supported, and did not generate position-independent 7534 code. GCC 4.8 now reports an error when this combination is used. 7535 7536 PowerPC / PowerPC64 / RS6000 7537 7538 * SVR4 configurations (GNU/Linux, FreeBSD, NetBSD) no longer save, 7539 restore or update the VRSAVE register by default. The respective 7540 operating systems manage the VRSAVE register directly. 7541 * Large TOC support has been added for AIX through the command line 7542 option -mcmodel=large. 7543 * Native Thread-Local Storage support has been added for AIX. 7544 * VMX (Altivec) and VSX instruction sets now are enabled implicitly 7545 when targetting processors that support those hardware features on 7546 AIX 6.1 and above. 7547 7548 RX 7549 7550 * This target will now issue a warning message whenever multiple fast 7551 interrupt handlers are found in the same compilation unit. This 7552 feature can be turned off by the new 7553 -mno-warn-multiple-fast-interrupts command-line option. 7554 7555 S/390, System z 7556 7557 * Support for the IBM zEnterprise zEC12 processor has been added. 7558 When using the -march=zEC12 option, the compiler will generate code 7559 making use of the following new instructions: 7560 + load and trap instructions 7561 + 2 new compare and trap instructions 7562 + rotate and insert selected bits - without CC clobber 7563 The -mtune=zEC12 option enables zEC12 specific instruction 7564 scheduling without making use of new instructions. 7565 * Register pressure sensitive instruction scheduling is enabled by 7566 default. 7567 * The ifunc function attribute is enabled by default. 7568 * memcpy and memcmp invokations on big memory chunks or with run time 7569 lengths are not generated inline anymore when tuning for z10 or 7570 higher. The purpose is to make use of the IFUNC optimized versions 7571 in Glibc. 7572 7573 SH 7574 7575 * The default alignment settings have been reduced to be less 7576 aggressive. This results in more compact code for optimization 7577 levels other than -Os. 7578 * Improved support for the __atomic built-in functions: 7579 + A new option -matomic-model=model selects the model for the 7580 generated atomic sequences. The following models are 7581 supported: 7582 7583 soft-gusa 7584 Software gUSA sequences (SH3* and SH4* only). On 7585 SH4A targets this will now also partially utilize 7586 the movco.l and movli.l instructions. This is the 7587 default when the target is sh3*-*-linux* or 7588 sh4*-*-linux*. 7589 7590 hard-llcs 7591 Hardware movco.l / movli.l sequences (SH4A only). 7592 7593 soft-tcb 7594 Software thread control block sequences. 7595 7596 soft-imask 7597 Software interrupt flipping sequences (privileged 7598 mode only). This is the default when the target is 7599 sh1*-*-linux* or sh2*-*-linux*. 7600 7601 none 7602 Generates function calls to the respective __atomic 7603 built-in functions. This is the default for SH64 7604 targets or when the target is not sh*-*-linux*. 7605 7606 + The option -msoft-atomic has been deprecated. It is now an 7607 alias for -matomic-model=soft-gusa. 7608 + A new option -mtas makes the compiler generate the tas.b 7609 instruction for the __atomic_test_and_set built-in function 7610 regardless of the selected atomic model. 7611 + The __sync functions in libgcc now reflect the selected atomic 7612 model when building the toolchain. 7613 * Added support for the mov.b and mov.w instructions with 7614 displacement addressing. 7615 * Added support for the SH2A instructions movu.b and movu.w. 7616 * Various improvements to code generated for integer arithmetic. 7617 * Improvements to conditional branches and code that involves the T 7618 bit. A new option -mzdcbranch tells the compiler to favor 7619 zero-displacement branches. This is enabled by default for SH4* 7620 targets. 7621 * The pref instruction will now be emitted by the __builtin_prefetch 7622 built-in function for SH3* targets. 7623 * The fmac instruction will now be emitted by the fmaf standard 7624 function and the __builtin_fmaf built-in function. 7625 * The -mfused-madd option has been deprecated in favor of the 7626 machine-independent -ffp-contract option. Notice that the fmac 7627 instruction will now be generated by default for expressions like a 7628 * b + c. This is due to the compiler default setting 7629 -ffp-contract=fast. 7630 * Added new options -mfsrra and -mfsca to allow the compiler using 7631 the fsrra and fsca instructions on targets other than SH4A (where 7632 they are already enabled by default). 7633 * Added support for the __builtin_bswap32 built-in function. It is 7634 now expanded as a sequence of swap.b and swap.w instructions 7635 instead of a library function call. 7636 * The behavior of the -mieee option has been fixed and the negative 7637 form -mno-ieee has been added to control the IEEE conformance of 7638 floating point comparisons. By default -mieee is now enabled and 7639 the option -ffinite-math-only implicitly sets -mno-ieee. 7640 * Added support for the built-in functions __builtin_thread_pointer 7641 and __builtin_set_thread_pointer. This assumes that GBR is used to 7642 hold the thread pointer of the current thread. Memory loads and 7643 stores relative to the address returned by __builtin_thread_pointer 7644 will now also utilize GBR based displacement address modes. 7645 * The -mdiv= option for targets other than SHmedia has been fixed and 7646 documented. 7647 7648 SPARC 7649 7650 * Added optimized instruction scheduling for Niagara4. 7651 7652 TILE-Gx 7653 7654 * Added support for the -mcmodel=MODEL command-line option. The 7655 models supported are small and large. 7656 7657 V850 7658 7659 * This target now supports the E3V5 architecture via the use of the 7660 new -mv850e3v5 command-line option. It also has experimental 7661 support for the e3v5 LOOP instruction which can be enabled via the 7662 new -mloop command-line option. 7663 7664 XStormy16 7665 7666 * This target now supports the -fstack-usage command-line option. 7667 7668 Operating Systems 7669 7670 OpenBSD 7671 7672 * Support for OpenBSD/amd64 (x86_64-*-openbsd*) has been added and 7673 support for OpenBSD/i386 (i386-*-openbsd*) has been rejuvenated. 7674 7675 Windows (Cygwin) 7676 7677 * Executables are now linked against shared libgcc by default. The 7678 previous default was to link statically, which can still be done by 7679 explicitly specifying -static or static-libgcc on the command line. 7680 However it is strongly advised against, as it will cause problems 7681 for any application that makes use of DLLs compiled by GCC. It 7682 should be alright for a monolithic stand-alone application that 7683 only links against the Windows DLLs, but offers little or no 7684 benefit. 7685 7686 GCC 4.8.1 7687 7688 This is the [33]list of problem reports (PRs) from GCC's bug tracking 7689 system that are known to be fixed in the 4.8.1 release. This list might 7690 not be complete (that is, it is possible that some PRs that have been 7691 fixed are not listed here). 7692 7693 The C++11 <chrono> std::chrono::system_clock and 7694 std::chrono::steady_clock classes have changed ABI in GCC 4.8.1, they 7695 both are now separate (never typedefs of each other), both use 7696 std::chrono::nanoseconds resolution, on most GNU/Linux configurations 7697 std::chrono::steady_clock is now finally monotonic, and both classes 7698 are mangled differently than in the previous GCC releases. 7699 std::chrono::system_clock::now() with std::chrono::microseconds resp. 7700 std::chrono::seconds resolution is still exported for backwards 7701 compatibility with default configured libstdc++. Note that libstdc++ 7702 configured with --enable-libstdcxx-time= used to be ABI incompatible 7703 with default configured libstdc++ for those two classes and no ABI 7704 compatibility can be offered for those configurations, so any C++11 7705 code that uses those classes and has been compiled and linked against 7706 libstdc++ configured with the non-default --enable-libstdcxx-time= 7707 configuration option needs to be recompiled. 7708 7709 GCC 4.8.2 7710 7711 This is the [34]list of problem reports (PRs) from GCC's bug tracking 7712 system that are known to be fixed in the 4.8.2 release. This list might 7713 not be complete (that is, it is possible that some PRs that have been 7714 fixed are not listed here). 7715 7716 GCC 4.8.3 7717 7718 This is the [35]list of problem reports (PRs) from GCC's bug tracking 7719 system that are known to be fixed in the 4.8.3 release. This list might 7720 not be complete (that is, it is possible that some PRs that have been 7721 fixed are not listed here). 7722 7723 Support for the new powerpc64le-linux platform has been added. It 7724 defaults to generating code that conforms to the ELFV2 ABI. 7725 7726 GCC 4.8.4 7727 7728 This is the [36]list of problem reports (PRs) from GCC's bug tracking 7729 system that are known to be fixed in the 4.8.4 release. This list might 7730 not be complete (that is, it is possible that some PRs that have been 7731 fixed are not listed here). 7732 7733 GCC 4.8.5 7734 7735 This is the [37]list of problem reports (PRs) from GCC's bug tracking 7736 system that are known to be fixed in the 4.8.5 release. This list might 7737 not be complete (that is, it is possible that some PRs that have been 7738 fixed are not listed here). 7739 7740 7741 For questions related to the use of GCC, please consult these web 7742 pages and the [38]GCC manuals. If that fails, the 7743 [39]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 7744 web pages and the development of GCC are welcome on our developer 7745 list at [40]gcc (a] gcc.gnu.org. All of [41]our lists have public 7746 archives. 7747 7748 Copyright (C) [42]Free Software Foundation, Inc. Verbatim copying and 7749 distribution of this entire article is permitted in any medium, 7750 provided this notice is preserved. 7751 7752 These pages are [43]maintained by the GCC team. Last modified 7753 2022-11-05. 7754 7755 References 7756 7757 1. https://gcc.gnu.org/wiki/cxx-conversion 7758 2. ftp://gcc.gnu.org/pub/gcc/infrastructure/ 7759 3. http://www.nongnu.org/avr-libc/ 7760 4. https://gcc.gnu.org/PR54461 7761 5. https://gcc.gnu.org/gcc-4.8/porting_to.html 7762 6. https://github.com/google/sanitizers 7763 7. https://code.google.com/archive/p/data-race-test/wikis/ThreadSanitizer.wiki 7764 8. https://lkml.org/lkml/2006/11/28/239 7765 9. http://gcc.gnu.org/gcc-4.8/cxx0x_status.html 7766 10. http://gcc.gnu.org/gcc-4.8/cxx0x_status.html 7767 11. http://gcc.gnu.org/gcc-4.8/cxx0x_status.html 7768 12. https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3276.pdf 7769 13. http://gcc.gnu.org/gcc-4.8/cxx0x_status.html 7770 14. https://www.open-std.org/JTC1/SC22/WG21/docs/papers/2012/n3386.html 7771 15. http://gcc.gnu.org/projects/cxx1y.html 7772 16. https://gcc.gnu.org/onlinedocs/gcc-4.8.4/libstdc++/manual/manual/status.html#status.iso.2011 7773 17. https://gcc.gnu.org/onlinedocs/gfortran/BACKTRACE.html 7774 18. https://gcc.gnu.org/onlinedocs/gfortran/Error-and-Warning-Options.html 7775 19. https://gcc.gnu.org/onlinedocs/gfortran/Error-and-Warning-Options.html 7776 20. https://gcc.gnu.org/onlinedocs/gfortran/Code-Gen-Options.html 7777 21. https://gcc.gnu.org/onlinedocs/gfortran/Error-and-Warning-Options.html 7778 22. https://gcc.gnu.org/onlinedocs/gfortran/Error-and-Warning-Options.html 7779 23. https://gcc.gnu.org/onlinedocs/gfortran/TMPDIR.html 7780 24. https://gcc.gnu.org/wiki/Fortran2003Status 7781 25. https://gcc.gnu.org/wiki/TS29113Status 7782 26. https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=libgfortran/libgfortran.h 7783 27. https://chasm-interop.sourceforge.net/ 7784 28. https://gcc.gnu.org/wiki/avr-gcc#Fixed-Point_Support 7785 29. https://gcc.gnu.org/onlinedocs/gcc/Fixed-Point.html 7786 30. https://gcc.gnu.org/onlinedocs/gcc/x86-Built-in-Functions.html 7787 31. https://gcc.gnu.org/onlinedocs/gcc/x86-Built-in-Functions.html 7788 32. https://gcc.gnu.org/wiki/FunctionMultiVersioning 7789 33. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.8.1 7790 34. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.8.2 7791 35. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.8.3 7792 36. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.8.4 7793 37. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.8.5 7794 38. https://gcc.gnu.org/onlinedocs/ 7795 39. mailto:gcc-help (a] gcc.gnu.org 7796 40. mailto:gcc (a] gcc.gnu.org 7797 41. https://gcc.gnu.org/lists.html 7798 42. https://www.fsf.org/ 7799 43. https://gcc.gnu.org/about.html 7800 ====================================================================== 7801 http://gcc.gnu.org/gcc-4.7/index.html 7802 7803 GCC 4.7 Release Series 7804 7805 (This release series is no longer supported.) 7806 7807 June 12, 2014 7808 7809 The [1]GNU project and the GCC developers are pleased to announce the 7810 release of GCC 4.7.4. 7811 7812 This release is a bug-fix release, containing fixes for regressions in 7813 GCC 4.7.3 relative to previous releases of GCC. 7814 7815 Release History 7816 7817 GCC 4.7.4 7818 June 12, 2014 ([2]changes, [3]documentation) 7819 7820 GCC 4.7.3 7821 April 11, 2013 ([4]changes, [5]documentation) 7822 7823 GCC 4.7.2 7824 September 20, 2012 ([6]changes, [7]documentation) 7825 7826 GCC 4.7.1 7827 June 14, 2012 ([8]changes, [9]documentation) 7828 7829 GCC 4.7.0 7830 March 22, 2012 ([10]changes, [11]documentation) 7831 7832 References and Acknowledgements 7833 7834 GCC used to stand for the GNU C Compiler, but since the compiler 7835 supports several other languages aside from C, it now stands for the 7836 GNU Compiler Collection. 7837 7838 A list of [12]successful builds is updated as new information becomes 7839 available. 7840 7841 The GCC developers would like to thank the numerous people that have 7842 contributed new features, improvements, bug fixes, and other changes as 7843 well as test results to GCC. This [13]amazing group of volunteers is 7844 what makes GCC successful. 7845 7846 For additional information about GCC please refer to the [14]GCC 7847 project web site or contact the [15]GCC development mailing list. 7848 7849 To obtain GCC please use [16]our mirror sites or [17]our version 7850 control system. 7851 7852 7853 For questions related to the use of GCC, please consult these web 7854 pages and the [18]GCC manuals. If that fails, the 7855 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 7856 web pages and the development of GCC are welcome on our developer 7857 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 7858 archives. 7859 7860 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 7861 distribution of this entire article is permitted in any medium, 7862 provided this notice is preserved. 7863 7864 These pages are [23]maintained by the GCC team. Last modified 7865 2022-10-26. 7866 7867 References 7868 7869 1. http://www.gnu.org/ 7870 2. http://gcc.gnu.org/gcc-4.7/changes.html 7871 3. https://gcc.gnu.org/onlinedocs/4.7.4/ 7872 4. http://gcc.gnu.org/gcc-4.7/changes.html 7873 5. https://gcc.gnu.org/onlinedocs/4.7.3/ 7874 6. http://gcc.gnu.org/gcc-4.7/changes.html 7875 7. https://gcc.gnu.org/onlinedocs/4.7.2/ 7876 8. http://gcc.gnu.org/gcc-4.7/changes.html 7877 9. https://gcc.gnu.org/onlinedocs/4.7.1/ 7878 10. http://gcc.gnu.org/gcc-4.7/changes.html 7879 11. https://gcc.gnu.org/onlinedocs/4.7.0/ 7880 12. http://gcc.gnu.org/gcc-4.7/buildstat.html 7881 13. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 7882 14. http://gcc.gnu.org/index.html 7883 15. mailto:gcc (a] gcc.gnu.org 7884 16. http://gcc.gnu.org/mirrors.html 7885 17. http://gcc.gnu.org/git.html 7886 18. https://gcc.gnu.org/onlinedocs/ 7887 19. mailto:gcc-help (a] gcc.gnu.org 7888 20. mailto:gcc (a] gcc.gnu.org 7889 21. https://gcc.gnu.org/lists.html 7890 22. https://www.fsf.org/ 7891 23. https://gcc.gnu.org/about.html 7892 ====================================================================== 7893 http://gcc.gnu.org/gcc-4.7/changes.html 7894 7895 GCC 4.7 Release Series 7896 Changes, New Features, and Fixes 7897 7898 Caveats 7899 7900 * The -fconserve-space flag has been deprecated. The flag had no 7901 effect for most targets: only targets without a global .bss section 7902 and without support for switchable sections. Furthermore, the flag 7903 only had an effect for G++, where it could result in wrong 7904 semantics (please refer to the GCC manual for further details). The 7905 flag will be removed in GCC 4.8 7906 * Support for a number of older systems and recently unmaintained or 7907 untested target ports of GCC has been declared obsolete in GCC 4.7. 7908 Unless there is activity to revive them, the next release of GCC 7909 will have their sources permanently removed. 7910 All GCC ports for the following processor architectures have been 7911 declared obsolete: 7912 + picoChip (picochip-*) 7913 The following ports for individual systems on particular 7914 architectures have been obsoleted: 7915 + IRIX 6.5 (mips-sgi-irix6.5) 7916 + MIPS OpenBSD (mips*-*-openbsd*) 7917 + Solaris 8 (*-*-solaris2.8). Details can be found in the 7918 [1]announcement. 7919 + Tru64 UNIX V5.1 (alpha*-dec-osf5.1*) 7920 * On ARM, when compiling for ARMv6 (but not ARMv6-M), ARMv7-A, 7921 ARMv7-R, or ARMv7-M, the new option -munaligned-access is active by 7922 default, which for some sources generates code that accesses memory 7923 on unaligned addresses. This requires the kernel of those systems 7924 to enable such accesses (controlled by CP15 register c1, refer to 7925 ARM documentation). Alternatively, or for compatibility with 7926 kernels where unaligned accesses are not supported, all code has to 7927 be compiled with -mno-unaligned-access. Upstream Linux kernel 7928 releases have automatically and unconditionally supported unaligned 7929 accesses as emitted by GCC due to this option being active since 7930 version 2.6.28. 7931 * Support on ARM for the legacy floating-point accelerator (FPA) and 7932 the mixed-endian floating-point format that it used has been 7933 obsoleted. The ports that still use this format have been obsoleted 7934 as well. Many legacy ARM ports already provide an alternative that 7935 uses the VFP floating-point format. The obsolete ports will be 7936 deleted in the next release. 7937 The obsolete ports with alternatives are: 7938 + arm*-*-rtems (use arm*-*-rtemseabi) 7939 + arm*-*-linux-gnu (use arm*-*-linux-gnueabi) 7940 + arm*-*-elf (use arm*-*-eabi) 7941 + arm*-*-uclinux* (use arm*-*-uclinux*eabi) 7942 Note, however, that these alternatives are not binary compatible 7943 with their legacy counterparts (although some can support running 7944 legacy applications). 7945 The obsolete ports that currently lack a modern alternative are: 7946 + arm*-*-ecos-elf 7947 + arm*-*-freebsd 7948 + arm*-wince-pe* 7949 New ports that support more recent versions of the architecture are 7950 welcome. 7951 * Support for the Maverick co-processor on ARM has been obsoleted. 7952 Code to support it will be deleted in the next release. 7953 * Support has been removed for Unix International threads on Solaris 7954 2, so the --enable-threads=solaris configure option and the 7955 -threads compiler option don't work any longer. 7956 * Support has been removed for the Solaris BSD Compatibility Package, 7957 which lives in /usr/ucbinclude and /usr/ucblib. It has been removed 7958 from Solaris 11, and was only intended as a migration aid from 7959 SunOS 4 to SunOS 5. The -compat-bsd compiler option is not 7960 recognized any longer. 7961 * The AVR port's libgcc has been improved and its multilib structure 7962 has been enhanced. As a result, all objects contributing to an 7963 application must either be compiled with GCC versions up to 4.6.x 7964 or with GCC versions 4.7.1 or later. If the compiler is used with 7965 AVR Libc, you need a version that supports the new layout, i.e. 7966 implements [2]#35407. 7967 * The AVR port's -mshort-calls command-line option has been 7968 deprecated. It will be removed in the GCC 4.8 release. See -mrelax 7969 for a replacement. 7970 * The AVR port only references startup code that clears .bss and the 7971 common section resp. initializes the .data and .rodata section 7972 provided respective sections (or subsections thereof) are not 7973 empty, see [3]PR18145. Applications that put all static storage 7974 objects into non-standard sections and / or define all static 7975 storage objects in assembler modules, must reference __do_clear_bss 7976 resp. __do_copy_data by hand or undefine the symbol(s) by means of 7977 -Wl,-u,__do_clear_bss resp. -Wl,-u,__do_copy_data. 7978 * The ARM port's -mwords-little-endian option has been deprecated. It 7979 will be removed in a future release. 7980 * Support has been removed for the NetWare x86 configuration 7981 obsoleted in GCC 4.6. 7982 * It is no longer possible to use the "l" constraint in MIPS16 asm 7983 statements. 7984 * GCC versions 4.7.0 and 4.7.1 had changes to the C++ standard 7985 library which affected the ABI in C++11 mode: a data member was 7986 added to std::list changing its size and altering the definitions 7987 of some member functions, and std::pair's move constructor was 7988 non-trivial which altered the calling convention for functions with 7989 std::pair arguments or return types. The ABI incompatibilities have 7990 been fixed for GCC version 4.7.2 but as a result C++11 code 7991 compiled with GCC 4.7.0 or 4.7.1 may be incompatible with C++11 7992 code compiled with different GCC versions and with C++98/C++03 code 7993 compiled with any version. 7994 * On ARM, a bug has been fixed in GCC's implementation of the AAPCS 7995 rules for the layout of vectors that could lead to wrong code being 7996 generated. Vectors larger than 8 bytes in size are now by default 7997 aligned to an 8-byte boundary. This is an ABI change: code that 7998 makes explicit use of vector types may be incompatible with binary 7999 objects built with older versions of GCC. Auto-vectorized code is 8000 not affected by this change. (This change affects GCC versions 8001 4.7.2 and later.) 8002 * More information on porting to GCC 4.7 from previous versions of 8003 GCC can be found in the [4]porting guide for this release. 8004 8005 General Optimizer Improvements 8006 8007 * Support for a new parameter --param case-values-threshold=n was 8008 added to allow users to control the cutoff between doing switch 8009 statements as a series of if statements and using a jump table. 8010 * Link-time optimization (LTO) improvements: 8011 + Improved scalability and reduced memory usage. Link time 8012 optimization of Firefox now requires 3GB of RAM on a 64-bit 8013 system, while over 8GB was needed previously. Linking time has 8014 been improved, too. The serial stage of linking Firefox has 8015 been sped up by about a factor of 10. 8016 + Reduced size of object files and temporary storage used during 8017 linking. 8018 + Streaming performance (both outbound and inbound) has been 8019 improved. 8020 + ld -r is now supported with LTO. 8021 + Several bug fixes, especially in symbol table handling and 8022 merging. 8023 * Interprocedural optimization improvements: 8024 + Heuristics now take into account that after inlining code will 8025 be optimized out because of known values (or properties) of 8026 function parameters. For example: 8027 void foo(int a) 8028 { 8029 if (a > 10) 8030 ... huge code ... 8031 } 8032 void bar (void) 8033 { 8034 foo (0); 8035 } 8036 8037 The call of foo will be inlined into bar even when optimizing 8038 for code size. Constructs based on __builtin_constant_p are 8039 now understood by the inliner and code size estimates are 8040 evaluated a lot more realistically. 8041 + The representation of C++ virtual thunks and aliases (both 8042 implicit and defined via the alias attribute) has been 8043 re-engineered. Aliases no longer pose optimization barriers 8044 and calls to an alias can be inlined and otherwise optimized. 8045 + The inter-procedural constant propagation pass has been 8046 rewritten. It now performs generic function specialization. 8047 For example when compiling the following: 8048 void foo(bool flag) 8049 { 8050 if (flag) 8051 ... do something ... 8052 else 8053 ... do something else ... 8054 } 8055 void bar (void) 8056 { 8057 foo (false); 8058 foo (true); 8059 foo (false); 8060 foo (true); 8061 foo (false); 8062 foo (true); 8063 } 8064 8065 GCC will now produce two copies of foo. One with flag being 8066 true, while other with flag being false. This leads to 8067 performance improvements previously possible only by inlining 8068 all calls. Cloning causes a lot less code size growth. 8069 * A string length optimization pass has been added. It attempts to 8070 track string lengths and optimize various standard C string 8071 functions like strlen, strchr, strcpy, strcat, stpcpy and their 8072 _FORTIFY_SOURCE counterparts into faster alternatives. This pass is 8073 enabled by default at -O2 or above, unless optimizing for size, and 8074 can be disabled by the -fno-optimize-strlen option. The pass can 8075 e.g. optimize 8076 char *bar (const char *a) 8077 { 8078 size_t l = strlen (a) + 2; 8079 char *p = malloc (l); if (p == NULL) return p; 8080 strcpy (p, a); strcat (p, "/"); return p; 8081 } 8082 8083 into: 8084 char *bar (const char *a) 8085 { 8086 size_t tmp = strlen (a); 8087 char *p = malloc (tmp + 2); if (p == NULL) return p; 8088 memcpy (p, a, tmp); memcpy (p + tmp, "/", 2); return p; 8089 } 8090 8091 or for hosted compilations where stpcpy is available in the runtime 8092 and headers provide its prototype, e.g. 8093 void foo (char *a, const char *b, const char *c, const char *d) 8094 { 8095 strcpy (a, b); strcat (a, c); strcat (a, d); 8096 } 8097 8098 can be optimized into: 8099 void foo (char *a, const char *b, const char *c, const char *d) 8100 { 8101 strcpy (stpcpy (stpcpy (a, b), c), d); 8102 } 8103 8104 New Languages and Language specific improvements 8105 8106 * Version 3.1 of the OpenMP specification is now supported for the C, 8107 C++, and Fortran compilers. 8108 8109 Ada 8110 8111 * The command-line option -feliminate-unused-debug-types has been 8112 re-enabled by default, as it is for the other languages, leading to 8113 a reduction in debug info size of 12.5% and more for relevant 8114 cases, as well as to a small compilation speedup. 8115 8116 C family 8117 8118 * A new built-in, __builtin_assume_aligned, has been added, through 8119 which the compiler can be hinted about pointer alignment and can 8120 use it to improve generated code. 8121 * A new warning option -Wunused-local-typedefs was added for C, C++, 8122 Objective-C and Objective-C++. This warning diagnoses typedefs 8123 locally defined in a function, and otherwise not used. 8124 * A new experimental command-line option -ftrack-macro-expansion was 8125 added for C, C++, Objective-C, Objective-C++ and Fortran. It allows 8126 the compiler to emit diagnostic about the current macro expansion 8127 stack when a compilation error occurs in a macro expansion. 8128 * Experimental support for transactional memory has been added. It 8129 includes support in the compiler, as well as a supporting runtime 8130 library called libitm. To compile code with transactional memory 8131 constructs, use the -fgnu-tm option. 8132 Support is currently available for Alpha, ARM, PowerPC, SH, SPARC, 8133 and 32-bit/64-bit x86 platforms. 8134 For more details on transactional memory see [5]the GCC WiKi. 8135 * Support for atomic operations specifying the C++11/C11 memory model 8136 has been added. These new __atomic routines replace the existing 8137 __sync built-in routines. 8138 Atomic support is also available for memory blocks. Lock-free 8139 instructions will be used if a memory block is the same size and 8140 alignment as a supported integer type. Atomic operations which do 8141 not have lock-free support are left as function calls. A set of 8142 library functions is available on the GCC atomic wiki in the 8143 "External Atomics Library" section. 8144 For more details on the memory models and features, see the 8145 [6]atomic wiki. 8146 * When a binary operation is performed on vector types and one of the 8147 operands is a uniform vector, it is possible to replace the vector 8148 with the generating element. For example: 8149 typedef int v4si __attribute__ ((vector_size (16))); 8150 v4si res, a = {1,2,3,4}; 8151 int x; 8152 8153 res = 2 + a; /* means {2,2,2,2} + a */ 8154 res = a - x; /* means a - {x,x,x,x} */ 8155 8156 C 8157 8158 * There is support for some more features from the C11 revision of 8159 the ISO C standard. GCC now accepts the options -std=c11 and 8160 -std=gnu11, in addition to the previous -std=c1x and -std=gnu1x. 8161 + Unicode strings (previously supported only with options such 8162 as -std=gnu11, now supported with -std=c11), and the 8163 predefined macros __STDC_UTF_16__ and __STDC_UTF_32__. 8164 + Nonreturning functions (_Noreturn and <stdnoreturn.h>). 8165 + Alignment support (_Alignas, _Alignof, max_align_t, 8166 <stdalign.h>). 8167 + A built-in function __builtin_complex is provided to support C 8168 library implementation of the CMPLX family of macros. 8169 8170 C++ 8171 8172 * G++ now accepts the -std=c++11, -std=gnu++11, and -Wc++11-compat 8173 options, which are equivalent to -std=c++0x, -std=gnu++0x, and 8174 -Wc++0x-compat, respectively. 8175 * G++ now implements [7]C++11 extended friend syntax: 8176 8177 template<class W> 8178 class Q 8179 { 8180 static const int I = 2; 8181 public: 8182 friend W; 8183 }; 8184 8185 struct B 8186 { 8187 int ar[Q<B>::I]; 8188 }; 8189 8190 * Thanks to Ville Voutilainen, G++ now implements [8]C++11 explicit 8191 override control. 8192 8193 struct B { 8194 virtual void f() const final; 8195 virtual void f(int); 8196 }; 8197 8198 struct D : B { 8199 void f() const; // error: D::f attempts to override final B::f 8200 void f(long) override; // error: doesn't override anything 8201 void f(int) override; // ok 8202 }; 8203 8204 struct E final { }; 8205 struct F: E { }; // error: deriving from final class 8206 8207 * G++ now implements [9]C++11 non-static data member initializers. 8208 8209 struct A { 8210 int i = 42; 8211 } a; // initializes a.i to 42 8212 8213 * Thanks to Ed Smith-Rowland, G++ now implements [10]C++11 8214 user-defined literals. 8215 8216 // Not actually a good approximation. :) 8217 constexpr long double operator"" _degrees (long double d) { return d * 0.0175; } 8218 long double pi = 180.0_degrees; 8219 8220 * G++ now implements [11]C++11 alias-declarations. 8221 8222 template <class T> using Ptr = T*; 8223 Ptr<int> ip; // decltype(ip) is int* 8224 8225 * Thanks to Ville Voutilainen and Pedro Lamaro, G++ now implements 8226 [12]C++11 delegating constructors. 8227 8228 struct A { 8229 A(int); 8230 A(): A(42) { } // delegate to the A(int) constructor 8231 }; 8232 8233 * G++ now fully implements C++11 atomic classes rather than just 8234 integer derived classes. 8235 8236 class POD { 8237 int a; 8238 int b; 8239 }; 8240 std::atomic<POD> my_atomic_POD; 8241 8242 * G++ now sets the predefined macro __cplusplus to the correct value, 8243 199711L for C++98/03, and 201103L for C++11. 8244 * G++ now correctly implements the two-phase lookup rules such that 8245 an unqualified name used in a template must have an appropriate 8246 declaration found either in scope at the point of definition of the 8247 template or by argument-dependent lookup at the point of 8248 instantiation. As a result, code that relies on a second 8249 unqualified lookup at the point of instantiation to find functions 8250 declared after the template or in dependent bases will be rejected. 8251 The compiler will suggest ways to fix affected code, and using the 8252 -fpermissive compiler flag will allow the code to compile with a 8253 warning. 8254 8255 template <class T> 8256 void f() { g(T()); } // error, g(int) not found by argument-dependent lookup 8257 void g(int) { } // fix by moving this declaration before the declaration of f 8258 8259 template <class T> 8260 struct A: T { 8261 // error, B::g(B) not found by argument-dependent lookup 8262 void f() { g(T()); } // fix by using this->g or A::g 8263 }; 8264 8265 struct B { void g(B); }; 8266 8267 int main() 8268 { 8269 f<int>(); 8270 A<B>().f(); 8271 } 8272 8273 * G++ now properly re-uses stack space allocated for temporary 8274 objects when their lifetime ends, which can significantly lower 8275 stack consumption for some C++ functions. As a result of this, some 8276 code with undefined behavior will now break: 8277 8278 const int &f(const int &i) { return i; } 8279 .... 8280 const int &x = f(1); 8281 const int &y = f(2); 8282 8283 Here, x refers to the temporary allocated to hold the 1 argument, 8284 which only lives until the end of the initialization; it 8285 immediately becomes a dangling reference. So the next statement 8286 re-uses the stack slot to hold the 2 argument, and users of x get 8287 that value instead. 8288 Note that this should not cause any change of behavior for 8289 temporaries of types with non-trivial destructors, as they are 8290 already destroyed at end of full-expression; the change is that now 8291 the storage is released as well. 8292 * A new command-line option -Wdelete-non-virtual-dtor has been added 8293 to warn when delete is used to destroy an instance of a class which 8294 has virtual functions and non-virtual destructor. It is unsafe to 8295 delete an instance of a derived class through a pointer to a base 8296 class if the base class does not have a virtual destructor. This 8297 warning is enabled by -Wall. 8298 * A new command-line option -Wzero-as-null-pointer-constant has been 8299 added to warn when a literal '0' is used as null pointer constant. 8300 It can be useful to facilitate the conversion to nullptr in C++11. 8301 * As per C++98, access-declarations are now deprecated by G++. 8302 Using-declarations are to be used instead. Furthermore, some 8303 efforts have been made to improve the support of class scope 8304 using-declarations. In particular, using-declarations referring to 8305 a dependent type now work as expected ([13]bug c++/14258). 8306 * The ELF symbol visibility of a template instantiation is now 8307 properly constrained by the visibility of its template arguments 8308 ([14]bug c++/35688). 8309 8310 Runtime Library (libstdc++) 8311 8312 * [15]Improved experimental support for the new ISO C++ standard, 8313 C++11, including: 8314 + using noexcept in most of the library; 8315 + implementations of pointer_traits, allocator_traits and 8316 scoped_allocator_adaptor; 8317 + uses-allocator construction for tuple; 8318 + vector meets the allocator-aware container requirements; 8319 + replacing monotonic_clock with steady_clock; 8320 + enabling the thread support library on most POSIX targets; 8321 + many small improvements to conform to the FDIS. 8322 * Added --enable-clocale=newlib configure option. 8323 * Debug Mode iterators for unordered associative containers. 8324 * Avoid polluting the global namespace and do not include <unistd.h>. 8325 8326 Fortran 8327 8328 * The compile flag [16]-fstack-arrays has been added, which causes 8329 all local arrays to be put on stack memory. For some programs this 8330 will improve the performance significantly. If your program uses 8331 very large local arrays, it is possible that you will have to 8332 extend your runtime limits for stack memory. 8333 * The [17]-Ofast flag now also implies [18]-fno-protect-parens and 8334 [19]-fstack-arrays. 8335 * Front-end optimizations can now be selected by the 8336 [20]-ffrontend-optimize option and deselected by the 8337 -fno-frontend-optimize option. 8338 * When front-end optimization removes a function call, 8339 [21]-Wfunction-elimination warns about that. 8340 * When performing front-end-optimization, the 8341 [22]-faggressive-function-elimination option allows the removal of 8342 duplicate function calls even for impure functions. 8343 * The flag [23]-Wreal-q-constant has been added, which warns if 8344 floating-point literals have been specified using q (such as 8345 1.0q0); the q marker is now supported as a vendor extension to 8346 denote quad precision (REAL(16) or, if not available, REAL(10)). 8347 Consider using a kind parameter (such as in 1.0_qp) instead, which 8348 can be obtained via [24]SELECTED_REAL_KIND. 8349 * The GFORTRAN_USE_STDERR environment variable has been removed. GNU 8350 Fortran now always prints error messages to standard error. If you 8351 wish to redirect standard error, please consult the manual for your 8352 OS, shell, batch environment etc. as appropriate. 8353 * The -fdump-core option and GFORTRAN_ERROR_DUMPCORE environment 8354 variable have been removed. When encountering a serious error, 8355 gfortran will now always abort the program. Whether a core dump is 8356 generated depends on the user environment settings; see the ulimit 8357 -c setting for POSIX shells, limit coredumpsize for C shells, and 8358 the [25]WER user-mode dumps settings on Windows. 8359 * The [26]-fbacktrace option is now enabled by default. When 8360 encountering a fatal error, gfortran will attempt to print a 8361 backtrace to standard error before aborting. It can be disabled 8362 with -fno-backtrace. Note: On POSIX targets with the addr2line 8363 utility from GNU binutils, GNU Fortran can print a backtrace with 8364 function name, file name, line number information in addition to 8365 the addresses; otherwise only the addresses are printed. 8366 * [27]Fortran 2003: 8367 + Generic interface names which have the same name as derived 8368 types are now supported, which allows to write constructor 8369 functions. Note that Fortran does not support static 8370 constructor functions; only default initialization or an 8371 explicit structure-constructor initialization are available. 8372 + [28]Polymorphic (class) arrays are now supported. 8373 * [29]Fortran 2008: 8374 + Support for the DO CONCURRENT construct has been added, which 8375 allows the user to specify that individual loop iterations 8376 have no interdependencies. 8377 + [30]Coarrays: Full single-image support except for polymorphic 8378 coarrays. Additionally, preliminary support for multiple 8379 images via an MPI-based [31]coarray communication library has 8380 been added. Note: The library version is not yet usable as 8381 remote coarray access is not yet possible. 8382 * [32]TS 29113: 8383 + New flag [33]-std=f2008ts permits programs that are expected 8384 to conform to the Fortran 2008 standard and the draft 8385 Technical Specification (TS) 29113 on Further Interoperability 8386 of Fortran with C. 8387 + The OPTIONAL attribute is now allowed for dummy arguments of 8388 BIND(C) procedures. 8389 + The RANK intrinsic has been added. 8390 + The implementation of the ASYNCHRONOUS attribute in GCC is 8391 compatible with the candidate draft of TS 29113 (since GCC 8392 4.6). 8393 8394 Go 8395 8396 * GCC 4.7 implements the [34]Go 1 language standard. The library 8397 support in 4.7.0 is not quite complete, due to release timing. 8398 Release 4.7.1 includes complete support for Go 1. The Go library is 8399 from the Go 1.0.1 release. 8400 * Go has been tested on GNU/Linux and Solaris platforms. It may work 8401 on other platforms as well. 8402 8403 New Targets and Target Specific Improvements 8404 8405 ARM 8406 8407 * GCC now supports the Cortex-A7 processor implementing the v7-a 8408 version of the architecture using the option -mcpu=cortex-a7. 8409 * The default vector size in auto-vectorization for NEON is now 128 8410 bits. If vectorization fails thusly, the vectorizer tries again 8411 with 64-bit vectors. 8412 * A new option -mvectorize-with-neon-double was added to allow users 8413 to change the vector size to 64 bits. 8414 8415 AVR 8416 8417 * GCC now supports the XMEGA architecture. This requires GNU binutils 8418 2.22 or later. 8419 * Support for the [35]named address spaces __flash, __flash1, ..., 8420 __flash5 and __memx has been added. These address spaces locate 8421 read-only data in flash memory and allow reading from flash memory 8422 by means of ordinary C code, i.e. without the need of (inline) 8423 assembler code: 8424 8425 const __flash int values[] = { 42, 31 }; 8426 8427 int add_values (const __flash int *p, int i) 8428 { 8429 return values[i] + *p; 8430 } 8431 8432 * Support has been added for the AVR-specific configure option 8433 --with-avrlibc=yes in order to arrange for better integration of 8434 [36]AVR-Libc. This configure option is supported in avr-gcc 4.7.2 8435 and newer and will only take effect in non-RTEMS configurations. If 8436 avr-gcc is configured for RTEMS, the option will be ignored which 8437 is the same as specifying --with-avrlibc=no. See [37]PR54461 for 8438 more technical details. 8439 * Support for AVR-specific [38]built-in functions has been added. 8440 * Support has been added for the signed and unsigned 24-bit scalar 8441 integer types __int24 and __uint24. 8442 * New command-line options -maccumulate-args, -mbranch-cost=cost and 8443 -mstrict-X were added to allow better fine-tuning of code 8444 optimization. 8445 * The command-line option -fdata-sections now also takes affect on 8446 the section names of variables with the progmem attribute. 8447 * A new inline assembler print modifier %i to print a RAM address as 8448 I/O address has been added: 8449 8450 #include <avr/io.h> /* Port Definitions from AVR-LibC */ 8451 8452 void set_portb (uint8_t value) 8453 { 8454 asm volatile ("out %i0, %1" :: "n" (&PORTB), "r" (value) : "memory"); 8455 } 8456 8457 The offset between an I/O address and the RAM address for that I/O 8458 location is device-specific. This offset is taken into account when 8459 printing a RAM address with the %i modifier so that the address is 8460 suitable to be used as operand in an I/O command. The address must 8461 be a constant integer known at compile time. 8462 * The inline assembler constraint "R" to represent integers in the 8463 range -6 ... 5 has been removed without replacement. 8464 * Many optimizations to: 8465 + 64-bit integer arithmetic 8466 + Widening multiplication 8467 + Integer division by a constant 8468 + Avoid constant reloading in multi-byte instructions. 8469 + Micro-optimizations for special instruction sequences. 8470 + Generic built-in functions like __builtin_ffs*, 8471 __builtin_clz*, etc. 8472 + If-else decision trees generated by switch instructions 8473 + Merging of data located in flash memory 8474 + New libgcc variants for devices with 8-bit wide stack pointer 8475 + ... 8476 * Better documentation: 8477 + Handling of EIND and indirect jumps on devices with more than 8478 128 KiB of program memory. 8479 + Handling of the RAMPD, RAMPX, RAMPY and RAMPZ special function 8480 registers. 8481 + Function attributes OS_main and OS_task. 8482 + AVR-specific built-in macros. 8483 8484 C6X 8485 8486 * Support has been added for the Texas Instruments C6X family of 8487 processors. 8488 8489 CR16 8490 8491 * Support has been added for National Semiconductor's CR16 8492 architecture. 8493 8494 Epiphany 8495 8496 * Support has been added for Adapteva's Epiphany architecture. 8497 8498 IA-32/x86-64 8499 8500 * Support for Intel AVX2 intrinsics, built-in functions and code 8501 generation is available via -mavx2. 8502 * Support for Intel BMI2 intrinsics, built-in functions and code 8503 generation is available via -mbmi2. 8504 * Implementation and automatic generation of __builtin_clz* using the 8505 lzcnt instruction is available via -mlzcnt. 8506 * Support for Intel FMA3 intrinsics and code generation is available 8507 via -mfma. 8508 * A new -mfsgsbase command-line option is available that makes GCC 8509 generate new segment register read/write instructions through 8510 dedicated built-ins. 8511 * Support for the new Intel rdrnd instruction is available via 8512 -mrdrnd. 8513 * Two additional AVX vector conversion instructions are available via 8514 -mf16c. 8515 * Support for new Intel processor codename IvyBridge with RDRND, 8516 FSGSBASE and F16C is available through -march=core-avx-i. 8517 * Support for the new Intel processor codename Haswell with AVX2, 8518 FMA, BMI, BMI2, LZCNT is available through -march=core-avx2. 8519 * Support for new AMD family 15h processors (Piledriver core) is now 8520 available through -march=bdver2 and -mtune=bdver2 options. 8521 * Support for [39]the x32 psABI is now available through the -mx32 8522 option. 8523 * Windows mingw targets are using the -mms-bitfields option by 8524 default. 8525 * Windows x86 targets are using the __thiscall calling convention for 8526 C++ class-member functions. 8527 * Support for the configure option --with-threads=posix for Windows 8528 mingw targets. 8529 8530 MIPS 8531 8532 * GCC now supports thread-local storage (TLS) for MIPS16. This 8533 requires GNU binutils 2.22 or later. 8534 * GCC can now generate code specifically for the Cavium Octeon+ and 8535 Octeon2 processors. The associated command-line options are 8536 -march=octeon+ and -march=octeon2 respectively. Both options 8537 require GNU binutils 2.22 or later. 8538 * GCC can now work around certain 24k errata, under the control of 8539 the command-line option -mfix-24k. These workarounds require GNU 8540 binutils 2.20 or later. 8541 * 32-bit MIPS GNU/Linux targets such as mips-linux-gnu can now build 8542 n32 and n64 multilibs. The result is effectively a 64-bit GNU/Linux 8543 toolchain that generates 32-bit code by default. Use the 8544 configure-time option --enable-targets=all to select these extra 8545 multilibs. 8546 * Passing -fno-delayed-branch now also stops the assembler from 8547 automatically filling delay slots. 8548 8549 PowerPC/PowerPC64 8550 8551 * Vectors of type vector long long or vector long are passed and 8552 returned using the same method as other vectors with the VSX 8553 instruction set. Previously GCC did not adhere to the ABI for 8554 128-bit vectors with 64-bit integer base types (PR 48857). This 8555 will also be fixed in the GCC 4.6.1 and 4.5.4 releases. 8556 * A new option -mno-pointers-to-nested-functions was added to allow 8557 AIX 32-bit/64-bit and GNU/Linux 64-bit PowerPC users to specify 8558 that the compiler should not load up the chain register (r11) 8559 before calling a function through a pointer. If you use this 8560 option, you cannot call nested functions through a pointer, or call 8561 other languages that might use the static chain. 8562 * A new option msave-toc-indirect was added to allow AIX 8563 32-bit/64-bit and GNU/Linux 64-bit PowerPC users control whether we 8564 save the TOC in the prologue for indirect calls or generate the 8565 save inline. This can speed up some programs that call through a 8566 function pointer a lot, but it can slow down other functions that 8567 only call through a function pointer in exceptional cases. 8568 * The PowerPC port will now enable machine-specific built-in 8569 functions when the user switches the target machine using the 8570 #pragma GCC target or __attribute__ ((__target__ ("target"))) code 8571 sequences. In addition, the target macros are updated. However, due 8572 to the way the -save-temps switch is implemented, you won't see the 8573 effect of these additional macros being defined in preprocessor 8574 output. 8575 8576 SH 8577 8578 * A new option -msoft-atomic has been added. When it is specified, 8579 GCC will generate GNU/Linux-compatible gUSA atomic sequences for 8580 the new __atomic routines. 8581 * Since it is neither supported by GAS nor officially documented, 8582 code generation for little endian SH2A has been disabled. 8583 Specifying -ml with -m2a* will now result in a compiler error. 8584 * The defunct -mbranch-cost option has been fixed. 8585 * Some improvements to the generated code of: 8586 + Utilization of the tst #imm,R0 instruction. 8587 + Dynamic shift instructions on SH2A. 8588 + Integer absolute value calculations. 8589 * The -mdiv= option for targets other than SHmedia has been fixed and 8590 documented. 8591 8592 SPARC 8593 8594 * The option -mflat has been reinstated. When it is specified, the 8595 compiler will generate code for a single register window model. 8596 This is essentially a new implementation and the corresponding 8597 debugger support has been added to GDB 7.4. 8598 * Support for the options -mtune=native and -mcpu=native has been 8599 added on selected native platforms (GNU/Linux and Solaris). 8600 * Support for the SPARC T3 (Niagara 3) processor has been added. 8601 * VIS: 8602 + An intrinsics header visintrin.h has been added. 8603 + Builtin intrinsics for the VIS 1.0 edge handling and pixel 8604 compare instructions have been added. 8605 + The little-endian version of alignaddr is now supported. 8606 + When possible, VIS builtins are marked const, which should 8607 increase the compiler's ability to optimize VIS operations. 8608 + The compiler now properly tracks the %gsr register and how it 8609 behaves as an input for various VIS instructions. 8610 + Akin to fzero, the compiler can now generate fone instructions 8611 in order to set all of the bits of a floating-point register 8612 to 1. 8613 + The documentation for the VIS intrinsics in the GCC manual has 8614 been brought up to date and many inaccuracies were fixed. 8615 + Intrinsics for the VIS 2.0 bmask, bshuffle, and 8616 non-condition-code setting edge instructions have been added. 8617 Their availability is controlled by the new -mvis2 and 8618 -mno-vis2 options. They are enabled by default on 8619 UltraSPARC-III and later CPUs. 8620 * Support for UltraSPARC Fused Multiply-Add floating-point extensions 8621 has been added. These instructions are enabled by default on SPARC 8622 T3 (Niagara 3) and later CPUs. 8623 8624 TILE-Gx/TILEPro 8625 8626 * Support has been added for the Tilera TILE-Gx and TILEPro families 8627 of processors. 8628 8629 Other significant improvements 8630 8631 * A new option (-grecord-gcc-switches) was added that appends 8632 compiler command-line options that might affect code generation to 8633 the DW_AT_producer attribute string in the DWARF debugging 8634 information. 8635 * GCC now supports various new GNU extensions to the DWARF debugging 8636 information format, like [40]entry value and [41]call site 8637 information, [42]typed DWARF stack or [43]a more compact macro 8638 representation. Support for these extensions has been added to GDB 8639 7.4. They can be disabled through the -gstrict-dwarf command-line 8640 option. 8641 8642 GCC 4.7.1 8643 8644 This is the [44]list of problem reports (PRs) from GCC's bug tracking 8645 system that are known to be fixed in the 4.7.1 release. This list might 8646 not be complete (that is, it is possible that some PRs that have been 8647 fixed are not listed here). 8648 8649 The Go front end in the 4.7.1 release fully supports the [45]Go 1 8650 language standard. 8651 8652 GCC 4.7.2 8653 8654 This is the [46]list of problem reports (PRs) from GCC's bug tracking 8655 system that are known to be fixed in the 4.7.2 release. This list might 8656 not be complete (that is, it is possible that some PRs that have been 8657 fixed are not listed here). 8658 8659 GCC 4.7.3 8660 8661 This is the [47]list of problem reports (PRs) from GCC's bug tracking 8662 system that are known to be fixed in the 4.7.3 release. This list might 8663 not be complete (that is, it is possible that some PRs that have been 8664 fixed are not listed here). 8665 8666 GCC 4.7.4 8667 8668 This is the [48]list of problem reports (PRs) from GCC's bug tracking 8669 system that are known to be fixed in the 4.7.4 release. This list might 8670 not be complete (that is, it is possible that some PRs that have been 8671 fixed are not listed here). 8672 8673 8674 For questions related to the use of GCC, please consult these web 8675 pages and the [49]GCC manuals. If that fails, the 8676 [50]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 8677 web pages and the development of GCC are welcome on our developer 8678 list at [51]gcc (a] gcc.gnu.org. All of [52]our lists have public 8679 archives. 8680 8681 Copyright (C) [53]Free Software Foundation, Inc. Verbatim copying and 8682 distribution of this entire article is permitted in any medium, 8683 provided this notice is preserved. 8684 8685 These pages are [54]maintained by the GCC team. Last modified 8686 2023-03-29. 8687 8688 References 8689 8690 1. https://gcc.gnu.org/ml/gcc-patches/2011-03/msg01263.html 8691 2. http://savannah.nongnu.org/bugs/?35407 8692 3. https://gcc.gnu.org/PR18145 8693 4. https://gcc.gnu.org/gcc-4.7/porting_to.html 8694 5. https://gcc.gnu.org/wiki/TransactionalMemory 8695 6. https://gcc.gnu.org/wiki/Atomic/GCCMM 8696 7. http://gcc.gnu.org/gcc-4.7/cxx0x_status.html 8697 8. http://gcc.gnu.org/gcc-4.7/cxx0x_status.html 8698 9. http://gcc.gnu.org/gcc-4.7/cxx0x_status.html 8699 10. http://gcc.gnu.org/gcc-4.7/cxx0x_status.html 8700 11. http://gcc.gnu.org/gcc-4.7/cxx0x_status.html 8701 12. http://gcc.gnu.org/gcc-4.7/cxx0x_status.html 8702 13. https://gcc.gnu.org/PR14258 8703 14. https://gcc.gnu.org/PR35688 8704 15. https://gcc.gnu.org/onlinedocs/gcc-4.7.4/libstdc++/manual/manual/status.html#status.iso.2011 8705 16. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfstack-arrays_007d-254 8706 17. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/Optimize-Options.html#index-Ofast-689 8707 18. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfno-protect-parens_007d-270 8708 19. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfstack-arrays_007d-254 8709 20. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfrontend-optimize_007d-275 8710 21. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Error-and-Warning-Options.html#index-g_t_0040code_007bWfunction-elimination_007d-170 8711 22. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfaggressive-function-elimination_007d-270 8712 23. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Error-and-Warning-Options.html#index-g_t_0040code_007bWreal-q-constant_007d-149 8713 24. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/SELECTED_005fREAL_005fKIND.html 8714 25. https://learn.microsoft.com/en-us/windows/win32/wer/collecting-user-mode-dumps 8715 26. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Debugging-Options.html#index-g_t_0040code_007bfno-backtrace_007d-183 8716 27. https://gcc.gnu.org/wiki/Fortran2003Status 8717 28. https://gcc.gnu.org/wiki/OOP 8718 29. https://gcc.gnu.org/wiki/Fortran2008Status 8719 30. https://gcc.gnu.org/wiki/Coarray 8720 31. https://gcc.gnu.org/wiki/CoarrayLib 8721 32. https://gcc.gnu.org/wiki/TS29113Status 8722 33. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gfortran/Fortran-Dialect-Options.html#index-g_t_0040code_007bstd_003d_007d_0040var_007bstd_007d-option-53 8723 34. https://go.dev/doc/go1 8724 35. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/Named-Address-Spaces.html 8725 36. http://www.nongnu.org/avr-libc/ 8726 37. https://gcc.gnu.org/PR54461 8727 38. https://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/AVR-Built%5f002din-Functions.html 8728 39. https://sites.google.com/site/x32abi/ 8729 40. https://dwarfstd.org/issues/100909.1.html 8730 41. https://dwarfstd.org/issues/100909.2.html 8731 42. https://dwarfstd.org/issues/140425.1.html 8732 43. https://dwarfstd.org/issues/110722.1.html 8733 44. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.7.1 8734 45. https://go.dev/doc/go1 8735 46. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.7.2 8736 47. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.7.3 8737 48. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.7.4 8738 49. https://gcc.gnu.org/onlinedocs/ 8739 50. mailto:gcc-help (a] gcc.gnu.org 8740 51. mailto:gcc (a] gcc.gnu.org 8741 52. https://gcc.gnu.org/lists.html 8742 53. https://www.fsf.org/ 8743 54. https://gcc.gnu.org/about.html 8744 ====================================================================== 8745 http://gcc.gnu.org/gcc-4.6/index.html 8746 8747 GCC 4.6 Release Series 8748 8749 (This release series is no longer supported.) 8750 8751 April 12, 2013 8752 8753 The [1]GNU project and the GCC developers are pleased to announce the 8754 release of GCC 4.6.4. 8755 8756 This release is a bug-fix release, containing fixes for regressions in 8757 GCC 4.6.3 relative to previous releases of GCC. 8758 8759 Release History 8760 8761 GCC 4.6.4 8762 April 12, 2013 ([2]changes, [3]documentation) 8763 8764 GCC 4.6.3 8765 March 1, 2012 ([4]changes, [5]documentation) 8766 8767 GCC 4.6.2 8768 October 26, 2011 ([6]changes, [7]documentation) 8769 8770 GCC 4.6.1 8771 June 27, 2011 ([8]changes, [9]documentation) 8772 8773 GCC 4.6.0 8774 March 25, 2011 ([10]changes, [11]documentation) 8775 8776 References and Acknowledgements 8777 8778 GCC used to stand for the GNU C Compiler, but since the compiler 8779 supports several other languages aside from C, it now stands for the 8780 GNU Compiler Collection. 8781 8782 A list of [12]successful builds is updated as new information becomes 8783 available. 8784 8785 The GCC developers would like to thank the numerous people that have 8786 contributed new features, improvements, bug fixes, and other changes as 8787 well as test results to GCC. This [13]amazing group of volunteers is 8788 what makes GCC successful. 8789 8790 For additional information about GCC please refer to the [14]GCC 8791 project web site or contact the [15]GCC development mailing list. 8792 8793 To obtain GCC please use [16]our mirror sites or [17]our version 8794 control system. 8795 8796 8797 For questions related to the use of GCC, please consult these web 8798 pages and the [18]GCC manuals. If that fails, the 8799 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 8800 web pages and the development of GCC are welcome on our developer 8801 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 8802 archives. 8803 8804 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 8805 distribution of this entire article is permitted in any medium, 8806 provided this notice is preserved. 8807 8808 These pages are [23]maintained by the GCC team. Last modified 8809 2022-10-26. 8810 8811 References 8812 8813 1. http://www.gnu.org/ 8814 2. http://gcc.gnu.org/gcc-4.6/changes.html 8815 3. https://gcc.gnu.org/onlinedocs/4.6.4/ 8816 4. http://gcc.gnu.org/gcc-4.6/changes.html 8817 5. https://gcc.gnu.org/onlinedocs/4.6.3/ 8818 6. http://gcc.gnu.org/gcc-4.6/changes.html 8819 7. https://gcc.gnu.org/onlinedocs/4.6.2/ 8820 8. http://gcc.gnu.org/gcc-4.6/changes.html 8821 9. https://gcc.gnu.org/onlinedocs/4.6.1/ 8822 10. http://gcc.gnu.org/gcc-4.6/changes.html 8823 11. https://gcc.gnu.org/onlinedocs/4.6.0/ 8824 12. http://gcc.gnu.org/gcc-4.6/buildstat.html 8825 13. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 8826 14. http://gcc.gnu.org/index.html 8827 15. mailto:gcc (a] gcc.gnu.org 8828 16. http://gcc.gnu.org/mirrors.html 8829 17. http://gcc.gnu.org/git.html 8830 18. https://gcc.gnu.org/onlinedocs/ 8831 19. mailto:gcc-help (a] gcc.gnu.org 8832 20. mailto:gcc (a] gcc.gnu.org 8833 21. https://gcc.gnu.org/lists.html 8834 22. https://www.fsf.org/ 8835 23. https://gcc.gnu.org/about.html 8836 ====================================================================== 8837 http://gcc.gnu.org/gcc-4.6/changes.html 8838 8839 GCC 4.6 Release Series 8840 Changes, New Features, and Fixes 8841 8842 Caveats 8843 8844 * The options -b <machine> and -V <version> have been removed because 8845 they were unreliable. Instead, users should directly run 8846 <machine>-gcc when cross-compiling, or <machine>-gcc-<version> to 8847 run a different version of gcc. 8848 * GCC now has stricter checks for invalid command-line options. In 8849 particular, when gcc was called to link object files rather than 8850 compile source code, it would previously accept and ignore all 8851 options starting with --, including linker options such as 8852 --as-needed and --export-dynamic, although such options would 8853 result in errors if any source code was compiled. Such options, if 8854 unknown to the compiler, are now rejected in all cases; if the 8855 intent was to pass them to the linker, options such as 8856 -Wl,--as-needed should be used. 8857 * Versions of the GNU C library up to and including 2.11.1 included 8858 an [1]incorrect implementation of the cproj function. GCC optimizes 8859 its builtin cproj according to the behavior specified and allowed 8860 by the ISO C99 standard. If you want to avoid discrepancies between 8861 the C library and GCC's builtin transformations when using cproj in 8862 your code, use GLIBC 2.12 or later. If you are using an older GLIBC 8863 and actually rely on the incorrect behavior of cproj, then you can 8864 disable GCC's transformations using -fno-builtin-cproj. 8865 * The C-only intermodule optimization framework (IMA, enabled by 8866 -combine) has been removed in favor of the new generic link-time 8867 optimization framework (LTO) introduced in [2]GCC 4.5.0. 8868 * GCC now ships with the LGPL-licensed libquadmath library, which 8869 provides quad-precision mathematical functions for targets with a 8870 __float128 datatype. __float128 is available for targets on 32-bit 8871 x86, x86-64 and Itanium architectures. The libquadmath library is 8872 automatically built on such targets when building the Fortran 8873 compiler. 8874 * New -Wunused-but-set-variable and -Wunused-but-set-parameter 8875 warnings were added for C, C++, Objective-C and Objective-C++. 8876 These warnings diagnose variables respective parameters which are 8877 only set in the code and never otherwise used. Usually such 8878 variables are useless and often even the value assigned to them is 8879 computed needlessly, sometimes expensively. The 8880 -Wunused-but-set-variable warning is enabled by default by -Wall 8881 flag and -Wunused-but-set-parameter by -Wall -Wextra flags. 8882 * On ARM, a bug has been fixed in GCC's implementation of the AAPCS 8883 rules for the layout of vectors that could lead to wrong code being 8884 generated. Vectors larger than 8 bytes in size are now by default 8885 aligned to an 8-byte boundary. This is an ABI change: code that 8886 makes explicit use of vector types may be incompatible with binary 8887 objects built with older versions of GCC. Auto-vectorized code is 8888 not affected by this change. (This change affects GCC versions 8889 4.6.4 and later, with the exception of versions 4.7.0 and 4.7.1.) 8890 * On AVR, variables with the progmem attribute to locate data in 8891 flash memory must be qualified as const. 8892 * Support for a number of older systems and recently unmaintained or 8893 untested target ports of GCC has been declared obsolete in GCC 4.6. 8894 Unless there is activity to revive them, the next release of GCC 8895 will have their sources permanently removed. 8896 All GCC ports for the following processor architectures have been 8897 declared obsolete: 8898 + Argonaut ARC (arc-*) 8899 + National Semiconductor CRX (crx-*) 8900 + Motorola 68HC11 and 68HC12 (m68hc11-*-*, m6811-*-*, 8901 m68hc12-*-*, m6812-*-*) 8902 + Sunplus S+core (score-*) 8903 The following ports for individual systems on particular 8904 architectures have been obsoleted: 8905 + Interix (i[34567]86-*-interix3*) 8906 + NetWare x86 (i[3456x]86-*-netware*) 8907 + Generic ARM PE (arm-*-pe* other than arm*-wince-pe*) 8908 + MCore PE (mcore-*-pe*) 8909 + SH SymbianOS (sh*-*-symbianelf*) 8910 + GNU Hurd on Alpha and PowerPC (alpha*-*-gnu*, powerpc*-*-gnu*) 8911 + M68K uClinux old ABI (m68k-*-uclinuxoldabi*) 8912 + a.out NetBSD (arm*-*-netbsd*, i[34567]86-*-netbsd*, 8913 vax-*-netbsd*, but not *-*-netbsdelf*) 8914 The i[34567]86-*-pe alias for Cygwin targets has also been 8915 obsoleted; users should configure for i[34567]86-*-cygwin* instead. 8916 Certain configure options to control the set of libraries built 8917 with GCC on some targets have been obsoleted. On ARM targets, the 8918 options --disable-fpu, --disable-26bit, --disable-underscore, 8919 --disable-interwork, --disable-biendian and --disable-nofmult have 8920 been obsoleted. On MIPS targets, the options 8921 --disable-single-float, --disable-biendian and --disable-softfloat 8922 have been obsoleted. 8923 * Support has been removed for all the [3]configurations obsoleted in 8924 GCC 4.5. 8925 * More information on porting to GCC 4.6 from previous versions of 8926 GCC can be found in the [4]porting guide for this release. 8927 8928 General Optimizer Improvements 8929 8930 * A new general optimization level, -Ofast, has been introduced. It 8931 combines the existing optimization level -O3 with options that can 8932 affect standards compliance but result in better optimized code. 8933 For example, -Ofast enables -ffast-math. 8934 * Link-time optimization improvements: 8935 + The [5]Scalable Whole Program Optimizer (WHOPR) project has 8936 stabilized to the point of being usable. It has become the 8937 default mode when using the LTO optimization model. Link time 8938 optimization can now split itself into multiple parallel 8939 compilations. Parallelism is controlled with -flto=n (where n 8940 specifies the number of compilations to execute in parallel). 8941 GCC can also cooperate with a GNU make job server by 8942 specifying the -flto=jobserver option and adding + to the 8943 beginning of the Makefile rule executing the linker. 8944 Classical LTO mode can be enforced by -flto-partition=none. 8945 This may result in small code quality improvements. 8946 + A large number of bugs were fixed. GCC itself, Mozilla Firefox 8947 and other large applications can be built with LTO enabled. 8948 + The linker plugin support improvements 8949 o Linker plugin is now enabled by default when the linker 8950 is detected to have plugin support. This is the case for 8951 GNU ld 2.21.51 or newer (on ELF and Cygwin targets) and 8952 the Gold linker on ELF targets. Plugin support of the 8953 Apple linker on Darwin is not compatible with GCC. The 8954 linker plugin can also be controlled by the 8955 -fuse-linker-plugin command-line option. 8956 o Resolution information from the linker plugin is used to 8957 drive whole program assumptions. Use of the linker plugin 8958 results in more aggressive optimization on binaries and 8959 on shared libraries that use the hidden visibility 8960 attribute. Consequently the use of -fwhole-program is not 8961 necessary in addition to LTO. 8962 + Hidden symbols used from non-LTO objects now have to be 8963 explicitly annotated with externally_visible when the linker 8964 plugin is not used. 8965 + C++ inline functions and virtual tables are now privatized 8966 more aggressively, leading to better inter-procedural 8967 optimization and faster dynamic linking. 8968 + Memory usage and intermediate language streaming performance 8969 have been improved. 8970 + Static constructors and destructors from individual units are 8971 inlined into a single function. This can significantly improve 8972 startup times of large C++ applications where static 8973 constructors are very common. For example, static constructors 8974 are used when including the iostream header. 8975 + Support for the Ada language has been added. 8976 * Interprocedural optimization improvements 8977 + The interprocedural framework was re-tuned for link time 8978 optimization. Several scalability issues were resolved. 8979 + Improved auto-detection of const and pure functions. Newly, 8980 noreturn functions are auto-detected. 8981 The [6]-Wsuggest-attribute=[const|pure|noreturn] flag is 8982 available that informs users when adding attributes to headers 8983 might improve code generation. 8984 + A number of inlining heuristic improvements. In particular: 8985 o Partial inlining is now supported and enabled by default 8986 at -O2 and greater. The feature can be controlled via 8987 -fpartial-inlining. 8988 Partial inlining splits functions with short hot path to 8989 return. This allows more aggressive inlining of the hot 8990 path leading to better performance and often to code size 8991 reductions (because cold parts of functions are not 8992 duplicated). 8993 o Scalability for large compilation units was improved 8994 significantly. 8995 o Inlining of callbacks is now more aggressive. 8996 o Virtual methods are considered for inlining when the 8997 caller is inlined and devirtualization is then possible. 8998 o Inlining when optimizing for size (either in cold regions 8999 of a program or when compiling with -Os) was improved to 9000 better handle C++ programs with larger abstraction 9001 penalty, leading to smaller and faster code. 9002 + The IPA reference optimization pass detecting global variables 9003 used or modified by functions was strengthened and sped up. 9004 + Functions whose address was taken are now optimized out when 9005 all references to them are dead. 9006 + A new inter-procedural static profile estimation pass detects 9007 functions that are executed once or unlikely to be executed. 9008 Unlikely executed functions are optimized for size. Functions 9009 executed once are optimized for size except for the inner 9010 loops. 9011 + On most targets with named section support, functions used 9012 only at startup (static constructors and main), functions used 9013 only at exit and functions detected to be cold are placed into 9014 separate text segment subsections. This extends the 9015 -freorder-functions feature and is controlled by the same 9016 switch. The goal is to improve the startup time of large C++ 9017 programs. 9018 Proper function placement requires linker support. GNU ld 9019 2.21.51 on ELF targets was updated to place those functions 9020 together within the text section leading to better code 9021 locality and faster startup times of large C++ programs. The 9022 feature is also supported in the Apple linker. Support in the 9023 gold linker is planned. 9024 * A new switch -fstack-usage has been added. It makes the compiler 9025 output stack usage information for the program, on a per-function 9026 basis, in an auxiliary file. 9027 * A new switch -fcombine-stack-adjustments has been added. It can be 9028 used to enable or disable the compiler's stack-slot combining pass 9029 which before was enabled automatically at -O1 and above, but could 9030 not be controlled on its own. 9031 * A new switch -fstrict-volatile-bitfields has been added. Using it 9032 indicates that accesses to volatile bitfields should use a single 9033 access of the width of the field's type. This option can be useful 9034 for precisely defining and accessing memory-mapped peripheral 9035 registers from C or C++. 9036 9037 Compile time and memory usage improvements 9038 9039 * Datastructures used by the dataflow framework in GCC were 9040 reorganized for better memory usage and more cache locality. 9041 Compile time is improved especially on units with large functions 9042 (possibly resulting from a lot of inlining) not fitting into the 9043 processor cache. The compile time of the GCC C compiler binary with 9044 link-time optimization went down by over 10% (benchmarked on x86-64 9045 target). 9046 9047 New Languages and Language specific improvements 9048 9049 Ada 9050 9051 * Stack checking has been improved on selected architectures (Alpha, 9052 IA-32/x86-64, RS/6000 and SPARC): it now will detect stack 9053 overflows in all cases on these architectures. 9054 * Initial support for Ada 2012 has been added. 9055 9056 C family 9057 9058 * A new warning, enabled by -Wdouble-promotion, has been added that 9059 warns about cases where a value of type float is implicitly 9060 promoted to double. This is especially helpful for CPUs that handle 9061 the former in hardware, but emulate the latter in software. 9062 * A new function attribute leaf was introduced. This attribute allows 9063 better inter-procedural optimization across calls to functions that 9064 return to the current unit only via returning or exception 9065 handling. This is the case for most library functions that have no 9066 callbacks. 9067 * Support for a new data type __int128 for targets having wide enough 9068 machine-mode support. 9069 * The new function attribute callee_pop_aggregate allows to specify 9070 if the caller or callee is responsible for popping the aggregate 9071 return pointer value from the stack. 9072 * Support for selectively enabling and disabling warnings via #pragma 9073 GCC diagnostic has been added. For instance: 9074 #pragma GCC diagnostic error "-Wuninitialized" 9075 foo(a); /* error is given for this one */ 9076 #pragma GCC diagnostic push 9077 #pragma GCC diagnostic ignored "-Wuninitialized" 9078 foo(b); /* no diagnostic for this one */ 9079 #pragma GCC diagnostic pop 9080 foo(c); /* error is given for this one */ 9081 #pragma GCC diagnostic pop 9082 foo(d); /* depends on command-line options */ 9083 9084 * The -fmax-errors=N option is now supported. Using this option 9085 causes the compiler to exit after N errors have been issued. 9086 9087 C 9088 9089 * There is now experimental support for some features from the 9090 upcoming C1X revision of the ISO C standard. This support may be 9091 selected with -std=c1x, or -std=gnu1x for C1X with GNU extensions. 9092 Note that this support is experimental and may change incompatibly 9093 in future releases for consistency with changes to the C1X standard 9094 draft. The following features are newly supported as described in 9095 the N1539 draft of C1X (with changes agreed at the March 2011 WG14 9096 meeting); some other features were already supported with no 9097 compiler changes being needed, or have some support but not in full 9098 accord with N1539 (as amended). 9099 + Static assertions (_Static_assert keyword) 9100 + Typedef redefinition 9101 + New macros in <float.h> 9102 + Anonymous structures and unions 9103 * The new -fplan9-extensions option directs the compiler to support 9104 some extensions for anonymous struct fields which are implemented 9105 by the Plan 9 compiler. A pointer to a struct may be automatically 9106 converted to a pointer to an anonymous field when calling a 9107 function, in order to make the types match. An anonymous struct 9108 field whose type is a typedef name may be referred to using the 9109 typedef name. 9110 9111 C++ 9112 9113 * Improved [7]experimental support for the upcoming C++0x ISO C++ 9114 standard, including support for constexpr (thanks to Gabriel Dos 9115 Reis and Jason Merrill), nullptr (thanks to Magnus Fromreide), 9116 noexcept, unrestricted unions, range-based for loops (thanks to 9117 Rodrigo Rivas Costa), opaque enum declarations (thanks also to 9118 Rodrigo), implicitly deleted functions and implicit move 9119 constructors. 9120 * When an extern declaration within a function does not match a 9121 declaration in the enclosing context, G++ now properly declares the 9122 name within the namespace of the function rather than the namespace 9123 which was open just before the function definition ([8]c++/43145). 9124 * GCC now warns by default when casting integers to larger pointer 9125 types. These warnings can be disabled with the option 9126 -Wno-int-to-pointer-cast, which is now also available in C++. 9127 * G++ no longer optimizes using the assumption that a value of 9128 enumeration type will fall within the range specified by the 9129 standard, since that assumption is easily violated with a 9130 conversion from integer type ([9]c++/43680). The old behavior can 9131 be restored with -fstrict-enums. 9132 * The new -fnothrow-opt flag changes the semantics of a throw() 9133 exception specification to match the proposed semantics of the 9134 noexcept specification: just call terminate if an exception tries 9135 to propagate out of a function with such an exception 9136 specification. This dramatically reduces or eliminates the code 9137 size overhead from adding the exception specification. 9138 * The new -Wnoexcept flag will suggest adding a noexcept qualifier to 9139 a function that the compiler can tell doesn't throw if it would 9140 change the value of a noexcept expression. 9141 * The -Wshadow option now warns if a local variable or type 9142 declaration shadows another type in C++. Note that the compiler 9143 will not warn if a local variable shadows a struct/class/enum, but 9144 will warn if it shadows an explicit typedef. 9145 * When an identifier is not found in the current scope, G++ now 9146 offers suggestions about which identifier might have been intended. 9147 * G++ now issues clearer diagnostics for missing semicolons after 9148 class, struct, and union definitions. 9149 * G++ now issues clearer diagnostics for missing semicolons after 9150 class member declarations. 9151 * G++ now issues clearer diagnostics when a colon is used in a place 9152 where a double-colon was intended. 9153 * G++ no longer accepts mutable on reference members ([10]c++/33558). 9154 Use -fpermissive to allow the old, non-conforming behaviour. 9155 * A few mangling fixes have been made, to attribute const/volatile on 9156 function pointer types, decltype of a plain decl, and use of a 9157 function parameter in the declaration of another parameter. By 9158 default the compiler still uses the old mangling, but emits aliases 9159 with the new mangling on targets that support strong aliases. Users 9160 can switch over entirely to the new mangling with -fabi-version=5 9161 or -fabi-version=0. -Wabi will now warn about code that uses the 9162 old mangling. 9163 * In 4.6.0 and 4.6.1 G++ no longer allows objects of const-qualified 9164 type to be default initialized unless the type has a user-declared 9165 default constructor. In 4.6.2 G++ implements the proposed 9166 resolution of [11]DR 253, so default initialization is allowed if 9167 it initializes all subobjects. Code that fails to compile can be 9168 fixed by providing an initializer e.g. 9169 struct A { A(); }; 9170 struct B : A { int i; }; 9171 const B b = B(); 9172 Use -fpermissive to allow the old, non-conforming behaviour. 9173 9174 Runtime Library (libstdc++) 9175 9176 * [12]Improved experimental support for the upcoming ISO C++ 9177 standard, C++0x, including using constexpr and nullptr. 9178 * Performance improvements to the [13]Debug Mode, thanks to Franois 9179 Dumont. 9180 * Atomic operations used for reference-counting are annotated so that 9181 they can be understood by race detectors such as Helgrind, see 9182 [14]Data Race Hunting. 9183 * Most libstdc++ standard headers have been changed to no longer 9184 include the cstddef header as an implementation detail. Code that 9185 relied on that header being included as side-effect of including 9186 other standard headers will need to include cstddef explicitly. 9187 9188 Fortran 9189 9190 * On systems supporting the libquadmath library, GNU Fortran now also 9191 supports a quad-precision, kind=16 floating-point data type 9192 (REAL(16), COMPLEX(16)). As the data type is not fully supported in 9193 hardware, calculations might be one to two orders of magnitude 9194 slower than with the 4, 8 or 10 bytes floating-point data types. 9195 This change does not affect systems which support REAL(16) in 9196 hardware nor those which do not support libquadmath. 9197 * Much improved compile time for large array constructors. 9198 * In order to reduce execution time and memory consumption, use of 9199 temporary arrays in assignment expressions is avoided for many 9200 cases. The compiler now reverses loops in order to avoid generating 9201 a temporary array where possible. 9202 * Improved diagnostics, especially with -fwhole-file. 9203 * The -fwhole-file flag is now enabled by default. This improves code 9204 generation and diagnostics. It can be disabled using the deprecated 9205 -fno-whole-file flag. 9206 * Support the generation of Makefile dependencies via the [15]-M... 9207 flags of GCC; you may need to specify the -cpp option in addition. 9208 The dependencies take modules, Fortran's include, and CPP's 9209 #include into account. Note: Using -M for the module path is no 9210 longer supported, use -J instead. 9211 * The flag -Wconversion has been modified to only issue warnings 9212 where a conversion leads to information loss. This drastically 9213 reduces the number of warnings; -Wconversion is thus now enabled 9214 with -Wall. The flag -Wconversion-extra has been added and also 9215 warns about other conversions; -Wconversion-extra typically issues 9216 a huge number of warnings, most of which can be ignored. 9217 * A new command-line option -Wunused-dummy-argument warns about 9218 unused dummy arguments and is included in -Wall. Before, 9219 -Wunused-variable also warned about unused dummy arguments. 9220 * Fortran 2003 support has been extended: 9221 + Improved support for polymorphism between libraries and 9222 programs and for complicated inheritance patterns (cf. 9223 [16]object-oriented programming). 9224 + Experimental support of the ASSOCIATE construct. 9225 + In pointer assignments it is now possible to specify the lower 9226 bounds of the pointer and, for a rank-1 or a simply contiguous 9227 data-target, to remap the bounds. 9228 + Automatic (re)allocation: In intrinsic assignments to 9229 allocatable variables the left-hand side will be automatically 9230 allocated (if unallocated) or reallocated (if the shape or 9231 type parameter is different). To avoid the small performance 9232 penalty, you can use a(:) = ... instead of a = ... for arrays 9233 and character strings - or disable the feature using -std=f95 9234 or -fno-realloc-lhs. 9235 + Deferred type parameter: For scalar allocatable and pointer 9236 variables the character length can be deferred. 9237 + Namelist variables with allocatable and pointer attribute and 9238 nonconstant length type parameter are supported. 9239 * Fortran 2008 support has been extended: 9240 + Experimental [17]coarray support (for one image only, i.e. 9241 num_images() == 1); use the [18]-fcoarray=single flag to 9242 enable it. 9243 + The STOP and the new ERROR STOP statements now support all 9244 constant expressions. 9245 + Support for the CONTIGUOUS attribute. 9246 + Support for ALLOCATE with MOLD. 9247 + Support for the STORAGE_SIZE intrinsic inquiry function. 9248 + Support of the NORM2 and PARITY intrinsic functions. 9249 + The following bit intrinsics were added: POPCNT and POPPAR for 9250 counting the number of 1 bits and returning the parity; BGE, 9251 BGT, BLE, and BLT for bitwise comparisons; DSHIFTL and DSHIFTR 9252 for combined left and right shifts, MASKL and MASKR for simple 9253 left and right justified masks, MERGE_BITS for a bitwise merge 9254 using a mask, SHIFTA, SHIFTL and SHIFTR for shift operations, 9255 and the transformational bit intrinsics IALL, IANY and 9256 IPARITY. 9257 + Support of the EXECUTE_COMMAND_LINE intrinsic subroutine. 9258 + Support for the IMPURE attribute for procedures, which allows 9259 for ELEMENTAL procedures without the restrictions of PURE. 9260 + Null pointers (including NULL()) and not allocated variables 9261 can be used as actual argument to optional non-pointer, 9262 non-allocatable dummy arguments, denoting an absent argument. 9263 + Non-pointer variables with TARGET attribute can be used as 9264 actual argument to POINTER dummies with INTENT(IN) 9265 + Pointers including procedure pointers and those in a derived 9266 type (pointer components) can now be initialized by a target 9267 instead of only by NULL. 9268 + The EXIT statement (with construct-name) can now be used to 9269 leave not only the DO but also the ASSOCIATE, BLOCK, IF, 9270 SELECT CASE and SELECT TYPE constructs. 9271 + Internal procedures can now be used as actual argument. 9272 + The named constants INTEGER_KINDS, LOGICAL_KINDS, REAL_KINDS 9273 and CHARACTER_KINDS of the intrinsic module ISO_FORTRAN_ENV 9274 have been added; these arrays contain the supported kind 9275 values for the respective types. 9276 + The module procedures C_SIZEOF of the intrinsic module 9277 ISO_C_BINDINGS and COMPILER_VERSION and COMPILER_OPTIONS of 9278 ISO_FORTRAN_ENV have been implemented. 9279 + Minor changes: obsolescence diagnostics for ENTRY was added 9280 for -std=f2008; a line may start with a semicolon; for 9281 internal and module procedures END can be used instead of END 9282 SUBROUTINE and END FUNCTION; SELECTED_REAL_KIND now also takes 9283 a RADIX argument; intrinsic types are supported for 9284 TYPE(intrinsic-type-spec); multiple type-bound procedures can 9285 be declared in a single PROCEDURE statement; implied-shape 9286 arrays are supported for named constants (PARAMETER). The 9287 transformational, three argument versions of BESSEL_JN and 9288 BESSEL_YN were added - the elemental, two-argument version had 9289 been added in GCC 4.4; note that the transformational 9290 functions use a recurrence algorithm. 9291 9292 Go 9293 9294 Support for the Go programming language has been added to GCC. It is 9295 not enabled by default when you build GCC; use the --enable-languages 9296 configure option to build it. The driver program for compiling Go code 9297 is gccgo. 9298 9299 Go is currently known to work on GNU/Linux and RTEMS. Solaris support 9300 is in progress. It may or may not work on other platforms. 9301 9302 Objective-C and Objective-C++ 9303 9304 * The -fobjc-exceptions flag is now required to enable Objective-C 9305 exception and synchronization syntax (introduced by the keywords 9306 @try, @catch, @finally and @synchronized). 9307 * A number of Objective-C 2.0 features and extensions are now 9308 supported by GCC. These features are enabled by default; you can 9309 disable them by using the new -fobjc-std=objc1 command-line option. 9310 * The Objective-C 2.0 dot-syntax is now supported. It is an 9311 alternative syntax for using getters and setters; object.count is 9312 automatically converted into [object count] or [object setCount: 9313 ...] depending on context; for example if (object.count > 0) is 9314 automatically compiled into the equivalent of if ([object count] > 9315 0) while object.count = 0; is automatically compiled into the 9316 equivalent ot [object setCount: 0];. The dot-syntax can be used 9317 with instance and class objects and with any setters or getters, no 9318 matter if they are part of a declared property or not. 9319 * Objective-C 2.0 declared properties are now supported. They are 9320 declared using the new @property keyword, and are most commonly 9321 used in conjunction with the new Objective-C 2.0 dot-syntax. The 9322 nonatomic, readonly, readwrite, assign, retain, copy, setter and 9323 getter attributes are all supported. Marking declared properties 9324 with __attribute__ ((deprecated)) is supported too. 9325 * The Objective-C 2.0 @synthesize and @dynamic keywords are 9326 supported. @synthesize causes the compiler to automatically 9327 synthesize a declared property, while @dynamic is used to disable 9328 all warnings for a declared property for which no implementation is 9329 provided at compile time. Synthesizing declared properties requires 9330 runtime support in most useful cases; to be able to use it with the 9331 GNU runtime, appropriate helper functions have been added to the 9332 GNU Objective-C runtime ABI, and are implemented by the GNU 9333 Objective-C runtime library shipped with GCC. 9334 * The Objective-C 2.0 fast enumeration syntax is supported in 9335 Objective-C. This is currently not yet available in Objective-C++. 9336 Fast enumeration requires support in the runtime, and such support 9337 has been added to the GNU Objective-C runtime library (shipped with 9338 GCC). 9339 * The Objective-C 2.0 @optional keyword is supported. It allows you 9340 to mark methods or properties in a protocol as optional as opposed 9341 to required. 9342 * The Objective-C 2.0 @package keyword is supported. It has currently 9343 the same effect as the @public keyword. 9344 * Objective-C 2.0 method attributes are supported. Currently the 9345 supported attributes are deprecated, sentinel, noreturn and format. 9346 * Objective-C 2.0 method argument attributes are supported. The most 9347 widely used attribute is unused, to mark an argument as unused in 9348 the implementation. 9349 * Objective-C 2.0 class and protocol attributes are supported. 9350 Currently the only supported attribute is deprecated. 9351 * Objective-C 2.0 class extensions are supported. A class extension 9352 has the same syntax as a category declaration with no category 9353 name, and the methods and properties declared in it are added 9354 directly to the main class. It is mostly used as an alternative to 9355 a category to add methods to a class without advertising them in 9356 the public headers, with the advantage that for class extensions 9357 the compiler checks that all the privately declared methods are 9358 actually implemented. 9359 * As a result of these enhancements, GCC can now be used to build 9360 Objective-C and Objective-C++ software that uses Foundation and 9361 other important system frameworks with the NeXT runtime on Darwin 9 9362 and Darwin 10 (OSX 10.5 and 10.6). 9363 * Many bugs in the compiler have been fixed in this release; in 9364 particular, LTO can now be used when compiling Objective-C and 9365 Objective-C++ and the parser is much more robust in dealing with 9366 invalid code. 9367 9368 Runtime Library (libobjc) 9369 9370 * The GNU Objective-C runtime library now defines the macro 9371 __GNU_LIBOBJC__ (with a value that is increased at every release 9372 where there is any change to the API) in objc/objc.h, making it 9373 easy to determine if the GNU Objective-C runtime library is being 9374 used, and if so, which version. Previous versions of the GNU 9375 Objective-C runtime library (and other Objective-C runtime 9376 libraries such as the Apple one) do not define this macro. 9377 * A new Objective-C 2.0 API, almost identical to the one implemented 9378 by the Apple Objective-C runtime, has been implemented in the GNU 9379 Objective-C runtime library. The new API hides the internals of 9380 most runtime structures but provides a more extensive set of 9381 functions to operate on them. It is much easier, for example, to 9382 create or modify classes at runtime. The new API also makes it 9383 easier to port software from Apple to GNU as almost no changes 9384 should be required. The old API is still supported for backwards 9385 compatibility; including the old objc/objc-api.h header file 9386 automatically selects the old API, while including the new 9387 objc/runtime.h header file automatically selects the new API. 9388 Support for the old API is being phased out and upgrading the 9389 software to use the new API is strongly recommended. To check for 9390 the availability of the new API, the __GNU_LIBOBJC__ macro can be 9391 used as older versions of the GNU Objective-C runtime library, 9392 which do not support the new API, do not define such a macro. 9393 * Runtime support for @synchronized has been added. 9394 * Runtime support for Objective-C 2.0 synthesized property accessors 9395 has been added. 9396 * Runtime support for Objective-C 2.0 fast enumeration has been 9397 added. 9398 9399 New Targets and Target Specific Improvements 9400 9401 ARM 9402 9403 * GCC now supports the Cortex-M4 processor implementing the v7-em 9404 version of the architecture using the option -mcpu=cortex-m4. 9405 * Scheduling descriptions for the Cortex-M4, the Neon and the 9406 floating point units of the Cortex-A9 and a pipeline description 9407 for the Cortex-A5 have been added. 9408 * Synchronization primitives such as __sync_fetch_and_add and friends 9409 are now inlined for supported architectures rather than calling 9410 into a kernel helper function. 9411 * SSA loop prefetching is enabled by default for the Cortex-A9 at 9412 -O3. 9413 * Several improvements were committed to improve code generation for 9414 the ARM architecture including a rewritten implementation for load 9415 and store multiples. 9416 * Several enhancements were committed to improve SIMD code generation 9417 for NEON by adding support for widening instructions, misaligned 9418 loads and stores, vector conditionals and support for 64 bit 9419 arithmetic. 9420 * Support was added for the Faraday cores fa526, fa606te, fa626te, 9421 fmp626te, fmp626 and fa726te and can be used with the respective 9422 names as parameters to the -mcpu= option. 9423 * Basic support was added for Cortex-A15 and is available through 9424 -mcpu=cortex-a15. 9425 * GCC for AAPCS configurations now more closely adheres to the AAPCS 9426 specification by enabling -fstrict-volatile-bitfields by default. 9427 9428 IA-32/x86-64 9429 9430 * The new -fsplit-stack option permits programs to use a 9431 discontiguous stack. This is useful for threaded programs, in that 9432 it is no longer necessary to specify the maximum stack size when 9433 creating a thread. This feature is currently only implemented for 9434 32-bit and 64-bit x86 GNU/Linux targets. 9435 * Support for emitting profiler counter calls before function 9436 prologues. This is enabled via a new command-line option -mfentry. 9437 * Optimization for the Intel Core 2 processors is now available 9438 through the -march=core2 and -mtune=core2 options. 9439 * Support for Intel Core i3/i5/i7 processors is now available through 9440 the -march=corei7 and -mtune=corei7 options. 9441 * Support for Intel Core i3/i5/i7 processors with AVX is now 9442 available through the -march=corei7-avx and -mtune=corei7-avx 9443 options. 9444 * Support for AMD Bobcat (family 14) processors is now available 9445 through the -march=btver1 and -mtune=btver1 options. 9446 * Support for AMD Bulldozer (family 15) processors is now available 9447 through the -march=bdver1 and -mtune=bdver1 options. 9448 * The default setting (when not optimizing for size) for 32-bit 9449 GNU/Linux and Darwin x86 targets has been changed to 9450 -fomit-frame-pointer. The default can be reverted to 9451 -fno-omit-frame-pointer by configuring GCC with the 9452 --enable-frame-pointer configure option. 9453 * Darwin, FreeBSD, Solaris 2, MinGW and Cygwin now all support 9454 __float128 on 32-bit and 64-bit x86 targets. 9455 * AVX floating-point arithmetic can now be enabled by default at 9456 configure time with the new --with-fpmath=avx option. 9457 * The SSA loop prefetching pass is enabled when using -O3 when 9458 optimizing for CPUs where prefetching is beneficial (AMD CPUs newer 9459 than K6). 9460 * Support for TBM (Trailing Bit Manipulation) built-in functions and 9461 code generation is available via -mtbm. 9462 * Support for AMD's BMI (Bit Manipulation) built-in functions and 9463 code generation is available via -mbmi. 9464 9465 MicroBlaze 9466 9467 * Support has been added for the Xilinx MicroBlaze softcore processor 9468 (microblaze-elf) embedded target. This configurable processor is 9469 supported on several Xilinx Spartan and Virtex FPGAs. 9470 9471 MIPS 9472 9473 * GCC now supports the Loongson 3A processor. Its canonical -march= 9474 and -mtune= name is loongson3a. 9475 9476 MN10300 / AM33 9477 9478 * The inline assembly register constraint "A" has been renamed "c". 9479 This constraint is used to select a floating-point register that 9480 can be used as the destination of a multiply-accumulate 9481 instruction. 9482 * New inline assembly register constraints "A" and "D" have been 9483 added. These constraint letters resolve to all general registers 9484 when compiling for AM33, and resolve to address registers only or 9485 data registers only when compiling for MN10300. 9486 * The MDR register is represented in the compiler. One can access the 9487 register via the "z" constraint in inline assembly. It can be 9488 marked as clobbered or used as a local register variable via the 9489 "mdr" name. The compiler uses the RETF instruction if the function 9490 does not modify the MDR register, so it is important that inline 9491 assembly properly annotate any usage of the register. 9492 9493 PowerPC/PowerPC64 9494 9495 * GCC now supports the Applied Micro Titan processor with 9496 -mcpu=titan. 9497 * The -mrecip option has been added, which indicates whether the 9498 reciprocal and reciprocal square root instructions should be used. 9499 * The -mveclibabi=mass option can be used to enable the compiler to 9500 autovectorize mathematical functions using the Mathematical 9501 Acceleration Subsystem library. 9502 * The -msingle-pic-base option has been added, which instructs the 9503 compiler to avoid loading the PIC base register in function 9504 prologues. The PIC base register must be initialized by the runtime 9505 system. 9506 * The -mblock-move-inline-limit option has been added, which enables 9507 the user to control the maximum size of inlined memcpy calls and 9508 similar. 9509 * PowerPC64 GNU/Linux support for applications requiring a large TOC 9510 section has been improved. A new command-line option, 9511 -mcmodel=MODEL, controls this feature; valid values for MODEL are 9512 small, medium, or large. 9513 * The Altivec builtin functions vec_ld and vec_st have been modified 9514 to generate the Altivec memory instructions LVX and STVX, even if 9515 the -mvsx option is used. In the initial GCC 4.5 release, these 9516 builtin functions were changed to generate VSX memory reference 9517 instructions instead of Altivec memory instructions, but there are 9518 differences between the two instructions. If the VSX instruction 9519 set is available, you can now use the new builtin functions 9520 vec_vsx_ld and vec_vsx_st which always generates the VSX memory 9521 instructions. 9522 * The GCC compiler on AIX now defaults to a process layout with a 9523 larger data space allowing larger programs to be compiled. 9524 * The GCC long double type on AIX 6.1 and above has reverted to 64 9525 bit double precision, matching the AIX XL compiler default, because 9526 of missing C99 symbols required by the GCC runtime. 9527 * The default processor scheduling model and tuning for PowerPC64 9528 GNU/Linux and for AIX 6.1 and above now is POWER7. 9529 * Starting with GCC 4.6.1, vectors of type vector long long or vector 9530 long are passed and returned in the same method as other vectors 9531 with the VSX instruction set. Previously the GCC compiler did not 9532 adhere to the ABI for 128-bit vectors with 64-bit integer base 9533 types (PR 48857). This is also fixed in the GCC 4.5.4 release. 9534 9535 S/390, zSeries and System z9/z10, IBM zEnterprise z196 9536 9537 * Support for the zEnterprise z196 processor has been added. When 9538 using the -march=z196 option, the compiler will generate code 9539 making use of the following instruction facilities: 9540 + Conditional load/store 9541 + Distinct-operands 9542 + Floating-point-extension 9543 + Interlocked-access 9544 + Population-count 9545 The -mtune=z196 option avoids the compare and branch instructions 9546 as well as the load address instruction with an index register as 9547 much as possible and performs instruction scheduling appropriate 9548 for the new out-of-order pipeline architecture. 9549 * When using the -m31 -mzarch options the generated code still 9550 conforms to the 32-bit ABI but uses the general purpose registers 9551 as 64-bit registers internally. This requires a Linux kernel saving 9552 the whole 64-bit registers when doing a context switch. Kernels 9553 providing that feature indicate that by the 'highgprs' string in 9554 /proc/cpuinfo. 9555 * The SSA loop prefetching pass is enabled when using -O3. 9556 9557 SPARC 9558 9559 * GCC now supports the LEON series of SPARC V8 processors. The code 9560 generated by the compiler can either be tuned to it by means of the 9561 --with-tune=leon configure option and -mtune=leon compilation 9562 option, or the compiler can be built for the sparc-leon-{elf,linux} 9563 and sparc-leon3-{elf,linux} targets directly. 9564 * GCC has stopped sign/zero-extending parameter registers in the 9565 callee for functions taking parameters with sub-word size in 32-bit 9566 mode, since this is redundant with the specification of the ABI. 9567 GCC has never done so in 64-bit mode since this is also redundant. 9568 * The command-line option -mfix-at697f has been added to enable the 9569 documented workaround for the single erratum of the Atmel AT697F 9570 processor. 9571 9572 Operating Systems 9573 9574 Android 9575 9576 * GCC now supports the Bionic C library and provides a convenient way 9577 of building native libraries and applications for the Android 9578 platform. Refer to the documentation of the -mandroid and -mbionic 9579 options for details on building native code. At the moment, Android 9580 support is enabled only for ARM. 9581 9582 Darwin/Mac OS X 9583 9584 * General 9585 + Initial support for CFString types has been added. 9586 This allows GCC to build projects including the system Core 9587 Foundation frameworks. The GCC Objective-C family supports 9588 CFString "toll-free bridged" as per the Mac OS X system tools. 9589 CFString is also recognized in the context of format 9590 attributes and arguments (see the documentation for format 9591 attributes for limitations). At present, 8-bit character types 9592 are supported. 9593 + Object file size reduction. 9594 The Darwin zeroed memory allocators have been re-written to 9595 make more use of .zerofill sections. For non-debug code, this 9596 can reduce object file size significantly. 9597 + Objective-C family 64-bit support (NeXT ABI 2). 9598 Initial support has been added to support 64-bit Objective-C 9599 code using the Darwin/OS X native (NeXT) runtime. ABI version 9600 2 will be selected automatically when 64-bit code is built. 9601 + Objective-C family 32-bit ABI 1. 9602 For 32-bit code ABI 1 is also now also allowed. At present it 9603 must be selected manually using -fobjc-abi-version=1 where 9604 applicable - i.e. on Darwin 9/10 (OS X 10.5/10.6). 9605 * x86 Architecture 9606 + The -mdynamic-no-pic option has been enabled. 9607 Code supporting -mdynamic-no-pic optimization has been added 9608 and is applicable to -m32 builds. The compiler bootstrap uses 9609 the option where appropriate. 9610 + The default value for -mtune= has been changed. 9611 Since Darwin systems are primarily Xeon, Core-2 or similar the 9612 default tuning has been changed to -mtune=core2. 9613 + Enable 128-bit long double (__float128) support on Darwin. 9614 * PPC Architecture 9615 + Darwin64 ABI. 9616 Several significant bugs have been fixed, such that GCC now 9617 produces code compatible with the Darwin64 PowerPC ABI. 9618 + libffi and boehm-gc. 9619 The Darwin ports of the libffi and boehm-gc libraries have 9620 been upgraded to include a Darwin64 implementation. This means 9621 that powerpc*-*-darwin9 platforms may now, for example, build 9622 Java applications with -m64 enabled. 9623 + Plug-in support has been enabled. 9624 + The -fsection-anchors option is now available although, 9625 presently, not heavily tested. 9626 9627 Solaris 2 9628 9629 New Features 9630 9631 * Support symbol versioning with the Sun linker. 9632 * Allow libstdc++ to leverage full ISO C99 support on Solaris 10+. 9633 * Support thread-local storage (TLS) with the Sun assembler on 9634 Solaris 2/x86. 9635 * Support TLS on Solaris 8/9 if prerequisites are met. 9636 * Support COMDAT group with the GNU assembler and recent Sun linker. 9637 * Support the Sun assembler visibility syntax. 9638 * Default Solaris 2/x86 to -march=pentium4 (Solaris 10+) resp. 9639 -march=pentiumpro (Solaris 8/9). 9640 * Don't use SSE on Solaris 8/9 x86 by default. 9641 * Enable 128-bit long double (__float128) support on Solaris 2/x86. 9642 9643 ABI Change 9644 9645 * Change the ABI for returning 8-byte vectors like __m64 in MMX 9646 registers on Solaris 10+/x86 to match the Sun Studio 12.1+ 9647 compilers. This is an incompatible change. If you use such types, 9648 you must either recompile all your code with the new compiler or 9649 use the new -mvect8-ret-in-mem option to remain compatible with 9650 previous versions of GCC and Sun Studio. 9651 9652 Windows x86/x86_64 9653 9654 * Initial support for decimal floating point. 9655 * Support for the __thiscall calling-convention. 9656 * Support for hot-patchable function prologues via the 9657 ms_hook_prologue attribute for x86_64 in addition to 32-bit x86. 9658 * Improvements of stack-probing and stack-allocation mechanisms. 9659 * Support of push/pop-macro pragma as preprocessor command. 9660 With #pragma push_macro("macro-name") the current definition of 9661 macro-name is saved and can be restored with #pragma 9662 pop_macro("macro-name") to its saved definition. 9663 * Enable 128-bit long double (__float128) support on MinGW and 9664 Cygwin. 9665 9666 Other significant improvements 9667 9668 Installation changes 9669 9670 * An install-strip make target is provided that installs stripped 9671 executables, and may install libraries with unneeded or debugging 9672 sections stripped. 9673 * On Power7 systems, there is a potential problem if you build the 9674 GCC compiler with a host compiler using options that enable the VSX 9675 instruction set generation. If the host compiler has been patched 9676 so that the vec_ld and vec_st builtin functions generate Altivec 9677 memory instructions instead of VSX memory instructions, then you 9678 should be able to build the compiler with VSX instruction 9679 generation. 9680 9681 Changes for GCC Developers 9682 9683 Note: these changes concern developers that develop GCC itself or 9684 software that integrates with GCC, such as plugins, and not the general 9685 GCC users. 9686 * The gengtype utility, which previously was internal to the GCC 9687 build process, has been enchanced to provide GC root information 9688 for plugins as necessary. 9689 * The old GC allocation interface of ggc_alloc and friends was 9690 replaced with a type-safe alternative. 9691 9692 GCC 4.6.1 9693 9694 This is the [19]list of problem reports (PRs) from GCC's bug tracking 9695 system that are known to be fixed in the 4.6.1 release. This list might 9696 not be complete (that is, it is possible that some PRs that have been 9697 fixed are not listed here). 9698 9699 GCC 4.6.2 9700 9701 This is the [20]list of problem reports (PRs) from GCC's bug tracking 9702 system that are known to be fixed in the 4.6.2 release. This list might 9703 not be complete (that is, it is possible that some PRs that have been 9704 fixed are not listed here). 9705 9706 GCC 4.6.3 9707 9708 This is the [21]list of problem reports (PRs) from GCC's bug tracking 9709 system that are known to be fixed in the 4.6.3 release. This list might 9710 not be complete (that is, it is possible that some PRs that have been 9711 fixed are not listed here). 9712 9713 GCC 4.6.4 9714 9715 This is the [22]list of problem reports (PRs) from GCC's bug tracking 9716 system that are known to be fixed in the 4.6.4 release. This list might 9717 not be complete (that is, it is possible that some PRs that have been 9718 fixed are not listed here). 9719 9720 9721 For questions related to the use of GCC, please consult these web 9722 pages and the [23]GCC manuals. If that fails, the 9723 [24]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 9724 web pages and the development of GCC are welcome on our developer 9725 list at [25]gcc (a] gcc.gnu.org. All of [26]our lists have public 9726 archives. 9727 9728 Copyright (C) [27]Free Software Foundation, Inc. Verbatim copying and 9729 distribution of this entire article is permitted in any medium, 9730 provided this notice is preserved. 9731 9732 These pages are [28]maintained by the GCC team. Last modified 9733 2023-01-18. 9734 9735 References 9736 9737 1. https://sourceware.org/bugzilla/show_bug.cgi?id=10401 9738 2. http://gcc.gnu.org/gcc-4.5/changes.html 9739 3. http://gcc.gnu.org/gcc-4.5/changes.html#obsoleted 9740 4. http://gcc.gnu.org/gcc-4.6/porting_to.html 9741 5. http://gcc.gnu.org/projects/lto/whopr.pdf 9742 6. https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#Warning-Options 9743 7. http://gcc.gnu.org/gcc-4.6/cxx0x_status.html 9744 8. https://gcc.gnu.org/PR43145 9745 9. https://gcc.gnu.org/PR43680 9746 10. https://gcc.gnu.org/PR33558 9747 11. https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#253 9748 12. https://gcc.gnu.org/onlinedocs/gcc-4.6.4/libstdc++/manual/manual/status.html#status.iso.200x 9749 13. https://gcc.gnu.org/onlinedocs/libstdc++/manual/debug_mode.html 9750 14. https://gcc.gnu.org/onlinedocs/libstdc++/manual/debug.html#debug.races 9751 15. https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html 9752 16. https://gcc.gnu.org/wiki/OOP 9753 17. https://gcc.gnu.org/wiki/Coarray 9754 18. https://gcc.gnu.org/onlinedocs/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfcoarray_007d-233 9755 19. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.6.1 9756 20. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.6.2 9757 21. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.6.3 9758 22. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.6.4 9759 23. https://gcc.gnu.org/onlinedocs/ 9760 24. mailto:gcc-help (a] gcc.gnu.org 9761 25. mailto:gcc (a] gcc.gnu.org 9762 26. https://gcc.gnu.org/lists.html 9763 27. https://www.fsf.org/ 9764 28. https://gcc.gnu.org/about.html 9765 ====================================================================== 9766 http://gcc.gnu.org/gcc-4.5/index.html 9767 9768 GCC 4.5 Release Series 9769 9770 (This release series is no longer supported.) 9771 9772 Jul 2, 2012 9773 9774 The [1]GNU project and the GCC developers are pleased to announce the 9775 release of GCC 4.5.4. 9776 9777 This release is a bug-fix release, containing fixes for regressions in 9778 GCC 4.5.3 relative to previous releases of GCC. 9779 9780 Release History 9781 9782 GCC 4.5.4 9783 Jul 2, 2012 ([2]changes) 9784 9785 GCC 4.5.3 9786 Apr 28, 2011 ([3]changes) 9787 9788 GCC 4.5.2 9789 Dec 16, 2010 ([4]changes) 9790 9791 GCC 4.5.1 9792 Jul 31, 2010 ([5]changes) 9793 9794 GCC 4.5.0 9795 April 14, 2010 ([6]changes) 9796 9797 References and Acknowledgements 9798 9799 GCC used to stand for the GNU C Compiler, but since the compiler 9800 supports several other languages aside from C, it now stands for the 9801 GNU Compiler Collection. 9802 9803 A list of [7]successful builds is updated as new information becomes 9804 available. 9805 9806 The GCC developers would like to thank the numerous people that have 9807 contributed new features, improvements, bug fixes, and other changes as 9808 well as test results to GCC. This [8]amazing group of volunteers is 9809 what makes GCC successful. 9810 9811 For additional information about GCC please refer to the [9]GCC project 9812 web site or contact the [10]GCC development mailing list. 9813 9814 To obtain GCC please use [11]our mirror sites or [12]our version 9815 control system. 9816 9817 9818 For questions related to the use of GCC, please consult these web 9819 pages and the [13]GCC manuals. If that fails, the 9820 [14]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 9821 web pages and the development of GCC are welcome on our developer 9822 list at [15]gcc (a] gcc.gnu.org. All of [16]our lists have public 9823 archives. 9824 9825 Copyright (C) [17]Free Software Foundation, Inc. Verbatim copying and 9826 distribution of this entire article is permitted in any medium, 9827 provided this notice is preserved. 9828 9829 These pages are [18]maintained by the GCC team. Last modified 9830 2022-10-26. 9831 9832 References 9833 9834 1. http://www.gnu.org/ 9835 2. http://gcc.gnu.org/gcc-4.5/changes.html 9836 3. http://gcc.gnu.org/gcc-4.5/changes.html 9837 4. http://gcc.gnu.org/gcc-4.5/changes.html 9838 5. http://gcc.gnu.org/gcc-4.5/changes.html 9839 6. http://gcc.gnu.org/gcc-4.5/changes.html 9840 7. http://gcc.gnu.org/gcc-4.5/buildstat.html 9841 8. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 9842 9. http://gcc.gnu.org/index.html 9843 10. mailto:gcc (a] gcc.gnu.org 9844 11. http://gcc.gnu.org/mirrors.html 9845 12. http://gcc.gnu.org/git.html 9846 13. https://gcc.gnu.org/onlinedocs/ 9847 14. mailto:gcc-help (a] gcc.gnu.org 9848 15. mailto:gcc (a] gcc.gnu.org 9849 16. https://gcc.gnu.org/lists.html 9850 17. https://www.fsf.org/ 9851 18. https://gcc.gnu.org/about.html 9852 ====================================================================== 9853 http://gcc.gnu.org/gcc-4.5/changes.html 9854 9855 GCC 4.5 Release Series 9856 Changes, New Features, and Fixes 9857 9858 Caveats 9859 9860 * GCC now requires the [1]MPC library in order to build. See the 9861 [2]prerequisites page for version requirements. 9862 * Support for a number of older systems and recently unmaintained or 9863 untested target ports of GCC has been declared obsolete in GCC 4.5. 9864 Unless there is activity to revive them, the next release of GCC 9865 will have their sources permanently removed. 9866 The following ports for individual systems on particular 9867 architectures have been obsoleted: 9868 + IRIX releases before 6.5 (mips-sgi-irix5*, 9869 mips-sgi-irix6.[0-4]) 9870 + Solaris 7 (*-*-solaris2.7) 9871 + Tru64 UNIX releases before V5.1 (alpha*-dec-osf4*, 9872 alpha-dec-osf5.0*) 9873 + Details for the IRIX, Solaris 7, and Tru64 UNIX obsoletions 9874 can be found in the [3]announcement. 9875 Support for the classic POWER architecture implemented in the 9876 original RIOS and RIOS2 processors of the old IBM RS/6000 product 9877 line has been obsoleted in the rs6000 port. This does not affect 9878 the new generation Power and PowerPC architectures. 9879 * Support has been removed for all the [4]configurations obsoleted in 9880 GCC 4.4. 9881 * Support has been removed for the protoize and unprotoize utilities, 9882 obsoleted in GCC 4.4. 9883 * Support has been removed for tuning for Itanium1 (Merced) variants. 9884 Note that code tuned for Itanium2 should also run correctly on 9885 Itanium1. 9886 * GCC now generates unwind info also for epilogues. DWARF debuginfo 9887 generated by GCC now uses more features of DWARF3 than before, and 9888 also some DWARF4 features. GDB older than 7.0 is not able to handle 9889 either of these, so to debug GCC 4.5 generated binaries or 9890 libraries GDB 7.0 or later is needed. You can disable use of DWARF4 9891 features with the -gdwarf-3 -gstrict-dwarf options, or use 9892 -gdwarf-2 -gstrict-dwarf to restrict GCC to just DWARF2, but 9893 epilogue unwind info is emitted unconditionally whenever unwind 9894 info is emitted. 9895 * On x86 targets, code containing floating-point calculations may run 9896 significantly more slowly when compiled with GCC 4.5 in strict C99 9897 conformance mode than they did with earlier GCC versions. This is 9898 due to stricter standard conformance of the compiler and can be 9899 avoided by using the option -fexcess-precision=fast; also see 9900 [5]below. 9901 * The function attribute noinline no longer prevents GCC from cloning 9902 the function. A new attribute noclone has been introduced for this 9903 purpose. Cloning a function means that it is duplicated and the new 9904 copy is specialized for certain contexts (for example when a 9905 parameter is a known constant). 9906 9907 General Optimizer Improvements 9908 9909 * The -save-temps now takes an optional argument. The -save-temps and 9910 -save-temps=cwd switches write the temporary files in the current 9911 working directory based on the original source file. The 9912 -save-temps=obj switch will write files into the directory 9913 specified with the -o option, and the intermediate filenames are 9914 based on the output file. This will allow the user to get the 9915 compiler intermediate files when doing parallel builds without two 9916 builds of the same filename located in different directories from 9917 interfering with each other. 9918 * Debugging dumps are now created in the same directory as the object 9919 file rather than in the current working directory. This allows the 9920 user to get debugging dumps when doing parallel builds without two 9921 builds of the same filename interfering with each other. 9922 * GCC has been integrated with the MPC library. This allows GCC to 9923 evaluate complex arithmetic at compile time [6]more accurately. It 9924 also allows GCC to evaluate calls to complex built-in math 9925 functions having constant arguments and replace them at compile 9926 time with their mathematically equivalent results. In doing so, GCC 9927 can generate correct results regardless of the math library 9928 implementation or floating point precision of the host platform. 9929 This also allows GCC to generate identical results regardless of 9930 whether one compiles in native or cross-compile configurations to a 9931 particular target. The following built-in functions take advantage 9932 of this new capability: cacos, cacosh, casin, casinh, catan, 9933 catanh, ccos, ccosh, cexp, clog, cpow, csin, csinh, csqrt, ctan, 9934 and ctanh. The float and long double variants of these functions 9935 (e.g. csinf and csinl) are also handled. 9936 * A new link-time optimizer has been added ([7]-flto). When this 9937 option is used, GCC generates a bytecode representation of each 9938 input file and writes it to specially-named sections in each object 9939 file. When the object files are linked together, all the function 9940 bodies are read from these named sections and instantiated as if 9941 they had been part of the same translation unit. This enables 9942 interprocedural optimizations to work across different files (and 9943 even different languages), potentially improving the performance of 9944 the generated code. To use the link-timer optimizer, -flto needs to 9945 be specified at compile time and during the final link. If the 9946 program does not require any symbols to be exported, it is possible 9947 to combine -flto and the experimental [8]-fwhopr with 9948 [9]-fwhole-program to allow the interprocedural optimizers to use 9949 more aggressive assumptions. 9950 * The automatic parallelization pass was enhanced to support 9951 parallelization of outer loops. 9952 * Automatic parallelization can be enabled as part of Graphite. In 9953 addition to -ftree-parallelize-loops=, specify 9954 -floop-parallelize-all to enable the Graphite-based optimization. 9955 * The infrastructure for optimizing based on [10]restrict qualified 9956 pointers has been rewritten and should result in code generation 9957 improvements. Optimizations based on restrict qualified pointers 9958 are now also available when using -fno-strict-aliasing. 9959 * There is a new optimization pass that attempts to change prototype 9960 of functions to avoid unused parameters, pass only relevant parts 9961 of structures and turn arguments passed by reference to arguments 9962 passed by value when possible. It is enabled by -O2 and above as 9963 well as -Os and can be manually invoked using the new command-line 9964 switch -fipa-sra. 9965 * GCC now optimize exception handling code. In particular cleanup 9966 regions that are proved to not have any effect are optimized out. 9967 9968 New Languages and Language specific improvements 9969 9970 All languages 9971 9972 * The -fshow-column option is now on by default. This means error 9973 messages now have a column associated with them. 9974 9975 Ada 9976 9977 * Compilation of programs heavily using discriminated record types 9978 with variant parts has been sped up and generates more compact 9979 code. 9980 * Stack checking now works reasonably well on most plaforms. In some 9981 specific cases, stack overflows may still fail to be detected, but 9982 a compile-time warning will be issued for these cases. 9983 9984 C family 9985 9986 * If a header named in a #include directive is not found, the 9987 compiler exits immediately. This avoids a cascade of errors arising 9988 from declarations expected to be found in that header being 9989 missing. 9990 * A new built-in function __builtin_unreachable() has been added that 9991 tells the compiler that control will never reach that point. It may 9992 be used after asm statements that terminate by transferring control 9993 elsewhere, and in other places that are known to be unreachable. 9994 * The -Wlogical-op option now warns for logical expressions such as 9995 (c == 1 && c == 2) and (c != 1 || c != 2), which are likely to be 9996 mistakes. This option is disabled by default. 9997 * An asm goto feature has been added to allow asm statements that 9998 jump to C labels. 9999 * C++0x raw strings are supported for C++ and for C with -std=gnu99. 10000 * The deprecated attribute now takes an optional string argument, for 10001 example, __attribute__((deprecated("text string"))), that will be 10002 printed together with the deprecation warning. 10003 10004 C 10005 10006 * The -Wenum-compare option, which warns when comparing values of 10007 different enum types, now works for C. It formerly only worked for 10008 C++. This warning is enabled by -Wall. It may be avoided by using a 10009 type cast. 10010 * The -Wcast-qual option now warns about casts which are unsafe in 10011 that they permit const-correctness to be violated without further 10012 warnings. Specifically, it warns about cases where a qualifier is 10013 added when all the lower types are not const. For example, it warns 10014 about a cast from char ** to const char **. 10015 * The -Wc++-compat option is significantly improved. It issues new 10016 warnings for: 10017 + Using C++ reserved operator names as identifiers. 10018 + Conversions to enum types without explicit casts. 10019 + Using va_arg with an enum type. 10020 + Using different enum types in the two branches of ?:. 10021 + Using ++ or -- on a variable of enum type. 10022 + Using the same name as both a struct, union or enum tag and a 10023 typedef, unless the typedef refers to the tagged type itself. 10024 + Using a struct, union, or enum which is defined within another 10025 struct or union. 10026 + A struct field defined using a typedef if there is a field in 10027 the struct, or an enclosing struct, whose name is the typedef 10028 name. 10029 + Duplicate definitions at file scope. 10030 + Uninitialized const variables. 10031 + A global variable with an anonymous struct, union, or enum 10032 type. 10033 + Using a string constant to initialize a char array whose size 10034 is the length of the string. 10035 * The new -Wjump-misses-init option warns about cases where a goto or 10036 switch skips the initialization of a variable. This sort of branch 10037 is an error in C++ but not in C. This warning is enabled by 10038 -Wc++-compat. 10039 * GCC now ensures that a C99-conforming <stdint.h> is present on most 10040 targets, and uses information about the types in this header to 10041 implement the Fortran bindings to those types. GCC does not ensure 10042 the presence of such a header, and does not implement the Fortran 10043 bindings, on the following targets: NetBSD, VxWorks, VMS, 10044 SymbianOS, WinCE, LynxOS, Netware, QNX, Interix, TPF. 10045 * GCC now implements C90- and C99-conforming rules for constant 10046 expressions. This may cause warnings or errors for some code using 10047 expressions that can be folded to a constant but are not constant 10048 expressions as defined by ISO C. 10049 * All known target-independent C90 and C90 Amendment 1 conformance 10050 bugs, and all known target-independent C99 conformance bugs not 10051 related to floating point or extended identifiers, have been fixed. 10052 * The C decimal floating point support now includes support for the 10053 FLOAT_CONST_DECIMAL64 pragma. 10054 * The named address space feature from ISO/IEC TR 18037 is now 10055 supported. This is currently only implemented for the SPU 10056 processor. 10057 10058 C++ 10059 10060 * Improved [11]experimental support for the upcoming C++0x ISO C++ 10061 standard, including support for raw strings, lambda expressions and 10062 explicit type conversion operators. 10063 * When printing the name of a class template specialization, G++ will 10064 now omit any template arguments which come from default template 10065 arguments. This behavior (and the pretty-printing of function 10066 template specializations as template signature and arguments) can 10067 be disabled with the -fno-pretty-templates option. 10068 * Access control is now applied to typedef names used in a template, 10069 which may cause G++ to reject some ill-formed code that was 10070 accepted by earlier releases. The -fno-access-control option can be 10071 used as a temporary workaround until the code is corrected. 10072 * Compilation time for code that uses templates should now scale 10073 linearly with the number of instantiations rather than 10074 quadratically, as template instantiations are now looked up using 10075 hash tables. 10076 * Declarations of functions that look like builtin declarations of 10077 library functions are only considered to be redeclarations if they 10078 are declared with extern "C". This may cause problems with code 10079 that omits extern "C" on hand-written declarations of C library 10080 functions such as abort or memcpy. Such code is ill-formed, but was 10081 accepted by earlier releases. 10082 * Diagnostics that used to complain about passing non-POD types to 10083 ... or jumping past the declaration of a non-POD variable now check 10084 for triviality rather than PODness, as per C++0x. 10085 * In C++0x mode local and anonymous classes are now allowed as 10086 template arguments, and in declarations of variables and functions 10087 with linkage, so long as any such declaration that is used is also 10088 defined ([12]DR 757). 10089 * Labels may now have attributes, as has been permitted for a while 10090 in C. This is only permitted when the label definition and the 10091 attribute specifier is followed by a semicolon--i.e., the label 10092 applies to an empty statement. The only useful attribute for a 10093 label is unused. 10094 * G++ now implements [13]DR 176. Previously G++ did not support using 10095 the injected-class-name of a template base class as a type name, 10096 and lookup of the name found the declaration of the template in the 10097 enclosing scope. Now lookup of the name finds the 10098 injected-class-name, which can be used either as a type or as a 10099 template, depending on whether or not the name is followed by a 10100 template argument list. As a result of this change, some code that 10101 was previously accepted may be ill-formed because 10102 1. The injected-class-name is not accessible because it's from a 10103 private base, or 10104 2. The injected-class-name cannot be used as an argument for a 10105 template template parameter. 10106 In either of these cases, the code can be fixed by adding a 10107 nested-name-specifier to explicitly name the template. The first 10108 can be worked around with -fno-access-control; the second is only 10109 rejected with -pedantic. 10110 * A new standard mangling for SIMD vector types has been added, to 10111 avoid name clashes on systems with vectors of varying length. By 10112 default the compiler still uses the old mangling, but emits aliases 10113 with the new mangling on targets that support strong aliases. Users 10114 can switch over entirely to the new mangling with -fabi-version=4 10115 or -fabi-version=0. -Wabi will now warn about code that uses the 10116 old mangling. 10117 * The command-line option -ftemplate-depth-N is now written as 10118 -ftemplate-depth=N and the old form is deprecated. 10119 * Conversions between NULL and non-pointer types are now warned by 10120 default. The new option -Wno-conversion-null disables these 10121 warnings. Previously these warnings were only available when using 10122 -Wconversion explicitly. 10123 10124 Runtime Library (libstdc++) 10125 10126 * Improved experimental support for the upcoming ISO C++ standard, 10127 C++0x, including: 10128 + Support for <future>, <functional>, and <random>. 10129 + Existing facilities now exploit explicit operators and the 10130 newly implemented core C++0x features. 10131 + The header <cstdatomic> has been renamed to <atomic>. 10132 * An experimental [14]profile mode has been added. This is an 10133 implementation of many C++ standard library constructs with an 10134 additional analysis layer that gives performance improvement advice 10135 based on recognition of suboptimal usage patterns. For example, 10136 #include <vector> 10137 int main() 10138 { 10139 std::vector<int> v; 10140 for (int k = 0; k < 1024; ++k) 10141 v.insert(v.begin(), k); 10142 } 10143 10144 When instrumented via the profile mode, can return suggestions 10145 about the initial size and choice of the container used as follows: 10146 vector-to-list: improvement = 5: call stack = 0x804842c ... 10147 : advice = change std::vector to std::list 10148 vector-size: improvement = 3: call stack = 0x804842c ... 10149 : advice = change initial container size from 0 to 1024 10150 10151 These constructs can be substituted for the normal libstdc++ 10152 constructs on a piecemeal basis, or all existing components can be 10153 transformed via the -D_GLIBCXX_PROFILE macro. 10154 * [15]Support for decimal floating-point arithmetic (aka ISO C++ TR 10155 24733) has been added. This support is in header file 10156 <decimal/decimal>, uses namespace std::decimal, and includes 10157 classes decimal32, decimal64, and decimal128. 10158 * Sources have been audited for application of function attributes 10159 nothrow, const, pure, and noreturn. 10160 * Python pretty-printers have been added for many standard library 10161 components that simplify the internal representation and present a 10162 more intuitive view of components when used with 10163 appropriately-advanced versions of GDB. For more information, 10164 please consult the more [16]detailed description. 10165 * The default behavior for comparing typeinfo names has changed, so 10166 in <typeinfo>, __GXX_MERGED_TYPEINFO_NAMES now defaults to zero. 10167 * The new -static-libstdc++ option directs g++ to link the C++ 10168 library statically, even if the default would normally be to link 10169 it dynamically. 10170 10171 Fortran 10172 10173 * The COMMON default padding has been changed - instead of adding the 10174 padding before a variable it is now added afterwards, which 10175 increases the compatibility with other vendors and helps to obtain 10176 the correct output in some cases. Cf. also the -falign-commons 10177 option ([17]added in 4.4). 10178 * The -finit-real= option now also supports the value snan for 10179 signaling not-a-number; to be effective, one additionally needs to 10180 enable trapping (e.g. via -ffpe-trap=). Note: Compile-time 10181 optimizations can turn a signaling NaN into a quiet one. 10182 * The new option -fcheck= has been added with the options bounds, 10183 array-temps, do, pointer, and recursive. The bounds and array-temps 10184 options are equivalent to -fbounds-check and 10185 -fcheck-array-temporaries. The do option checks for invalid 10186 modification of loop iteration variables, and the recursive option 10187 tests for recursive calls to subroutines/functions which are not 10188 marked as recursive. With pointer pointer association checks in 10189 calls are performed; however, neither undefined pointers nor 10190 pointers in expressions are handled. Using -fcheck=all enables all 10191 these run-time checks. 10192 * The run-time checking -fcheck=bounds now warns about invalid string 10193 lengths of character dummy arguments. Additionally, more 10194 compile-time checks have been added. 10195 * The new option [18]-fno-protect-parens has been added; if set, the 10196 compiler may reorder REAL and COMPLEX expressions without regard to 10197 parentheses. 10198 * GNU Fortran no longer links against libgfortranbegin. As before, 10199 MAIN__ (assembler symbol name) is the actual Fortran main program, 10200 which is invoked by the main function. However, main is now 10201 generated and put in the same object file as MAIN__. For the time 10202 being, libgfortranbegin still exists for backward compatibility. 10203 For details see the new [19]Mixed-Language Programming chapter in 10204 the manual. 10205 * The I/O library was restructured for performance and cleaner code. 10206 * Array assignments and WHERE are now run in parallel when OpenMP's 10207 WORKSHARE is used. 10208 * The experimental option -fwhole-file was added. The option allows 10209 whole-file checking of procedure arguments and allows for better 10210 optimizations. It can also be used with -fwhole-program, which is 10211 now also supported in gfortran. 10212 * More Fortran 2003 and Fortran 2008 mathematical functions can now 10213 be used as initialization expressions. 10214 * Some extended attributes such as STDCALL are now supported via the 10215 [20]GCC$ compiler directive. 10216 * For Fortran 77 compatibility: If -fno-sign-zero is used, the SIGN 10217 intrinsic behaves now as if zero were always positive. 10218 * For legacy compatibiliy: On Cygwin and MinGW, the special files 10219 CONOUT$ and CONIN$ (and CONERR$ which maps to CONOUT$) are now 10220 supported. 10221 * Fortran 2003 support has been extended: 10222 + Procedure-pointer function results and procedure-pointer 10223 components (including PASS), 10224 + allocatable scalars (experimental), 10225 + DEFERRED type-bound procedures, 10226 + the ERRMSG= argument of the ALLOCATE and DEALLOCATE statements 10227 have been implemented. 10228 + The ALLOCATE statement supports type-specs and the SOURCE= 10229 argument. 10230 + OPERATOR(*) and ASSIGNMENT(=) are now allowed as GENERIC 10231 type-bound procedure (i.e. as type-bound operators). 10232 + Rounding (ROUND=, RZ, ...) for output is now supported. 10233 + The INT_FAST{8,16,32,64,128}_T kind type parameters of the 10234 intrinsic module ISO_C_BINDING are now supported, except for 10235 the targets listed above as ones where GCC does not have 10236 <stdint.h> type information. 10237 + Extensible derived types with type-bound procedure or 10238 procedure pointer with PASS attribute now have to use CLASS in 10239 line with the Fortran 2003 standard; the workaround to use 10240 TYPE is no longer supported. 10241 + [21]Experimental, incomplete support for polymorphism, 10242 including CLASS, SELECT TYPE and dynamic dispatch of 10243 type-bound procedure calls. Some features do not work yet such 10244 as unlimited polymorphism (CLASS(*)). 10245 * Fortran 2008 support has been extended: 10246 + The OPEN statement now supports the NEWUNIT= option, which 10247 returns a unique file unit, thus preventing inadvertent use of 10248 the same unit in different parts of the program. 10249 + Support for unlimited format items has been added. 10250 + The INT{8,16,32} and REAL{32,64,128} kind type parameters of 10251 the intrinsic module ISO_FORTRAN_ENV are now supported. 10252 + Using complex arguments with TAN, SINH, COSH, TANH, ASIN, 10253 ACOS, and ATAN is now possible; the functions ASINH, ACOSH, 10254 and ATANH have been added (for real and complex arguments) and 10255 ATAN(Y,X) is now an alias for ATAN2(Y,X). 10256 + The BLOCK construct has been implemented. 10257 10258 New Targets and Target Specific Improvements 10259 10260 AIX 10261 10262 * Full cross-toolchain support now available with GNU Binutils 10263 10264 ARM 10265 10266 * GCC now supports the Cortex-M0 and Cortex-A5 processors. 10267 * GCC now supports the ARM v7E-M architecture. 10268 * GCC now supports VFPv4-based FPUs and FPUs with 10269 single-precision-only VFP. 10270 * GCC has many improvements to optimization for other ARM processors, 10271 including scheduling support for the integer pipeline on Cortex-A9. 10272 * GCC now supports the IEEE 754-2008 half-precision floating-point 10273 type, and a variant ARM-specific half-precision type. This type is 10274 specified using __fp16, with the layout determined by 10275 -mfp16-format. With appropriate -mfpu options, the Cortex-A9 and 10276 VFPv4 half-precision instructions will be used. 10277 * GCC now supports the variant of AAPCS that uses VFP registers for 10278 parameter passing and return values. 10279 10280 AVR 10281 10282 * The -mno-tablejump option has been removed because it has the same 10283 effect as the -fno-jump-tables option. 10284 * Added support for these new AVR devices: 10285 + ATmega8U2 10286 + ATmega16U2 10287 + ATmega32U2 10288 10289 IA-32/x86-64 10290 10291 * GCC now will set the default for -march= based on the configure 10292 target. 10293 * GCC now supports handling floating-point excess precision arising 10294 from use of the x87 floating-point unit in a way that conforms to 10295 ISO C99. This is enabled with -fexcess-precision=standard and with 10296 standards conformance options such as -std=c99, and may be disabled 10297 using -fexcess-precision=fast. 10298 * Support for the Intel Atom processor is now available through the 10299 -march=atom and -mtune=atom options. 10300 * A new -mcrc32 option is now available to enable crc32 intrinsics. 10301 * A new -mmovbe option is now available to enable GCC to use the 10302 movbe instruction to implement __builtin_bswap32 and 10303 __builtin_bswap64. 10304 * SSE math now can be enabled by default at configure time with the 10305 new --with-fpmath=sse option. 10306 * There is a new intrinsic header file, <x86intrin.h>. It should be 10307 included before using any IA-32/x86-64 intrinsics. 10308 * Support for the XOP, FMA4, and LWP instruction sets for the AMD 10309 Orochi processors are now available with the -mxop, -mfma4, and 10310 -mlwp options. 10311 * The -mabm option enables GCC to use the popcnt and lzcnt 10312 instructions on AMD processors. 10313 * The -mpopcnt option enables GCC to use the popcnt instructions on 10314 both AMD and Intel processors. 10315 10316 M68K/ColdFire 10317 10318 * GCC now supports ColdFire 51xx, 5221x, 5225x, 52274, 52277, 5301x 10319 and 5441x devices. 10320 * GCC now supports thread-local storage (TLS) on M68K and ColdFire 10321 processors. 10322 10323 MeP 10324 10325 Support has been added for the Toshiba Media embedded Processor (MeP, 10326 or mep-elf) embedded target. 10327 10328 MIPS 10329 10330 * GCC now supports MIPS 1004K processors. 10331 * GCC can now be configured with options --with-arch-32, 10332 --with-arch-64, --with-tune-32 and --with-tune-64 to control the 10333 default optimization separately for 32-bit and 64-bit modes. 10334 * MIPS targets now support an alternative _mcount interface, in which 10335 register $12 points to the function's save slot for register $31. 10336 This interface is selected by the -mcount-ra-address option; see 10337 the documentation for more details. 10338 * GNU/Linux targets can now generate read-only .eh_frame sections. 10339 This optimization requires GNU binutils 2.20 or above, and is only 10340 available if GCC is configured with a suitable version of binutils. 10341 * GNU/Linux targets can now attach special relocations to indirect 10342 calls, so that the linker can turn them into direct jumps or 10343 branches. This optimization requires GNU binutils 2.20 or later, 10344 and is automatically selected if GCC is configured with an 10345 appropriate version of binutils. It can be explicitly enabled or 10346 disabled using the -mrelax-pic-calls command-line option. 10347 * GCC now generates more heavily-optimized atomic operations on 10348 Octeon processors. 10349 * MIPS targets now support the -fstack-protector option. 10350 * GCC now supports an -msynci option, which specifies that synci is 10351 enough to flush the instruction cache, without help from the 10352 operating system. GCC uses this information to optimize 10353 automatically-generated cache flush operations, such as those used 10354 for nested functions in C. There is also a --with-synci 10355 configure-time option, which makes -msynci the default. 10356 * GCC supports four new function attributes for interrupt handlers: 10357 interrupt, use_shadow_register_set, keep_interrupts_masked and 10358 use_debug_exception_return. See the documentation for more details 10359 about these attributes. 10360 10361 RS/6000 (POWER/PowerPC) 10362 10363 * GCC now supports the Power ISA 2.06, which includes the VSX 10364 instructions that add vector 64-bit floating point support, new 10365 population count instructions, and conversions between floating 10366 point and unsigned types. 10367 * Support for the power7 processor is now available through the 10368 -mcpu=power7 and -mtune=power7. 10369 * GCC will now vectorize loops that contain simple math functions 10370 like copysign when generating code for altivec or VSX targets. 10371 * Support for the A2 processor is now available through the -mcpu=a2 10372 and -mtune=a2 options. 10373 * Support for the 476 processor is now available through the 10374 -mcpu={476,476fp} and -mtune={476,476fp} options. 10375 * Support for the e500mc64 processor is now available through the 10376 -mcpu=e500mc64 and -mtune=e500mc64 options. 10377 * GCC can now be configured with options --with-cpu-32, 10378 --with-cpu-64, --with-tune-32 and --with-tune-64 to control the 10379 default optimization separately for 32-bit and 64-bit modes. 10380 * Starting with GCC 4.5.4, vectors of type vector long long or vector 10381 long are passed and returned in the same method as other vectors 10382 with the VSX instruction set. Previously the GCC compiler did not 10383 adhere to the ABI for 128-bit vectors with 64-bit integer base 10384 types (PR 48857). This is also fixed in the GCC 4.6.1 release. 10385 10386 RX 10387 10388 Support has been added for the Renesas RX Processor (rx-elf) target. 10389 10390 Operating Systems 10391 10392 Windows (Cygwin and MinGW) 10393 10394 * GCC now installs all the major language runtime libraries as DLLs 10395 when configured with the --enable-shared option. 10396 * GCC now makes use of the new support for aligned common variables 10397 in versions of binutils >= 2.20 to fix bugs in the support for SSE 10398 data types. 10399 * Improvements to the libffi support library increase the reliability 10400 of code generated by GCJ on all Windows platforms. Libgcj is 10401 enabled by default for the first time. 10402 * Libtool improvements simplify installation by placing the generated 10403 DLLs in the correct binaries directory. 10404 * Numerous other minor bugfixes and improvements, and substantial 10405 enhancements to the Fortran language support library. 10406 10407 > 10408 10409 Other significant improvements 10410 10411 Plugins 10412 10413 * It is now possible to extend the compiler without having to modify 10414 its source code. A new option -fplugin=file.so tells GCC to load 10415 the shared object file.so and execute it as part of the compiler. 10416 The internal documentation describes the details on how plugins can 10417 interact with the compiler. 10418 10419 Installation changes 10420 10421 * The move to newer autotools changed default installation 10422 directories and switches to control them: The --with-datarootdir, 10423 --with-docdir, --with-pdfdir, and --with-htmldir switches are not 10424 used any more. Instead, you can now use --datarootdir, --docdir, 10425 --htmldir, and --pdfdir. The default installation directories have 10426 changed as follows according to the GNU Coding Standards: 10427 10428 datarootdir read-only architecture-independent data root [PREFIX/share] 10429 localedir locale-specific message catalogs [DATAROOTDIR/locale] 10430 docdir documentation root [DATAROOTDIR/doc/PACKAGE] 10431 htmldir html documentation [DOCDIR] 10432 dvidir dvi documentation [DOCDIR] 10433 pdfdir pdf documentation [DOCDIR] 10434 psdir ps documentation [DOCDIR] 10435 The following variables have new default values: 10436 10437 datadir read-only architecture-independent data [DATAROOTDIR] 10438 infodir info documentation [DATAROOTDIR/info] 10439 mandir man documentation [DATAROOTDIR/man] 10440 10441 GCC 4.5.1 10442 10443 This is the [22]list of problem reports (PRs) from GCC's bug tracking 10444 system that are known to be fixed in the 4.5.1 release. This list might 10445 not be complete (that is, it is possible that some PRs that have been 10446 fixed are not listed here). 10447 10448 All languages 10449 10450 * GCC's new link-time optimizer ([23]-flto) now also works on a few 10451 non-ELF targets: 10452 + Cygwin (*-cygwin*) 10453 + MinGW (*-mingw*) 10454 + Darwin on x86-64 (x86_64-apple-darwin*) 10455 LTO is not enabled by default for these targets. To enable LTO, you 10456 should configure with the --enable-lto option. 10457 10458 GCC 4.5.2 10459 10460 This is the [24]list of problem reports (PRs) from GCC's bug tracking 10461 system that are known to be fixed in the 4.5.2 release. This list might 10462 not be complete (that is, it is possible that some PRs that have been 10463 fixed are not listed here). 10464 10465 GCC 4.5.3 10466 10467 This is the [25]list of problem reports (PRs) from GCC's bug tracking 10468 system that are known to be fixed in the 4.5.3 release. This list might 10469 not be complete (that is, it is possible that some PRs that have been 10470 fixed are not listed here). 10471 10472 On the PowerPC compiler, the Altivec builtin functions vec_ld and 10473 vec_st have been modified to generate the Altivec memory instructions 10474 LVX and STVX, even if the -mvsx option is used. In the initial GCC 4.5 10475 release, these builtin functions were changed to generate VSX memory 10476 reference instructions instead of Altivec memory instructions, but 10477 there are differences between the two instructions. If the VSX 10478 instruction set is available, you can now use the new builtin functions 10479 vec_vsx_ld and vec_vsx_st which always generates the VSX memory 10480 instructions. 10481 10482 GCC 4.5.4 10483 10484 This is the [26]list of problem reports (PRs) from GCC's bug tracking 10485 system that are known to be fixed in the 4.5.4 release. This list might 10486 not be complete (that is, it is possible that some PRs that have been 10487 fixed are not listed here). 10488 10489 10490 For questions related to the use of GCC, please consult these web 10491 pages and the [27]GCC manuals. If that fails, the 10492 [28]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 10493 web pages and the development of GCC are welcome on our developer 10494 list at [29]gcc (a] gcc.gnu.org. All of [30]our lists have public 10495 archives. 10496 10497 Copyright (C) [31]Free Software Foundation, Inc. Verbatim copying and 10498 distribution of this entire article is permitted in any medium, 10499 provided this notice is preserved. 10500 10501 These pages are [32]maintained by the GCC team. Last modified 10502 2023-01-15. 10503 10504 References 10505 10506 1. https://www.multiprecision.org/mpc/ 10507 2. https://gcc.gnu.org/install/prerequisites.html 10508 3. https://gcc.gnu.org/ml/gcc/2010-01/msg00510.html 10509 4. http://gcc.gnu.org/gcc-4.4/changes.html#obsoleted 10510 5. http://gcc.gnu.org/gcc-4.5/changes.html#x86 10511 6. https://gcc.gnu.org/PR30789 10512 7. https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-flto-801 10513 8. https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-fwhopr-802 10514 9. https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-fwhole-program-800 10515 10. https://gcc.gnu.org/onlinedocs/gcc/Restricted-Pointers.html 10516 11. http://gcc.gnu.org/gcc-4.5/cxx0x_status.html 10517 12. https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#757 10518 13. https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#176 10519 14. https://gcc.gnu.org/onlinedocs/libstdc++/manual/profile_mode.html 10520 15. https://gcc.gnu.org/onlinedocs/libstdc++/manual/status.html#status.iso.tr24733 10521 16. https://sourceware.org/gdb/wiki/STLSupport 10522 17. http://gcc.gnu.org/gcc-4.4/changes.html 10523 18. https://gcc.gnu.org/onlinedocs/gfortran/Code-Gen-Options.html 10524 19. https://gcc.gnu.org/onlinedocs/gfortran/Mixed-Language-Programming.html 10525 20. https://gcc.gnu.org/onlinedocs/gfortran/GNU-Fortran-Compiler-Directives.html 10526 21. https://gcc.gnu.org/wiki/OOP 10527 22. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.5.1 10528 23. https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-flto-801 10529 24. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.5.2 10530 25. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.5.3 10531 26. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.5.4 10532 27. https://gcc.gnu.org/onlinedocs/ 10533 28. mailto:gcc-help (a] gcc.gnu.org 10534 29. mailto:gcc (a] gcc.gnu.org 10535 30. https://gcc.gnu.org/lists.html 10536 31. https://www.fsf.org/ 10537 32. https://gcc.gnu.org/about.html 10538 ====================================================================== 10539 http://gcc.gnu.org/gcc-4.4/index.html 10540 10541 GCC 4.4 Release Series 10542 10543 This release series is no longer maintained. 10544 10545 March 13, 2012 10546 10547 The [1]GNU project and the GCC developers are pleased to announce the 10548 release of GCC 4.4.7. 10549 10550 This release is a bug-fix release, containing fixes for regressions in 10551 GCC 4.4.6 relative to previous releases of GCC. 10552 10553 Release History 10554 10555 GCC 4.4.7 10556 March 13, 2012 ([2]changes) 10557 10558 GCC 4.4.6 10559 April 16, 2011 ([3]changes) 10560 10561 GCC 4.4.5 10562 October 1, 2010 ([4]changes) 10563 10564 GCC 4.4.4 10565 April 29, 2010 ([5]changes) 10566 10567 GCC 4.4.3 10568 January 21, 2010 ([6]changes) 10569 10570 GCC 4.4.2 10571 October 15, 2009 ([7]changes) 10572 10573 GCC 4.4.1 10574 July 22, 2009 ([8]changes) 10575 10576 GCC 4.4.0 10577 April 21, 2009 ([9]changes) 10578 10579 References and Acknowledgements 10580 10581 GCC used to stand for the GNU C Compiler, but since the compiler 10582 supports several other languages aside from C, it now stands for the 10583 GNU Compiler Collection. 10584 10585 A list of [10]successful builds is updated as new information becomes 10586 available. 10587 10588 The GCC developers would like to thank the numerous people that have 10589 contributed new features, improvements, bug fixes, and other changes as 10590 well as test results to GCC. This [11]amazing group of volunteers is 10591 what makes GCC successful. 10592 10593 For additional information about GCC please refer to the [12]GCC 10594 project web site or contact the [13]GCC development mailing list. 10595 10596 To obtain GCC please use [14]our mirror sites or [15]our version 10597 control system. 10598 10599 10600 For questions related to the use of GCC, please consult these web 10601 pages and the [16]GCC manuals. If that fails, the 10602 [17]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 10603 web pages and the development of GCC are welcome on our developer 10604 list at [18]gcc (a] gcc.gnu.org. All of [19]our lists have public 10605 archives. 10606 10607 Copyright (C) [20]Free Software Foundation, Inc. Verbatim copying and 10608 distribution of this entire article is permitted in any medium, 10609 provided this notice is preserved. 10610 10611 These pages are [21]maintained by the GCC team. Last modified 10612 2022-10-26. 10613 10614 References 10615 10616 1. http://www.gnu.org/ 10617 2. http://gcc.gnu.org/gcc-4.4/changes.html 10618 3. http://gcc.gnu.org/gcc-4.4/changes.html 10619 4. http://gcc.gnu.org/gcc-4.4/changes.html 10620 5. http://gcc.gnu.org/gcc-4.4/changes.html 10621 6. http://gcc.gnu.org/gcc-4.4/changes.html 10622 7. http://gcc.gnu.org/gcc-4.4/changes.html 10623 8. http://gcc.gnu.org/gcc-4.4/changes.html 10624 9. http://gcc.gnu.org/gcc-4.4/changes.html 10625 10. http://gcc.gnu.org/gcc-4.4/buildstat.html 10626 11. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 10627 12. http://gcc.gnu.org/index.html 10628 13. mailto:gcc (a] gcc.gnu.org 10629 14. http://gcc.gnu.org/mirrors.html 10630 15. http://gcc.gnu.org/git.html 10631 16. https://gcc.gnu.org/onlinedocs/ 10632 17. mailto:gcc-help (a] gcc.gnu.org 10633 18. mailto:gcc (a] gcc.gnu.org 10634 19. https://gcc.gnu.org/lists.html 10635 20. https://www.fsf.org/ 10636 21. https://gcc.gnu.org/about.html 10637 ====================================================================== 10638 http://gcc.gnu.org/gcc-4.4/changes.html 10639 10640 GCC 4.4 Release Series 10641 Changes, New Features, and Fixes 10642 10643 The latest release in the 4.4 release series is [1]GCC 4.4.7. 10644 10645 Caveats 10646 10647 * __builtin_stdarg_start has been completely removed from GCC. 10648 Support for <varargs.h> had been deprecated since GCC 4.0. Use 10649 __builtin_va_start as a replacement. 10650 * Some of the errors issued by the C++ front end that could be 10651 downgraded to warnings in previous releases by using -fpermissive 10652 are now warnings by default. They can be converted into errors by 10653 using -pedantic-errors. 10654 * Use of the cpp assertion extension will now emit a warning when 10655 -Wdeprecated or -pedantic is used. This extension has been 10656 deprecated for many years, but never warned about. 10657 * Packed bit-fields of type char were not properly bit-packed on many 10658 targets prior to GCC 4.4. On these targets, the fix in GCC 4.4 10659 causes an ABI change. For example there is no longer a 4-bit 10660 padding between field a and b in this structure: 10661 struct foo 10662 { 10663 char a:4; 10664 char b:8; 10665 } __attribute__ ((packed)); 10666 There is a new warning to help identify fields that are affected: 10667 foo.c:5: note: Offset of packed bit-field 'b' has changed in GCC 4.4 10668 The warning can be disabled with -Wno-packed-bitfield-compat. 10669 * On ARM EABI targets, the C++ mangling of the va_list type has been 10670 changed to conform to the current revision of the EABI. This does 10671 not affect the libstdc++ library included with GCC. 10672 * The SCOUNT and POS bits of the MIPS DSP control register are now 10673 treated as global. Previous versions of GCC treated these fields as 10674 call-clobbered instead. 10675 * The MIPS port no longer recognizes the h asm constraint. It was 10676 necessary to remove this constraint in order to avoid generating 10677 unpredictable code sequences. 10678 One of the main uses of the h constraint was to extract the high 10679 part of a multiplication on 64-bit targets. For example: 10680 asm ("dmultu\t%1,%2" : "=h" (result) : "r" (x), "r" (y)); 10681 You can now achieve the same effect using 128-bit types: 10682 typedef unsigned int uint128_t __attribute__((mode(TI))); 10683 result = ((uint128_t) x * y) >> 64; 10684 The second sequence is better in many ways. For example, if x and y 10685 are constants, the compiler can perform the multiplication at 10686 compile time. If x and y are not constants, the compiler can 10687 schedule the runtime multiplication better than it can schedule an 10688 asm statement. 10689 * Support for a number of older systems and recently unmaintained or 10690 untested target ports of GCC has been declared obsolete in GCC 4.4. 10691 Unless there is activity to revive them, the next release of GCC 10692 will have their sources permanently removed. 10693 The following ports for individual systems on particular 10694 architectures have been obsoleted: 10695 + Generic a.out on IA32 and m68k (i[34567]86-*-aout*, 10696 m68k-*-aout*) 10697 + Generic COFF on ARM, H8300, IA32, m68k and SH (arm-*-coff*, 10698 armel-*-coff*, h8300-*-*, i[34567]86-*-coff*, m68k-*-coff*, 10699 sh-*-*). This does not affect other more specific targets 10700 using the COFF object format on those architectures, or the 10701 more specific H8300 and SH targets (h8300-*-rtems*, 10702 h8300-*-elf*, sh-*-elf*, sh-*-symbianelf*, sh-*-linux*, 10703 sh-*-netbsdelf*, sh-*-rtems*, sh-wrs-vxworks). 10704 + 2BSD on PDP-11 (pdp11-*-bsd) 10705 + AIX 4.1 and 4.2 on PowerPC (rs6000-ibm-aix4.[12]*, 10706 powerpc-ibm-aix4.[12]*) 10707 + Tuning support for Itanium1 (Merced) variants. Note that code 10708 tuned for Itanium2 should also run correctly on Itanium1. 10709 * The protoize and unprotoize utilities have been obsoleted and will 10710 be removed in GCC 4.5. These utilities have not been installed by 10711 default since GCC 3.0. 10712 * Support has been removed for all the [2]configurations obsoleted in 10713 GCC 4.3. 10714 * Unknown -Wno-* options are now silently ignored by GCC if no other 10715 diagnostics are issued. If other diagnostics are issued, then GCC 10716 warns about the unknown options. 10717 * More information on porting to GCC 4.4 from previous versions of 10718 GCC can be found in the [3]porting guide for this release. 10719 10720 General Optimizer Improvements 10721 10722 * A new command-line switch -findirect-inlining has been added. When 10723 turned on it allows the inliner to also inline indirect calls that 10724 are discovered to have known targets at compile time thanks to 10725 previous inlining. 10726 * A new command-line switch -ftree-switch-conversion has been added. 10727 This new pass turns simple initializations of scalar variables in 10728 switch statements into initializations from a static array, given 10729 that all the values are known at compile time and the ratio between 10730 the new array size and the original switch branches does not exceed 10731 the parameter --param switch-conversion-max-branch-ratio (default 10732 is eight). 10733 * A new command-line switch -ftree-builtin-call-dce has been added. 10734 This optimization eliminates unnecessary calls to certain builtin 10735 functions when the return value is not used, in cases where the 10736 calls can not be eliminated entirely because the function may set 10737 errno. This optimization is on by default at -O2 and above. 10738 * A new command-line switch -fconserve-stack directs the compiler to 10739 minimize stack usage even if it makes the generated code slower. 10740 This affects inlining decisions. 10741 * When the assembler supports it, the compiler will now emit unwind 10742 information using assembler .cfi directives. This makes it possible 10743 to use such directives in inline assembler code. The new option 10744 -fno-dwarf2-cfi-asm directs the compiler to not use .cfi 10745 directives. 10746 * The [4]Graphite branch has been merged. This merge has brought in a 10747 new framework for loop optimizations based on a polyhedral 10748 intermediate representation. These optimizations apply to all the 10749 languages supported by GCC. The following new code transformations 10750 are available in GCC 4.4: 10751 + -floop-interchange performs loop interchange transformations 10752 on loops. Interchanging two nested loops switches the inner 10753 and outer loops. For example, given a loop like: 10754 DO J = 1, M 10755 DO I = 1, N 10756 A(J, I) = A(J, I) * C 10757 ENDDO 10758 ENDDO 10759 10760 loop interchange will transform the loop as if the user had 10761 written: 10762 DO I = 1, N 10763 DO J = 1, M 10764 A(J, I) = A(J, I) * C 10765 ENDDO 10766 ENDDO 10767 10768 which can be beneficial when N is larger than the caches, 10769 because in Fortran, the elements of an array are stored in 10770 memory contiguously by column, and the original loop iterates 10771 over rows, potentially creating at each access a cache miss. 10772 + -floop-strip-mine performs loop strip mining transformations 10773 on loops. Strip mining splits a loop into two nested loops. 10774 The outer loop has strides equal to the strip size and the 10775 inner loop has strides of the original loop within a strip. 10776 For example, given a loop like: 10777 DO I = 1, N 10778 A(I) = A(I) + C 10779 ENDDO 10780 10781 loop strip mining will transform the loop as if the user had 10782 written: 10783 DO II = 1, N, 4 10784 DO I = II, min (II + 3, N) 10785 A(I) = A(I) + C 10786 ENDDO 10787 ENDDO 10788 10789 + -floop-block performs loop blocking transformations on loops. 10790 Blocking strip mines each loop in the loop nest such that the 10791 memory accesses of the element loops fit inside caches. For 10792 example, given a loop like: 10793 DO I = 1, N 10794 DO J = 1, M 10795 A(J, I) = B(I) + C(J) 10796 ENDDO 10797 ENDDO 10798 10799 loop blocking will transform the loop as if the user had 10800 written: 10801 DO II = 1, N, 64 10802 DO JJ = 1, M, 64 10803 DO I = II, min (II + 63, N) 10804 DO J = JJ, min (JJ + 63, M) 10805 A(J, I) = B(I) + C(J) 10806 ENDDO 10807 ENDDO 10808 ENDDO 10809 ENDDO 10810 10811 which can be beneficial when M is larger than the caches, 10812 because the innermost loop will iterate over a smaller amount 10813 of data that can be kept in the caches. 10814 * A new register allocator has replaced the old one. It is called 10815 integrated register allocator (IRA) because coalescing, register 10816 live range splitting, and hard register preferencing are done 10817 on-the-fly during coloring. It also has better integration with the 10818 reload pass. IRA is a regional register allocator which uses modern 10819 Chaitin-Briggs coloring instead of Chow's priority coloring used in 10820 the old register allocator. More info about IRA internals and 10821 options can be found in the GCC manuals. 10822 * A new instruction scheduler and software pipeliner, based on the 10823 selective scheduling approach, has been added. The new pass 10824 performs instruction unification, register renaming, substitution 10825 through register copies, and speculation during scheduling. The 10826 software pipeliner is able to pipeline non-countable loops. The new 10827 pass is targeted at scheduling-eager in-order platforms. In GCC 4.4 10828 it is available for the Intel Itanium platform working by default 10829 as the second scheduling pass (after register allocation) at the 10830 -O3 optimization level. 10831 * When using -fprofile-generate with a multi-threaded program, the 10832 profile counts may be slightly wrong due to race conditions. The 10833 new -fprofile-correction option directs the compiler to apply 10834 heuristics to smooth out the inconsistencies. By default the 10835 compiler will give an error message when it finds an inconsistent 10836 profile. 10837 * The new -fprofile-dir=PATH option permits setting the directory 10838 where profile data files are stored when using -fprofile-generate 10839 and friends, and the directory used when reading profile data files 10840 using -fprofile-use and friends. 10841 10842 New warning options 10843 10844 * The new -Wframe-larger-than=NUMBER option directs GCC to emit a 10845 warning if any stack frame is larger than NUMBER bytes. This may be 10846 used to help ensure that code fits within a limited amount of stack 10847 space. 10848 * The command-line option -Wlarger-than-N is now written as 10849 -Wlarger-than=N and the old form is deprecated. 10850 * The new -Wno-mudflap option disables warnings about constructs 10851 which can not be instrumented when using -fmudflap. 10852 10853 New Languages and Language specific improvements 10854 10855 * Version 3.0 of the OpenMP specification is now supported for the C, 10856 C++, and Fortran compilers. 10857 * New character data types, per [5]TR 19769: New character types in 10858 C, are now supported for the C compiler in -std=gnu99 mode, as 10859 __CHAR16_TYPE__ and __CHAR32_TYPE__, and for the C++ compiler in 10860 -std=c++0x and -std=gnu++0x modes, as char16_t and char32_t too. 10861 10862 C family 10863 10864 * A new optimize attribute was added to allow programmers to change 10865 the optimization level and particular optimization options for an 10866 individual function. You can also change the optimization options 10867 via the GCC optimize pragma for functions defined after the pragma. 10868 The GCC push_options pragma and the GCC pop_options pragma allow 10869 you temporarily save and restore the options used. The GCC 10870 reset_options pragma restores the options to what was specified on 10871 the command line. 10872 * Uninitialized warnings do not require enabling optimization 10873 anymore, that is, -Wuninitialized can be used together with -O0. 10874 Nonetheless, the warnings given by -Wuninitialized will probably be 10875 more accurate if optimization is enabled. 10876 * -Wparentheses now warns about expressions such as (!x | y) and (!x 10877 & y). Using explicit parentheses, such as in ((!x) | y), silences 10878 this warning. 10879 * -Wsequence-point now warns within if, while,do while and for 10880 conditions, and within for begin/end expressions. 10881 * A new option -dU is available to dump definitions of preprocessor 10882 macros that are tested or expanded. 10883 10884 C++ 10885 10886 * [6]Improved experimental support for the upcoming ISO C++ standard, 10887 C++0x. Including support for auto, inline namespaces, generalized 10888 initializer lists, defaulted and deleted functions, new character 10889 types, and scoped enums. 10890 * Those errors that may be downgraded to warnings to build legacy 10891 code now mention -fpermissive when -fdiagnostics-show-option is 10892 enabled. 10893 * -Wconversion now warns if the result of a static_cast to enumeral 10894 type is unspecified because the value is outside the range of the 10895 enumeral type. 10896 * -Wuninitialized now warns if a non-static reference or non-static 10897 const member appears in a class without constructors. 10898 * G++ now properly implements value-initialization, so objects with 10899 an initializer of () and an implicitly defined default constructor 10900 will be zero-initialized before the default constructor is called. 10901 10902 Runtime Library (libstdc++) 10903 10904 * Improved experimental support for the upcoming ISO C++ standard, 10905 C++0x, including: 10906 + Support for <chrono>, <condition_variable>, <cstdatomic>, 10907 <forward_list>, <initializer_list>, <mutex>, <ratio>, 10908 <system_error>, and <thread>. 10909 + unique_ptr, <algorithm> additions, exception propagation, and 10910 support for the new character types in <string> and <limits>. 10911 + Existing facilities now exploit initializer lists, defaulted 10912 and deleted functions, and the newly implemented core C++0x 10913 features. 10914 + Some standard containers are more efficient together with 10915 stateful allocators, i.e., no allocator is constructed on the 10916 fly at element construction time. 10917 * Experimental support for non-standard pointer types in containers. 10918 * The long standing libstdc++/30928 has been fixed for targets 10919 running glibc 2.10 or later. 10920 * As usual, many small and larger bug fixes, in particular quite a 10921 few corner cases in <locale>. 10922 10923 Fortran 10924 10925 * GNU Fortran now employs libcpp directly instead of using cc1 as an 10926 external preprocessor. The [7]-cpp option was added to allow manual 10927 invocation of the preprocessor without relying on filename 10928 extensions. 10929 * The [8]-Warray-temporaries option warns about array temporaries 10930 generated by the compiler, as an aid to optimization. 10931 * The [9]-fcheck-array-temporaries option has been added, printing a 10932 notification at run time, when an array temporary had to be created 10933 for an function argument. Contrary to -Warray-temporaries the 10934 warning is only printed if the array is noncontiguous. 10935 * Improved generation of DWARF debugging symbols 10936 * If using an intrinsic not part of the selected standard (via -std= 10937 and -fall-intrinsics) gfortran will now treat it as if this 10938 procedure were declared EXTERNAL and try to link to a user-supplied 10939 procedure. -Wintrinsics-std will warn whenever this happens. The 10940 now-useless option -Wnonstd-intrinsic was removed. 10941 * The flag -falign-commons has been added to control the alignment of 10942 variables in COMMON blocks, which is enabled by default in line 10943 with previous GCC version. Using -fno-align-commons one can force 10944 commons to be contiguous in memory as required by the Fortran 10945 standard, however, this slows down the memory access. The option 10946 -Walign-commons, which is enabled by default, warns when padding 10947 bytes were added for alignment. The proper solution is to sort the 10948 common objects by decreasing storage size, which avoids the 10949 alignment problems. 10950 * Fortran 2003 support has been extended: 10951 + Wide characters (ISO 10646, UCS-4, kind=4) and UTF-8 I/O is 10952 now supported (except internal reads from/writes to wide 10953 strings). [10]-fbackslash now supports also \unnnn and 10954 \Unnnnnnnn to enter Unicode characters. 10955 + Asynchronous I/O (implemented as synchronous I/O) and the 10956 decimal=, size=, sign=, pad=, blank=, and delim= specifiers 10957 are now supported in I/O statements. 10958 + Support for Fortran 2003 structure constructors and for array 10959 constructor with typespec has been added. 10960 + Procedure Pointers (but not yet as component in derived types 10961 and as function results) are now supported. 10962 + Abstract types, type extension, and type-bound procedures 10963 (both PROCEDURE and GENERIC but not as operators). Note: As 10964 CLASS/polymorphyic types are not implemented, type-bound 10965 procedures with PASS accept as non-standard extension TYPE 10966 arguments. 10967 * Fortran 2008 support has been added: 10968 + The -std=f2008 option and support for the file extensions 10969 .f2008 and .F2008 has been added. 10970 + The g0 format descriptor is now supported. 10971 + The Fortran 2008 mathematical intrinsics ASINH, ACOSH, ATANH, 10972 ERF, ERFC, GAMMA, LOG_GAMMA, BESSEL_*, HYPOT, and ERFC_SCALED 10973 are now available (some of them existed as GNU extension 10974 before). Note: The hyperbolic functions are not yet supporting 10975 complex arguments and the three- argument version of BESSEL_*N 10976 is not available. 10977 + The bit intrinsics LEADZ and TRAILZ have been added. 10978 10979 Java (GCJ) 10980 10981 Ada 10982 10983 * The Ada runtime now supports multilibs on many platforms including 10984 x86_64, SPARC and PowerPC. Their build is enabled by default. 10985 10986 New Targets and Target Specific Improvements 10987 10988 ARM 10989 10990 * GCC now supports optimizing for the Cortex-A9, Cortex-R4 and 10991 Cortex-R4F processors and has many other improvements to 10992 optimization for ARM processors. 10993 * GCC now supports the VFPv3 variant with 16 double-precision 10994 registers with -mfpu=vfpv3-d16. The option -mfpu=vfp3 has been 10995 renamed to -mfpu=vfpv3. 10996 * GCC now supports the -mfix-cortex-m3-ldrd option to work around an 10997 erratum on Cortex-M3 processors. 10998 * GCC now supports the __sync_* atomic operations for ARM EABI 10999 GNU/Linux. 11000 * The section anchors optimization is now enabled by default when 11001 optimizing for ARM. 11002 * GCC now uses a new EABI-compatible profiling interface for EABI 11003 targets. This requires a function __gnu_mcount_nc, which is 11004 provided by GNU libc versions 2.8 and later. 11005 11006 AVR 11007 11008 * The -mno-tablejump option has been deprecated because it has the 11009 same effect as the -fno-jump-tables option. 11010 * Added support for these new AVR devices: 11011 + ATA6289 11012 + ATtiny13A 11013 + ATtiny87 11014 + ATtiny167 11015 + ATtiny327 11016 + ATmega8C1 11017 + ATmega16C1 11018 + ATmega32C1 11019 + ATmega8M1 11020 + ATmega16M1 11021 + ATmega32M1 11022 + ATmega32U4 11023 + ATmega16HVB 11024 + ATmega4HVD 11025 + ATmega8HVD 11026 + ATmega64C1 11027 + ATmega64M1 11028 + ATmega16U4 11029 + ATmega32U6 11030 + ATmega128RFA1 11031 + AT90PWM81 11032 + AT90SCR100 11033 + M3000F 11034 + M3000S 11035 + M3001B 11036 11037 IA-32/x86-64 11038 11039 * Support for Intel AES built-in functions and code generation is 11040 available via -maes. 11041 * Support for Intel PCLMUL built-in function and code generation is 11042 available via -mpclmul. 11043 * Support for Intel AVX built-in functions and code generation is 11044 available via -mavx. 11045 * Automatically align the stack for local variables with alignment 11046 requirement. 11047 * GCC can now utilize the SVML library for vectorizing calls to a set 11048 of C99 functions if -mveclibabi=svml is specified and you link to 11049 an SVML ABI compatible library. 11050 * On x86-64, the ABI has been changed in the following cases to 11051 conform to the x86-64 ABI: 11052 + Passing/returning structures with flexible array member: 11053 struct foo 11054 { 11055 int i; 11056 int flex[]; 11057 }; 11058 + Passing/returning structures with complex float member: 11059 struct foo 11060 { 11061 int i; 11062 __complex__ float f; 11063 }; 11064 + Passing/returning unions with long double member: 11065 union foo 11066 { 11067 int x; 11068 long double ld; 11069 }; 11070 Code built with previous versions of GCC that uses any of these is 11071 not compatible with code built with GCC 4.4.0 or later. 11072 * A new target attribute was added to allow programmers to change the 11073 target options like -msse2 or -march=k8 for an individual function. 11074 You can also change the target options via the GCC target pragma 11075 for functions defined after the pragma. 11076 * GCC can now be configured with options --with-arch-32, 11077 --with-arch-64, --with-cpu-32, --with-cpu-64, --with-tune-32 and 11078 --with-tune-64 to control the default optimization separately for 11079 32-bit and 64-bit modes. 11080 11081 IA-32/IA64 11082 11083 * Support for __float128 (TFmode) IEEE quad type and corresponding 11084 TCmode IEEE complex quad type is available via the soft-fp library 11085 on IA-32/IA64 targets. This includes basic arithmetic operations 11086 (addition, subtraction, negation, multiplication and division) on 11087 __float128 real and TCmode complex values, the full set of IEEE 11088 comparisons between __float128 values, conversions to and from 11089 float, double and long double floating point types, as well as 11090 conversions to and from signed or unsigned integer, signed or 11091 unsigned long integer and signed or unsigned quad (TImode, IA64 11092 only) integer types. Additionally, all operations generate the full 11093 set of IEEE exceptions and support the full set of IEEE rounding 11094 modes. 11095 11096 M68K/ColdFire 11097 11098 * GCC now supports instruction scheduling for ColdFire V1, V3 and V4 11099 processors. (Scheduling support for ColdFire V2 processors was 11100 added in GCC 4.3.) 11101 * GCC now supports the -mxgot option to support programs requiring 11102 many GOT entries on ColdFire. 11103 * The m68k-*-linux-gnu target now builds multilibs by default. 11104 11105 MIPS 11106 11107 * MIPS Technologies have extended the original MIPS SVR4 ABI to 11108 include support for procedure linkage tables (PLTs) and copy 11109 relocations. These extensions allow GNU/Linux executables to use a 11110 significantly more efficient code model than the one defined by the 11111 original ABI. 11112 GCC support for this code model is available via a new command-line 11113 option, -mplt. There is also a new configure-time option, 11114 --with-mips-plt, to make -mplt the default. 11115 The new code model requires support from the assembler, the linker, 11116 and the runtime C library. This support is available in binutils 11117 2.19 and GLIBC 2.9. 11118 * GCC can now generate MIPS16 code for 32-bit GNU/Linux executables 11119 and 32-bit GNU/Linux shared libraries. This feature requires GNU 11120 binutils 2.19 or above. 11121 * Support for RMI's XLR processor is now available through the 11122 -march=xlr and -mtune=xlr options. 11123 * 64-bit targets can now perform 128-bit multiplications inline, 11124 instead of relying on a libgcc function. 11125 * Native GNU/Linux toolchains now support -march=native and 11126 -mtune=native, which select the host processor. 11127 * GCC now supports the R10K, R12K, R14K and R16K processors. The 11128 canonical -march= and -mtune= names for these processors are 11129 r10000, r12000, r14000 and r16000 respectively. 11130 * GCC can now work around the side effects of speculative execution 11131 on R10K processors. Please see the documentation of the 11132 -mr10k-cache-barrier option for details. 11133 * Support for the MIPS64 Release 2 instruction set has been added. 11134 The option -march=mips64r2 enables generation of these 11135 instructions. 11136 * GCC now supports Cavium Networks' Octeon processor. This support is 11137 available through the -march=octeon and -mtune=octeon options. 11138 * GCC now supports STMicroelectronics' Loongson 2E/2F processors. The 11139 canonical -march= and -mtune= names for these processors are 11140 loongson2e and loongson2f. 11141 11142 picochip 11143 11144 Picochip is a 16-bit processor. A typical picoChip contains over 250 11145 small cores, each with small amounts of memory. There are three 11146 processor variants (STAN, MEM and CTRL) with different instruction sets 11147 and memory configurations and they can be chosen using the -mae option. 11148 11149 This port is intended to be a "C" only port. 11150 11151 Power Architecture and PowerPC 11152 11153 * GCC now supports the e300c2, e300c3 and e500mc processors. 11154 * GCC now supports Xilinx processors with a single-precision FPU. 11155 * Decimal floating point is now supported for e500 processors. 11156 11157 S/390, zSeries and System z9/z10 11158 11159 * Support for the IBM System z10 EC/BC processor has been added. When 11160 using the -march=z10 option, the compiler will generate code making 11161 use of instructions provided by the General-Instruction-Extension 11162 Facility and the Execute-Extension Facility. 11163 11164 VxWorks 11165 11166 * GCC now supports the thread-local storage mechanism used on 11167 VxWorks. 11168 11169 Xtensa 11170 11171 * GCC now supports thread-local storage (TLS) for Xtensa processor 11172 configurations that include the Thread Pointer option. TLS also 11173 requires support from the assembler and linker; this support is 11174 provided in the GNU binutils beginning with version 2.19. 11175 11176 Documentation improvements 11177 11178 Other significant improvements 11179 11180 GCC 4.4.1 11181 11182 This is the [11]list of problem reports (PRs) from GCC's bug tracking 11183 system that are known to be fixed in the 4.4.1 release. This list might 11184 not be complete (that is, it is possible that some PRs that have been 11185 fixed are not listed here). 11186 11187 GCC 4.4.2 11188 11189 This is the [12]list of problem reports (PRs) from GCC's bug tracking 11190 system that are known to be fixed in the 4.4.2 release. This list might 11191 not be complete (that is, it is possible that some PRs that have been 11192 fixed are not listed here). 11193 11194 GCC 4.4.3 11195 11196 This is the [13]list of problem reports (PRs) from GCC's bug tracking 11197 system that are known to be fixed in the 4.4.3 release. This list might 11198 not be complete (that is, it is possible that some PRs that have been 11199 fixed are not listed here). 11200 11201 GCC 4.4.4 11202 11203 This is the [14]list of problem reports (PRs) from GCC's bug tracking 11204 system that are known to be fixed in the 4.4.4 release. This list might 11205 not be complete (that is, it is possible that some PRs that have been 11206 fixed are not listed here). 11207 11208 GCC 4.4.5 11209 11210 This is the [15]list of problem reports (PRs) from GCC's bug tracking 11211 system that are known to be fixed in the 4.4.5 release. This list might 11212 not be complete (that is, it is possible that some PRs that have been 11213 fixed are not listed here). 11214 11215 GCC 4.4.6 11216 11217 This is the [16]list of problem reports (PRs) from GCC's bug tracking 11218 system that are known to be fixed in the 4.4.6 release. This list might 11219 not be complete (that is, it is possible that some PRs that have been 11220 fixed are not listed here). 11221 11222 GCC 4.4.7 11223 11224 This is the [17]list of problem reports (PRs) from GCC's bug tracking 11225 system that are known to be fixed in the 4.4.7 release. This list might 11226 not be complete (that is, it is possible that some PRs that have been 11227 fixed are not listed here). 11228 11229 11230 For questions related to the use of GCC, please consult these web 11231 pages and the [18]GCC manuals. If that fails, the 11232 [19]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 11233 web pages and the development of GCC are welcome on our developer 11234 list at [20]gcc (a] gcc.gnu.org. All of [21]our lists have public 11235 archives. 11236 11237 Copyright (C) [22]Free Software Foundation, Inc. Verbatim copying and 11238 distribution of this entire article is permitted in any medium, 11239 provided this notice is preserved. 11240 11241 These pages are [23]maintained by the GCC team. Last modified 11242 2022-11-01. 11243 11244 References 11245 11246 1. http://gcc.gnu.org/gcc-4.4/changes.html#4.4.7 11247 2. http://gcc.gnu.org/gcc-4.3/changes.html#obsoleted 11248 3. http://gcc.gnu.org/gcc-4.4/porting_to.html 11249 4. https://gcc.gnu.org/wiki/Graphite 11250 5. https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1040.pdf 11251 6. http://gcc.gnu.org/gcc-4.4/cxx0x_status.html 11252 7. https://gcc.gnu.org/onlinedocs/gfortran/Preprocessing-Options.html 11253 8. https://gcc.gnu.org/onlinedocs/gfortran/Error-and-Warning-Options.html#index-g_t_0040code_007bWarray-temporaries_007d-125 11254 9. https://gcc.gnu.org/onlinedocs/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfcheck-array-temporaries_007d-221 11255 10. https://gcc.gnu.org/onlinedocs/gfortran/Fortran-Dialect-Options.html#index-g_t_0040code_007bbackslash_007d-34 11256 11. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.1 11257 12. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.2 11258 13. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.3 11259 14. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.4 11260 15. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.5 11261 16. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.6 11262 17. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.4.7 11263 18. https://gcc.gnu.org/onlinedocs/ 11264 19. mailto:gcc-help (a] gcc.gnu.org 11265 20. mailto:gcc (a] gcc.gnu.org 11266 21. https://gcc.gnu.org/lists.html 11267 22. https://www.fsf.org/ 11268 23. https://gcc.gnu.org/about.html 11269 ====================================================================== 11270 http://gcc.gnu.org/gcc-4.3/index.html 11271 11272 GCC 4.3 Release Series 11273 11274 (This release series is no longer supported.) 11275 11276 Jun 27, 2011 11277 11278 The [1]GNU project and the GCC developers are pleased to announce the 11279 release of GCC 4.3.6. 11280 11281 This release is a bug-fix release, containing fixes for regressions in 11282 GCC 4.3.5 relative to previous releases of GCC. 11283 11284 Release History 11285 11286 GCC 4.3.6 11287 Jun 27, 2011 ([2]changes) 11288 11289 GCC 4.3.5 11290 May 22, 2010 ([3]changes) 11291 11292 GCC 4.3.4 11293 August 4, 2009 ([4]changes) 11294 11295 GCC 4.3.3 11296 January 24, 2009 ([5]changes) 11297 11298 GCC 4.3.2 11299 August 27, 2008 ([6]changes) 11300 11301 GCC 4.3.1 11302 June 6, 2008 ([7]changes) 11303 11304 GCC 4.3.0 11305 March 5, 2008 ([8]changes) 11306 11307 References and Acknowledgements 11308 11309 GCC used to stand for the GNU C Compiler, but since the compiler 11310 supports several other languages aside from C, it now stands for the 11311 GNU Compiler Collection. 11312 11313 A list of [9]successful builds is updated as new information becomes 11314 available. 11315 11316 The GCC developers would like to thank the numerous people that have 11317 contributed new features, improvements, bug fixes, and other changes as 11318 well as test results to GCC. This [10]amazing group of volunteers is 11319 what makes GCC successful. 11320 11321 For additional information about GCC please refer to the [11]GCC 11322 project web site or contact the [12]GCC development mailing list. 11323 11324 To obtain GCC please use [13]our mirror sites or [14]our version 11325 control system. 11326 11327 11328 For questions related to the use of GCC, please consult these web 11329 pages and the [15]GCC manuals. If that fails, the 11330 [16]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 11331 web pages and the development of GCC are welcome on our developer 11332 list at [17]gcc (a] gcc.gnu.org. All of [18]our lists have public 11333 archives. 11334 11335 Copyright (C) [19]Free Software Foundation, Inc. Verbatim copying and 11336 distribution of this entire article is permitted in any medium, 11337 provided this notice is preserved. 11338 11339 These pages are [20]maintained by the GCC team. Last modified 11340 2022-10-26. 11341 11342 References 11343 11344 1. http://www.gnu.org/ 11345 2. http://gcc.gnu.org/gcc-4.3/changes.html 11346 3. http://gcc.gnu.org/gcc-4.3/changes.html 11347 4. http://gcc.gnu.org/gcc-4.3/changes.html 11348 5. http://gcc.gnu.org/gcc-4.3/changes.html 11349 6. http://gcc.gnu.org/gcc-4.3/changes.html 11350 7. http://gcc.gnu.org/gcc-4.3/changes.html 11351 8. http://gcc.gnu.org/gcc-4.3/changes.html 11352 9. http://gcc.gnu.org/gcc-4.3/buildstat.html 11353 10. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 11354 11. http://gcc.gnu.org/index.html 11355 12. mailto:gcc (a] gcc.gnu.org 11356 13. http://gcc.gnu.org/mirrors.html 11357 14. http://gcc.gnu.org/git.html 11358 15. https://gcc.gnu.org/onlinedocs/ 11359 16. mailto:gcc-help (a] gcc.gnu.org 11360 17. mailto:gcc (a] gcc.gnu.org 11361 18. https://gcc.gnu.org/lists.html 11362 19. https://www.fsf.org/ 11363 20. https://gcc.gnu.org/about.html 11364 ====================================================================== 11365 http://gcc.gnu.org/gcc-4.3/changes.html 11366 11367 GCC 4.3 Release Series 11368 Changes, New Features, and Fixes 11369 11370 The latest release in the 4.3 release series is [1]GCC 4.3.5. 11371 11372 Caveats 11373 11374 * GCC requires the [2]GMP and [3]MPFR libraries for building all the 11375 various front-end languages it supports. See the [4]prerequisites 11376 page for version requirements. 11377 * ColdFire targets now treat long double as having the same format as 11378 double. In earlier versions of GCC, they used the 68881 long double 11379 format instead. 11380 * The m68k-uclinux target now uses the same calling conventions as 11381 m68k-linux-gnu. You can select the original calling conventions by 11382 configuring for m68k-uclinuxoldabi instead. Note that 11383 m68k-uclinuxoldabi also retains the original 80-bit long double on 11384 ColdFire targets. 11385 * The -fforce-mem option has been removed because it has had no 11386 effect in the last few GCC releases. 11387 * The i386 -msvr3-shlib option has been removed since it is no longer 11388 used. 11389 * Fastcall for i386 has been changed not to pass aggregate arguments 11390 in registers, following Microsoft compilers. 11391 * Support for the AOF assembler has been removed from the ARM back 11392 end; this affects only the targets arm-semi-aof and armel-semi-aof, 11393 which are no longer recognized. We removed these targets without a 11394 deprecation period because we discovered that they have been 11395 unusable since GCC 4.0.0. 11396 * Support for the TMS320C3x/C4x processor (targets c4x-* and tic4x-*) 11397 has been removed. This support had been deprecated since GCC 4.0.0. 11398 * Support for a number of older systems and recently unmaintained or 11399 untested target ports of GCC has been declared obsolete in GCC 4.3. 11400 Unless there is activity to revive them, the next release of GCC 11401 will have their sources permanently removed. 11402 All GCC ports for the following processor architectures have been 11403 declared obsolete: 11404 + Morpho MT (mt-*) 11405 The following aliases for processor architectures have been 11406 declared obsolete. Users should use the indicated generic target 11407 names instead, with compile-time options such as -mcpu or 11408 configure-time options such as --with-cpu to control the 11409 configuration more precisely. 11410 + strongarm*-*-*, ep9312*-*-*, xscale*-*-* (use arm*-*-* 11411 instead). 11412 + parisc*-*-* (use hppa*-*-* instead). 11413 + m680[012]0-*-* (use m68k-*-* instead). 11414 All GCC ports for the following operating systems have been 11415 declared obsolete: 11416 + BeOS (*-*-beos*) 11417 + kaOS (*-*-kaos*) 11418 + GNU/Linux using the a.out object format (*-*-linux*aout*) 11419 + GNU/Linux using version 1 of the GNU C Library 11420 (*-*-linux*libc1*) 11421 + Solaris versions before Solaris 7 (*-*-solaris2.[0-6], 11422 *-*-solaris2.[0-6].*) 11423 + Miscellaneous System V (*-*-sysv*) 11424 + WindISS (*-*-windiss*) 11425 Also, those for some individual systems on particular architectures 11426 have been obsoleted: 11427 + UNICOS/mk on DEC Alpha (alpha*-*-unicosmk*) 11428 + CRIS with a.out object format (cris-*-aout) 11429 + BSD 4.3 on PA-RISC (hppa1.1-*-bsd*) 11430 + OSF/1 on PA-RISC (hppa1.1-*-osf*) 11431 + PRO on PA-RISC (hppa1.1-*-pro*) 11432 + Sequent PTX on IA32 (i[34567]86-sequent-ptx4*, 11433 i[34567]86-sequent-sysv4*) 11434 + SCO Open Server 5 on IA32 (i[34567]86-*-sco3.2v5*) 11435 + UWIN on IA32 (i[34567]86-*-uwin*) (support for UWIN as a host 11436 was previously [5]removed in 2001, leaving only the support 11437 for UWIN as a target now being deprecated) 11438 + ChorusOS on PowerPC (powerpc-*-chorusos*) 11439 + All VAX configurations apart from NetBSD and OpenBSD 11440 (vax-*-bsd*, vax-*-sysv*, vax-*-ultrix*) 11441 * The [6]-Wconversion option has been modified. Its purpose now is to 11442 warn for implicit conversions that may alter a value. This new 11443 behavior is available for both C and C++. Warnings about 11444 conversions between signed and unsigned integers can be disabled by 11445 using -Wno-sign-conversion. In C++, they are disabled by default 11446 unless -Wsign-conversion is explicitly requested. The old behavior 11447 of -Wconversion, that is, warn for prototypes causing a type 11448 conversion that is different from what would happen to the same 11449 argument in the absence of a prototype, has been moved to a new 11450 option -Wtraditional-conversion, which is only available for C. 11451 * The -m386, -m486, -mpentium and -mpentiumpro tuning options have 11452 been removed because they were deprecated for more than 3 GCC major 11453 releases. Use -mtune=i386, -mtune=i486, -mtune=pentium or 11454 -mtune=pentiumpro as a replacement. 11455 * The -funsafe-math-optimizations option now automatically turns on 11456 -fno-trapping-math in addition to -fno-signed-zeros, as it enables 11457 reassociation and thus may introduce or remove traps. 11458 * The -ftree-vectorize option is now on by default under -O3. In 11459 order to generate code for a SIMD extension, it has to be enabled 11460 as well: use -maltivec for PowerPC platforms and -msse/-msse2 for 11461 i?86 and x86_64. 11462 * More information on porting to GCC 4.3 from previous versions of 11463 GCC can be found in the [7]porting guide for this release. 11464 11465 General Optimizer Improvements 11466 11467 * The GCC middle-end has been integrated with the MPFR library. This 11468 allows GCC to evaluate and replace at compile-time calls to 11469 built-in math functions having constant arguments with their 11470 mathematically equivalent results. In making use of MPFR, GCC can 11471 generate correct results regardless of the math library 11472 implementation or floating point precision of the host platform. 11473 This also allows GCC to generate identical results regardless of 11474 whether one compiles in native or cross-compile configurations to a 11475 particular target. The following built-in functions take advantage 11476 of this new capability: acos, acosh, asin, asinh, atan2, atan, 11477 atanh, cbrt, cos, cosh, drem, erf, erfc, exp10, exp2, exp, expm1, 11478 fdim, fma, fmax, fmin, gamma_r, hypot, j0, j1, jn, lgamma_r, log10, 11479 log1p, log2, log, pow10, pow, remainder, remquo, sin, sincos, sinh, 11480 tan, tanh, tgamma, y0, y1 and yn. The float and long double 11481 variants of these functions (e.g. sinf and sinl) are also handled. 11482 The sqrt and cabs functions with constant arguments were already 11483 optimized in prior GCC releases. Now they also use MPFR. 11484 * A new forward propagation pass on RTL was added. The new pass 11485 replaces several slower transformations, resulting in compile-time 11486 improvements as well as better code generation in some cases. 11487 * A new command-line switch -frecord-gcc-switches has been added to 11488 GCC, although it is only enabled for some targets. The switch 11489 causes the command line that was used to invoke the compiler to be 11490 recorded into the object file that is being created. The exact 11491 format of this recording is target and binary file format 11492 dependent, but it usually takes the form of a note section 11493 containing ASCII text. The switch is related to the -fverbose-asm 11494 switch, but that one only records the information in the assembler 11495 output file as comments, so the information never reaches the 11496 object file. 11497 * The inliner heuristic is now aware of stack frame consumption. New 11498 command-line parameters --param large-stack-frame and --param 11499 large-stack-frame-growth can be used to limit stack frame size 11500 growth caused by inlining. 11501 * During feedback directed optimizations, the expected block size the 11502 memcpy, memset and bzero functions operate on is discovered and for 11503 cases of commonly used small sizes, specialized inline code is 11504 generated. 11505 * __builtin_expect no longer requires its argument to be a compile 11506 time constant. 11507 * Interprocedural optimization was reorganized to work on functions 11508 in SSA form. This enables more precise and cheaper dataflow 11509 analysis and makes writing interprocedural optimizations easier. 11510 The following improvements have been implemented on top of this 11511 framework: 11512 + Pre-inline optimization: Selected local optimization passes 11513 are run before the inliner (and other interprocedural passes) 11514 are executed. This significantly improves the accuracy of code 11515 growth estimates used by the inliner and reduces the overall 11516 memory footprint for large compilation units. 11517 + Early inlining (a simple bottom-up inliner pass inlining only 11518 functions whose body is smaller than the expected call 11519 overhead) is now executed with the early optimization passes, 11520 thus inlining already optimized function bodies into an 11521 unoptimized function that is subsequently optimized by early 11522 optimizers. This enables the compiler to quickly eliminate 11523 abstraction penalty in C++ programs. 11524 + Interprocedural constant propagation now operate on SSA form 11525 increasing accuracy of the analysis. 11526 * A new internal representation for GIMPLE statements has been 11527 contributed, resulting in compile-time memory savings. 11528 * The vectorizer was enhanced to support vectorization of outer 11529 loops, intra-iteration parallelism (loop-aware SLP), vectorization 11530 of strided accesses and loops with multiple data-types. Run-time 11531 dependency testing using loop versioning was added. The cost model, 11532 turned on by -fvect-cost-model, was developed. 11533 11534 New Languages and Language specific improvements 11535 11536 * We have added new command-line options 11537 -finstrument-functions-exclude-function-list and 11538 -finstrument-functions-exclude-file-list. They provide more control 11539 over which functions are annotated by the -finstrument-functions 11540 option. 11541 11542 C family 11543 11544 * Implicit conversions between generic vector types are now only 11545 permitted when the two vectors in question have the same number of 11546 elements and compatible element types. (Note that the restriction 11547 involves compatible element types, not implicitly-convertible 11548 element types: thus, a vector type with element type int may not be 11549 implicitly converted to a vector type with element type unsigned 11550 int.) This restriction, which is in line with specifications for 11551 SIMD architectures such as AltiVec, may be relaxed using the flag 11552 -flax-vector-conversions. This flag is intended only as a 11553 compatibility measure and should not be used for new code. 11554 * -Warray-bounds has been added and is now enabled by default for 11555 -Wall . It produces warnings for array subscripts that can be 11556 determined at compile time to be always out of bounds. 11557 -Wno-array-bounds will disable the warning. 11558 * The constructor and destructor function attributes now accept 11559 optional priority arguments which control the order in which the 11560 constructor and destructor functions are run. 11561 * New [8]command-line options -Wtype-limits, -Wold-style-declaration, 11562 -Wmissing-parameter-type, -Wempty-body, -Wclobbered and 11563 -Wignored-qualifiers have been added for finer control of the 11564 diverse warnings enabled by -Wextra. 11565 * A new function attribute alloc_size has been added to mark up 11566 malloc style functions. For constant sized allocations this can be 11567 used to find out the size of the returned pointer using the 11568 __builtin_object_size() function for buffer overflow checking and 11569 similar. This supplements the already built-in malloc and calloc 11570 constant size handling. 11571 * Integer constants written in binary are now supported as a GCC 11572 extension. They consist of a prefix 0b or 0B, followed by a 11573 sequence of 0 and 1 digits. 11574 * A new predefined macro __COUNTER__ has been added. It expands to 11575 sequential integral values starting from 0. In conjunction with the 11576 ## operator, this provides a convenient means to generate unique 11577 identifiers. 11578 * A new command-line option -fdirectives-only has been added. It 11579 enables a special preprocessing mode which improves the performance 11580 of applications like distcc and ccache. 11581 * Fixed-point data types and operators have been added. They are 11582 based on Chapter 4 of the Embedded-C specification (n1169.pdf). 11583 Currently, only MIPS targets are supported. 11584 * Decimal floating-point arithmetic based on draft ISO/IEC TR 24732, 11585 N1241, is now supported as a GCC extension to C for targets 11586 i[34567]86-*-linux-gnu, powerpc*-*-linux-gnu, s390*-ibm-linux-gnu, 11587 and x86_64-*-linux-gnu. The feature introduces new data types 11588 _Decimal32, _Decimal64, and _Decimal128 with constant suffixes DF, 11589 DD, and DL. 11590 11591 C++ 11592 11593 * [9]Experimental support for the upcoming ISO C++ standard, C++0x. 11594 * -Wc++0x-compat has been added and is now enabled by default for 11595 -Wall. It produces warnings for constructs whose meaning differs 11596 between ISO C++ 1998 and C++0x. 11597 * The -Wparentheses option now works for C++ as it does for C. It 11598 warns if parentheses are omitted when operators with confusing 11599 precedence are nested. It also warns about ambiguous else 11600 statements. Since -Wparentheses is enabled by -Wall, this may cause 11601 additional warnings with existing C++ code which uses -Wall. These 11602 new warnings may be disabled by using -Wall -Wno-parentheses. 11603 * The -Wmissing-declarations now works for C++ as it does for C. 11604 * The -fvisibility-ms-compat flag was added, to make it easier to 11605 port larger projects using shared libraries from Microsoft's Visual 11606 Studio to ELF and Mach-O systems. 11607 * C++ attribute handling has been overhauled for template arguments 11608 (ie dependent types). In particular, __attribute__((aligned(T))); 11609 works for C++ types. 11610 11611 Runtime Library (libstdc++) 11612 11613 * [10]Experimental support for the upcoming ISO C++ standard, C++0x. 11614 * Support for TR1 mathematical special functions and regular 11615 expressions. 11616 * Default what implementations give more elaborate exception strings 11617 for bad_cast, bad_typeid, bad_exception, and bad_alloc. 11618 * Header dependencies have been streamlined, reducing unnecessary 11619 includes and pre-processed bloat. 11620 * Variadic template implementations of items in <tuple> and 11621 <functional>. 11622 * An experimental [11]parallel mode has been added. This is a 11623 parallel implementation of many C++ Standard library algorithms, 11624 like std::accumulate, std::for_each, std::transform, or std::sort, 11625 to give but four examples. These algorithms can be substituted for 11626 the normal (sequential) libstdc++ algorithms on a piecemeal basis, 11627 or all existing algorithms can be transformed via the 11628 -D_GLIBCXX_PARALLEL macro. 11629 * Debug mode versions of classes in <unordered_set> and 11630 <unordered_map>. 11631 * Formal deprecation of <ext/hash_set> and <ext/hash_map>, which are 11632 now <backward/hash_set> and <backward/hash_map>. This code: 11633 #include <ext/hash_set> 11634 __gnu_cxx::hash_set<int> s; 11635 11636 Can be transformed (in order of preference) to: 11637 #include <tr1/unordered_set> 11638 std::tr1::unordered_set<int> s; 11639 11640 or 11641 #include <backward/hash_set> 11642 __gnu_cxx::hash_set<int> s; 11643 11644 Similar transformations apply to __gnu_cxx::hash_map, 11645 __gnu_cxx::hash_multimap, __gnu_cxx::hash_set, 11646 __gnu_cxx::hash_multiset. 11647 11648 Fortran 11649 11650 * Due to the fact that the GMP and MPFR libraries are required for 11651 all languages, Fortran is no longer special in this regard and is 11652 available by default. 11653 * The [12]-fexternal-blas option has been added, which generates 11654 calls to BLAS routines for intrinsic matrix operations such as 11655 matmul rather than using the built-in algorithms. 11656 * Support to give a backtrace (compiler flag -fbacktrace or 11657 environment variable GFORTRAN_ERROR_BACKTRACE; on glibc systems 11658 only) or a core dump (-fdump-core, GFORTRAN_ERROR_DUMPCORE) when a 11659 run-time error occured. 11660 * GNU Fortran now defines __GFORTRAN__ when it runs the C 11661 preprocessor (CPP). 11662 * The [13]-finit-local-zero, -finit-real, -finit-integer, 11663 -finit-character, and -finit-logical options have been added, which 11664 can be used to initialize local variables. 11665 * The intrinsic procedures [14]GAMMA and [15]LGAMMA have been added, 11666 which calculate the Gamma function and its logarithm. Use EXTERNAL 11667 gamma if you want to use your own gamma function. 11668 * GNU Fortran now regards the backslash character as literal (as 11669 required by the Fortran 2003 standard); using [16]-fbackslash GNU 11670 Fortran interprets backslashes as C-style escape characters. 11671 * The [17]interpretation of binary, octal and hexadecimal (BOZ) 11672 literal constants has been changed. Before they were always 11673 interpreted as integer; now they are bit-wise transferred as 11674 argument of INT, REAL, DBLE and CMPLX as required by the Fortran 11675 2003 standard, and for real and complex variables in DATA 11676 statements or when directly assigned to real and complex variables. 11677 Everywhere else and especially in expressions they are still 11678 regarded as integer constants. 11679 * Fortran 2003 support has been extended: 11680 + Intrinsic statements IMPORT, PROTECTED, VALUE and VOLATILE 11681 + Pointer intent 11682 + Intrinsic module ISO_ENV_FORTRAN 11683 + Interoperability with C (ISO C Bindings) 11684 + ABSTRACT INTERFACES and PROCEDURE statements (without POINTER 11685 attribute) 11686 + Fortran 2003 BOZ 11687 11688 Java (GCJ) 11689 11690 * GCJ now uses the Eclipse Java compiler for its Java parsing needs. 11691 This enables the use of all 1.5 language features, and fixes most 11692 existing front end bugs. 11693 * libgcj now supports all 1.5 language features which require runtime 11694 support: foreach, enum, annotations, generics, and auto-boxing. 11695 * We've made many changes to the tools shipped with gcj. 11696 + The old jv-scan tool has been removed. This tool never really 11697 worked properly. There is no replacement. 11698 + gcjh has been rewritten. Some of its more obscure options no 11699 longer work, but are still recognized in an attempt at 11700 compatibility. gjavah is a new program with similar 11701 functionality but different command-line options. 11702 + grmic and grmiregistry have been rewritten. grmid has been 11703 added. 11704 + gjar replaces the old fastjar. 11705 + gjarsigner (used for signing jars), gkeytool (used for key 11706 management), gorbd (for CORBA), gserialver (computes 11707 serialization UIDs), and gtnameserv (also for CORBA) are now 11708 installed. 11709 * The ability to dump the contents of the java run time heap to a 11710 file for off-line analysis has been added. The heap dumps may be 11711 analyzed with the new gc-analyze tool. They may be generated on 11712 out-of-memory conditions or on demand and are controlled by the new 11713 run time class gnu.gcj.util.GCInfo. 11714 * java.util.TimeZone can now read files from /usr/share/zoneinfo to 11715 provide correct, updated, timezone information. This means that 11716 packagers no longer have to update libgcj when a time zone change 11717 is published. 11718 11719 New Targets and Target Specific Improvements 11720 11721 IA-32/x86-64 11722 11723 * Tuning for Intel Core 2 processors is available via -mtune=core2 11724 and -march=core2. 11725 * Tuning for AMD Geode processors is available via -mtune=geode and 11726 -march=geode. 11727 * Code generation of block move (memcpy) and block set (memset) was 11728 rewritten. GCC can now pick the best algorithm (loop, unrolled 11729 loop, instruction with rep prefix or a library call) based on the 11730 size of the block being copied and the CPU being optimized for. A 11731 new option -minline-stringops-dynamically has been added. With this 11732 option string operations of unknown size are expanded such that 11733 small blocks are copied by in-line code, while for large blocks a 11734 library call is used. This results in faster code than 11735 -minline-all-stringops when the library implementation is capable 11736 of using cache hierarchy hints. The heuristic choosing the 11737 particular algorithm can be overwritten via -mstringop-strategy. 11738 Newly also memset of values different from 0 is inlined. 11739 * GCC no longer places the cld instruction before string operations. 11740 Both i386 and x86-64 ABI documents mandate the direction flag to be 11741 clear at the entry of a function. It is now invalid to set the flag 11742 in asm statement without reseting it afterward. 11743 * Support for SSSE3 built-in functions and code generation are 11744 available via -mssse3. 11745 * Support for SSE4.1 built-in functions and code generation are 11746 available via -msse4.1. 11747 * Support for SSE4.2 built-in functions and code generation are 11748 available via -msse4.2. 11749 * Both SSE4.1 and SSE4.2 support can be enabled via -msse4. 11750 * A new set of options -mpc32, -mpc64 and -mpc80 have been added to 11751 allow explicit control of x87 floating point precision. 11752 * Support for __float128 (TFmode) IEEE quad type and corresponding 11753 TCmode IEEE complex quad type is available via the soft-fp library 11754 on x86_64 targets. This includes basic arithmetic operations 11755 (addition, subtraction, negation, multiplication and division) on 11756 __float128 real and TCmode complex values, the full set of IEEE 11757 comparisons between __float128 values, conversions to and from 11758 float, double and long double floating point types, as well as 11759 conversions to and from signed or unsigned integer, signed or 11760 unsigned long integer and signed or unsigned quad (TImode) integer 11761 types. Additionally, all operations generate the full set of IEEE 11762 exceptions and support the full set of IEEE rounding modes. 11763 * GCC can now utilize the ACML library for vectorizing calls to a set 11764 of C99 functions on x86_64 if -mveclibabi=acml is specified and you 11765 link to an ACML ABI compatible library. 11766 11767 ARM 11768 11769 * Compiler and Library support for Thumb-2 and the ARMv7 architecture 11770 has been added. 11771 11772 CRIS 11773 11774 New features 11775 11776 * Compiler and Library support for the CRIS v32 architecture, as 11777 found in Axis Communications ETRAX FS and ARTPEC-3 chips, has been 11778 added. 11779 11780 Configuration changes 11781 11782 * The cris-*-elf target now includes support for CRIS v32, including 11783 libraries, through the -march=v32 option. 11784 * A new crisv32-*-elf target defaults to generate code for CRIS v32. 11785 * A new crisv32-*-linux* target defaults to generate code for CRIS 11786 v32. 11787 * The cris-*-aout target has been obsoleted. 11788 11789 Improved support for built-in functions 11790 11791 * GCC can now use the lz and swapwbr instructions to implement the 11792 __builtin_clz, __builtin_ctz and __builtin_ffs family of functions. 11793 * __builtin_bswap32 is now implemented using the swapwb instruction, 11794 when available. 11795 11796 m68k and ColdFire 11797 11798 New features 11799 11800 * Support for several new ColdFire processors has been added. You can 11801 generate code for them using the new -mcpu option. 11802 * All targets now support ColdFire processors. 11803 * m68k-uclinux targets have improved support for C++ constructors and 11804 destructors, and for shared libraries. 11805 * It is now possible to set breakpoints on the first or last line of 11806 a function, even if there are no statements on that line. 11807 11808 Optimizations 11809 11810 * Support for sibling calls has been added. 11811 * More use is now made of the ColdFire mov3q instruction. 11812 * __builtin_clz is now implemented using the ff1 ColdFire 11813 instruction, when available. 11814 * GCC now honors the -m68010 option. 68010 code now uses clr rather 11815 than move to zero volatile memory. 11816 * 68020 targets and above can now use symbol(index.size*scale) 11817 addresses for indexed array accesses. Earlier compilers would 11818 always load the symbol into a base register first. 11819 11820 Configuration changes 11821 11822 * All m68k and ColdFire targets now allow the default processor to be 11823 set at configure time using --with-cpu. 11824 * A --with-arch configuration option has been added. This option 11825 allows you to restrict a target to ColdFire or non-ColdFire 11826 processors. 11827 11828 Preprocessor macros 11829 11830 * An __mcfv*__ macro is now defined for all ColdFire targets. 11831 (Earlier versions of GCC only defined __mcfv4e__.) 11832 * __mcf_cpu_*, __mcf_family_* and __mcffpu__ macros have been added. 11833 * All targets now define __mc68010 and __mc68010__ when generating 11834 68010 code. 11835 11836 Command-line changes 11837 11838 * New command-line options -march, -mcpu, -mtune and -mhard-float 11839 have been added. These options apply to both m68k and ColdFire 11840 targets. 11841 * -mno-short, -mno-bitfield and -mno-rtd are now accepted as negative 11842 versions of -mshort, etc. 11843 * -fforce-addr has been removed. It is now ignored by the compiler. 11844 11845 Other improvements 11846 11847 * ColdFire targets now try to maintain a 4-byte-aligned stack where 11848 possible. 11849 * m68k-uclinux targets now try to avoid situations that lead to the 11850 load-time error: BINFMT_FLAT: reloc outside program. 11851 11852 MIPS 11853 11854 Changes to existing configurations 11855 11856 * libffi and libjava now support all three GNU/Linux ABIs: o32, n32 11857 and n64. Every GNU/Linux configuration now builds these libraries 11858 by default. 11859 * GNU/Linux configurations now generate -mno-shared code unless 11860 overridden by -fpic, -fPIC, -fpie or -fPIE. 11861 * mipsisa32*-linux-gnu configurations now generate hard-float code by 11862 default, just like other mipsisa32* and mips*-linux-gnu 11863 configurations. You can build a soft-float version of any 11864 mips*-linux-gnu configuration by passing --with-float=soft to 11865 configure. 11866 * mips-wrs-vxworks now supports run-time processes (RTPs). 11867 11868 Changes to existing command-line options 11869 11870 * The -march and -mtune options no longer accept 24k as a processor 11871 name. Please use 24kc, 24kf2_1 or 24kf1_1 instead. 11872 * The -march and -mtune options now accept 24kf2_1, 24kef2_1 and 11873 34kf2_1 as synonyms for 24kf, 24kef and 34kf respectively. The 11874 options also accept 24kf1_1, 24kef1_1 and 34kf1_1 as synonyms for 11875 24kx, 24kex and 34kx. 11876 11877 New configurations 11878 11879 GCC now supports the following configurations: 11880 * mipsisa32r2*-linux-gnu*, which generates MIPS32 revision 2 code by 11881 default. Earlier releases also recognized this configuration, but 11882 they treated it in the same way as mipsisa32*-linux-gnu*. Note that 11883 you can customize any mips*-linux-gnu* configuration to a 11884 particular ISA or processor by passing an appropriate --with-arch 11885 option to configure. 11886 * mipsisa*-sde-elf*, which provides compatibility with MIPS 11887 Technologies' SDE toolchains. The configuration uses the SDE 11888 libraries by default, but you can use it like other newlib-based 11889 ELF configurations by passing --with-newlib to configure. It is the 11890 only configuration besides mips64vr*-elf* to build MIPS16 as well 11891 as non-MIPS16 libraries. 11892 * mipsisa*-elfoabi*, which is similar to the general mipsisa*-elf* 11893 configuration, but uses the o32 and o64 ABIs instead of the 32-bit 11894 and 64-bit forms of the EABI. 11895 11896 New processors and application-specific extensions 11897 11898 * Support for the SmartMIPS ASE is available through the new 11899 -msmartmips option. 11900 * Support for revision 2 of the DSP ASE is available through the new 11901 -mdspr2 option. A new preprocessor macro called __mips_dsp_rev 11902 indicates the revision of the ASE in use. 11903 * Support for the 4KS and 74K families of processors is available 11904 through the -march and -mtune options. 11905 11906 Improved support for built-in functions 11907 11908 * GCC can now use load-linked, store-conditional and sync 11909 instructions to implement atomic built-in functions such as 11910 __sync_fetch_and_add. The memory reference must be 4 bytes wide for 11911 32-bit targets and either 4 or 8 bytes wide for 64-bit targets. 11912 * GCC can now use the clz and dclz instructions to implement the 11913 __builtin_ctz and __builtin_ffs families of functions. 11914 * There is a new __builtin___clear_cache function for flushing the 11915 instruction cache. GCC expands this function inline on MIPS32 11916 revision 2 targets, otherwise it calls the function specified by 11917 -mcache-flush-func. 11918 11919 MIPS16 improvements 11920 11921 * GCC can now compile objects that contain a mixture of MIPS16 and 11922 non-MIPS16 code. There are two new attributes, mips16 and nomips16, 11923 for specifying which mode a function should use. 11924 * A new option called -minterlink-mips16 makes non-MIPS16 code 11925 link-compatible with MIPS16 code. 11926 * After many bug fixes, the long-standing MIPS16 -mhard-float support 11927 should now work fairly reliably. 11928 * GCC can now use the MIPS16e save and restore instructions. 11929 * -fsection-anchors now works in MIPS16 mode. MIPS16 code compiled 11930 with -G0 -fsection-anchors is often smaller than code compiled with 11931 -G8. However, please note that you must usually compile all objects 11932 in your application with the same -G option; see the documentation 11933 of -G for details. 11934 * A new option called-mcode-readable specifies which instructions are 11935 allowed to load from the code segment. -mcode-readable=yes is the 11936 default and says that any instruction may load from the code 11937 segment. The other alternatives are -mcode-readable=pcrel, which 11938 says that only PC-relative MIPS16 instructions may load from the 11939 code segment, and -mcode-readable=no, which says that no 11940 instruction may do so. Please see the documentation for more 11941 details, including example uses. 11942 11943 Small-data improvements 11944 11945 There are three new options for controlling small data: 11946 * -mno-extern-sdata, which disables small-data accesses for 11947 externally-defined variables. Code compiled with -Gn 11948 -mno-extern-sdata will be link-compatible with any -G setting 11949 between -G0 and -Gn inclusive. 11950 * -mno-local-sdata, which disables the use of small-data sections for 11951 data that is not externally visible. This option can be a useful 11952 way of reducing small-data usage in less performance-critical parts 11953 of an application. 11954 * -mno-gpopt, which disables the use of the $gp register while still 11955 honoring the -G limit when placing externally-visible data. This 11956 option implies -mno-extern-sdata and -mno-local-sdata and it can be 11957 useful in situations where $gp does not necessarily hold the 11958 expected value. 11959 11960 Miscellaneous improvements 11961 11962 * There is a new option called -mbranch-cost for tweaking the 11963 perceived cost of branches. 11964 * If GCC is configured to use a version of GAS that supports the 11965 .gnu_attribute directive, it will use that directive to record 11966 certain properties of the output code. .gnu_attribute is new to GAS 11967 2.18. 11968 * There are two new function attributes, near and far, for overriding 11969 the command-line setting of -mlong-calls on a function-by-function 11970 basis. 11971 * -mfp64, which previously required a 64-bit target, now works with 11972 MIPS32 revision 2 targets as well. The mipsisa*-elfoabi* and 11973 mipsisa*-sde-elf* configurations provide suitable library support. 11974 * GCC now recognizes the -mdmx and -mmt options and passes them down 11975 to the assembler. It does nothing else with the options at present. 11976 11977 SPU (Synergistic Processor Unit) of the Cell Broadband Engine Architecture 11978 (BEA) 11979 11980 * Support has been added for this new architecture. 11981 11982 RS6000 (POWER/PowerPC) 11983 11984 * Support for the PowerPC 750CL paired-single instructions has been 11985 added with a new powerpc-*-linux*paired* target configuration. It 11986 is enabled by an associated -mpaired option and can be accessed 11987 using new built-in functions. 11988 * Support for auto-detecting architecture and system configuration to 11989 auto-select processor optimization tuning. 11990 * Support for VMX on AIX 5.3 has been added. 11991 * Support for AIX Version 6.1 has been added. 11992 11993 S/390, zSeries and System z9 11994 11995 * Support for the IBM System z9 EC/BC processor (z9 GA3) has been 11996 added. When using the -march=z9-ec option, the compiler will 11997 generate code making use of instructions provided by the decimal 11998 floating point facility and the floating point conversion facility 11999 (pfpo). Besides the instructions used to implement decimal floating 12000 point operations these facilities also contain instructions to move 12001 between general purpose and floating point registers and to modify 12002 and copy the sign-bit of floating point values. 12003 * When the -march=z9-ec option is used the new 12004 -mhard-dfp/-mno-hard-dfp options can be used to specify whether the 12005 decimal floating point hardware instructions will be used or not. 12006 If none of them is given the hardware support is enabled by 12007 default. 12008 * The -mstack-guard option can now be omitted when using stack 12009 checking via -mstack-size in order to let GCC choose a sensible 12010 stack guard value according to the frame size of each function. 12011 * Various changes to improve performance of generated code have been 12012 implemented, including: 12013 + The condition code set by an add logical with carry 12014 instruction is now available for overflow checks like: a + b + 12015 carry < b. 12016 + The test data class instruction is now used to implement 12017 sign-bit and infinity checks of binary and decimal floating 12018 point numbers. 12019 12020 SPARC 12021 12022 * Support for the Sun UltraSPARC T2 (Niagara 2) processor has been 12023 added. 12024 12025 Xtensa 12026 12027 * Stack unwinding for exception handling now uses by default a 12028 specialized version of DWARF unwinding. This is not 12029 binary-compatible with the setjmp/longjmp (sjlj) unwinding used for 12030 Xtensa with previous versions of GCC. 12031 * For Xtensa processors that include the Conditional Store option, 12032 the built-in functions for atomic memory access are now implemented 12033 using S32C1I instructions. 12034 * If the Xtensa NSA option is available, GCC will use it to implement 12035 the __builtin_ctz and __builtin_clz functions. 12036 12037 Documentation improvements 12038 12039 * Existing libstdc++ documentation has been edited and restructured 12040 into a single DocBook XML manual. The results can be viewed online 12041 [18]here. 12042 12043 Other significant improvements 12044 12045 * The compiler's --help command-line option has been extended so that 12046 it now takes an optional set of arguments. These arguments restrict 12047 the information displayed to specific classes of command-line 12048 options, and possibly only a subset of those options. It is also 12049 now possible to replace the descriptive text associated with each 12050 displayed option with an indication of its current value, or for 12051 binary options, whether it has been enabled or disabled. 12052 Here are some examples. The following will display all the options 12053 controlling warning messages: 12054 --help=warnings 12055 12056 Whereas this will display all the undocumented, target specific 12057 options: 12058 --help=target,undocumented 12059 12060 This sequence of commands will display the binary optimizations 12061 that are enabled by -O3: 12062 gcc -c -Q -O3 --help=optimizers > /tmp/O3-opts 12063 gcc -c -Q -O2 --help=optimizers > /tmp/O2-opts 12064 diff /tmp/O2-opts /tmp/O3-opts | grep enabled 12065 12066 * The configure options --with-pkgversion and --with-bugurl have been 12067 added. These allow distributors of GCC to include a 12068 distributor-specific string in manuals and --version output and to 12069 specify the URL for reporting bugs in their versions of GCC. 12070 12071 GCC 4.3.1 12072 12073 This is the [19]list of problem reports (PRs) from GCC's bug tracking 12074 system that are known to be fixed in the 4.3.1 release. This list might 12075 not be complete (that is, it is possible that some PRs that have been 12076 fixed are not listed here). 12077 12078 Target Specific Changes 12079 12080 IA-32/x86-64 12081 12082 ABI changes 12083 12084 * Starting with GCC 4.3.1, decimal floating point variables are 12085 aligned to their natural boundaries when they are passed on the 12086 stack for i386. 12087 12088 Command-line changes 12089 12090 * Starting with GCC 4.3.1, the -mcld option has been added to 12091 automatically generate a cld instruction in the prologue of 12092 functions that use string instructions. This option is used for 12093 backward compatibility on some operating systems and can be enabled 12094 by default for 32-bit x86 targets by configuring GCC with the 12095 --enable-cld configure option. 12096 12097 GCC 4.3.2 12098 12099 This is the [20]list of problem reports (PRs) from GCC's bug tracking 12100 system that are known to be fixed in the 4.3.2 release. This list might 12101 not be complete (that is, it is possible that some PRs that have been 12102 fixed are not listed here). 12103 12104 GCC 4.3.3 12105 12106 This is the [21]list of problem reports (PRs) from GCC's bug tracking 12107 system that are known to be fixed in the 4.3.3 release. This list might 12108 not be complete (that is, it is possible that some PRs that have been 12109 fixed are not listed here). 12110 12111 GCC 4.3.4 12112 12113 This is the [22]list of problem reports (PRs) from GCC's bug tracking 12114 system that are known to be fixed in the 4.3.4 release. This list might 12115 not be complete (that is, it is possible that some PRs that have been 12116 fixed are not listed here). 12117 12118 GCC 4.3.5 12119 12120 This is the [23]list of problem reports (PRs) from GCC's bug tracking 12121 system that are known to be fixed in the 4.3.5 release. This list might 12122 not be complete (that is, it is possible that some PRs that have been 12123 fixed are not listed here). 12124 12125 GCC 4.3.6 12126 12127 This is the [24]list of problem reports (PRs) from GCC's bug tracking 12128 system that are known to be fixed in the 4.3.6 release. This list might 12129 not be complete (that is, it is possible that some PRs that have been 12130 fixed are not listed here). 12131 12132 12133 For questions related to the use of GCC, please consult these web 12134 pages and the [25]GCC manuals. If that fails, the 12135 [26]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 12136 web pages and the development of GCC are welcome on our developer 12137 list at [27]gcc (a] gcc.gnu.org. All of [28]our lists have public 12138 archives. 12139 12140 Copyright (C) [29]Free Software Foundation, Inc. Verbatim copying and 12141 distribution of this entire article is permitted in any medium, 12142 provided this notice is preserved. 12143 12144 These pages are [30]maintained by the GCC team. Last modified 12145 2022-10-26. 12146 12147 References 12148 12149 1. http://gcc.gnu.org/gcc-4.3/changes.html#4.3.5 12150 2. https://gmplib.org/ 12151 3. https://www.mpfr.org/ 12152 4. https://gcc.gnu.org/install/prerequisites.html 12153 5. https://gcc.gnu.org/ml/gcc-announce/2001/msg00000.html 12154 6. https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#Warning-Options 12155 7. http://gcc.gnu.org/gcc-4.3/porting_to.html 12156 8. https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html 12157 9. http://gcc.gnu.org/gcc-4.3/cxx0x_status.html 12158 10. http://gcc.gnu.org/gcc-4.3/cxx0x_status.html 12159 11. https://gcc.gnu.org/onlinedocs/libstdc++/manual/parallel_mode.html 12160 12. https://gcc.gnu.org/onlinedocs/gfortran/Code-Gen-Options.html#Code-Gen-Options 12161 13. https://gcc.gnu.org/onlinedocs/gfortran/Code-Gen-Options.html#index-g_t_0040code_007bfinit-local-zero_007d-167 12162 14. https://gcc.gnu.org/onlinedocs/gcc-4.3.0/gfortran/GAMMA.html 12163 15. https://gcc.gnu.org/onlinedocs/gcc-4.3.0/gfortran/LGAMMA.html 12164 16. https://gcc.gnu.org/onlinedocs/gfortran/Fortran-Dialect-Options.html 12165 17. https://gcc.gnu.org/onlinedocs/gfortran/BOZ-literal-constants.html 12166 18. https://gcc.gnu.org/onlinedocs/libstdc++/ 12167 19. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.3.1 12168 20. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.3.2 12169 21. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.3.3 12170 22. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.3.4 12171 23. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.3.5 12172 24. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.3.6 12173 25. https://gcc.gnu.org/onlinedocs/ 12174 26. mailto:gcc-help (a] gcc.gnu.org 12175 27. mailto:gcc (a] gcc.gnu.org 12176 28. https://gcc.gnu.org/lists.html 12177 29. https://www.fsf.org/ 12178 30. https://gcc.gnu.org/about.html 12179 ====================================================================== 12180 http://gcc.gnu.org/gcc-4.2/index.html 12181 12182 GCC 4.2 Release Series 12183 12184 (This release series is no longer supported.) 12185 12186 May 19, 2008 12187 12188 The [1]GNU project and the GCC developers are pleased to announce the 12189 release of GCC 4.2.4. 12190 12191 This release is a bug-fix release, containing fixes for regressions in 12192 GCC 4.2.3 relative to previous releases of GCC. 12193 12194 Release History 12195 12196 GCC 4.2.4 12197 May 19, 2008 ([2]changes) 12198 12199 GCC 4.2.3 12200 February 1, 2008 ([3]changes) 12201 12202 GCC 4.2.2 12203 October 7, 2007 ([4]changes) 12204 12205 GCC 4.2.1 12206 July 18, 2007 ([5]changes) 12207 12208 GCC 4.2.0 12209 May 13, 2007 ([6]changes) 12210 12211 References and Acknowledgements 12212 12213 GCC used to stand for the GNU C Compiler, but since the compiler 12214 supports several other languages aside from C, it now stands for the 12215 GNU Compiler Collection. 12216 12217 A list of [7]successful builds is updated as new information becomes 12218 available. 12219 12220 The GCC developers would like to thank the numerous people that have 12221 contributed new features, improvements, bug fixes, and other changes as 12222 well as test results to GCC. This [8]amazing group of volunteers is 12223 what makes GCC successful. 12224 12225 For additional information about GCC please refer to the [9]GCC project 12226 web site or contact the [10]GCC development mailing list. 12227 12228 To obtain GCC please use [11]our mirror sites or [12]our version 12229 control system. 12230 12231 12232 For questions related to the use of GCC, please consult these web 12233 pages and the [13]GCC manuals. If that fails, the 12234 [14]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 12235 web pages and the development of GCC are welcome on our developer 12236 list at [15]gcc (a] gcc.gnu.org. All of [16]our lists have public 12237 archives. 12238 12239 Copyright (C) [17]Free Software Foundation, Inc. Verbatim copying and 12240 distribution of this entire article is permitted in any medium, 12241 provided this notice is preserved. 12242 12243 These pages are [18]maintained by the GCC team. Last modified 12244 2022-10-26. 12245 12246 References 12247 12248 1. http://www.gnu.org/ 12249 2. http://gcc.gnu.org/gcc-4.2/changes.html 12250 3. http://gcc.gnu.org/gcc-4.2/changes.html 12251 4. http://gcc.gnu.org/gcc-4.2/changes.html 12252 5. http://gcc.gnu.org/gcc-4.2/changes.html 12253 6. http://gcc.gnu.org/gcc-4.2/changes.html 12254 7. http://gcc.gnu.org/gcc-4.2/buildstat.html 12255 8. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 12256 9. http://gcc.gnu.org/index.html 12257 10. mailto:gcc (a] gcc.gnu.org 12258 11. http://gcc.gnu.org/mirrors.html 12259 12. http://gcc.gnu.org/git.html 12260 13. https://gcc.gnu.org/onlinedocs/ 12261 14. mailto:gcc-help (a] gcc.gnu.org 12262 15. mailto:gcc (a] gcc.gnu.org 12263 16. https://gcc.gnu.org/lists.html 12264 17. https://www.fsf.org/ 12265 18. https://gcc.gnu.org/about.html 12266 ====================================================================== 12267 http://gcc.gnu.org/gcc-4.2/changes.html 12268 12269 GCC 4.2 Release Series 12270 Changes, New Features, and Fixes 12271 12272 Caveats 12273 12274 * GCC no longer accepts the -fshared-data option. This option has had 12275 no effect in any GCC 4 release; the targets to which the option 12276 used to apply had been removed before GCC 4.0. 12277 12278 General Optimizer Improvements 12279 12280 * New command-line options specify the possible relationships among 12281 parameters and between parameters and global data. For example, 12282 -fargument-noalias-anything specifies that arguments do not alias 12283 any other storage. 12284 Each language will automatically use whatever option is required by 12285 the language standard. You should not need to use these options 12286 yourself. 12287 12288 New Languages and Language specific improvements 12289 12290 * [1]OpenMP is now supported for the C, C++ and Fortran compilers. 12291 * New command-line options -fstrict-overflow and -Wstrict-overflow 12292 have been added. -fstrict-overflow tells the compiler that it may 12293 assume that the program follows the strict signed overflow 12294 semantics permitted for the language: for C and C++ this means that 12295 the compiler may assume that signed overflow does not occur. For 12296 example, a loop like 12297 for (i = 1; i > 0; i *= 2) 12298 12299 is presumably intended to continue looping until i overflows. With 12300 -fstrict-overflow, the compiler may assume that signed overflow 12301 will not occur, and transform this into an infinite loop. 12302 -fstrict-overflow is turned on by default at -O2, and may be 12303 disabled via -fno-strict-overflow. The -Wstrict-overflow option may 12304 be used to warn about cases where the compiler assumes that signed 12305 overflow will not occur. It takes five different levels: 12306 -Wstrict-overflow=1 to 5. See the [2]documentation for details. 12307 -Wstrict-overflow=1 is enabled by -Wall. 12308 * The new command-line option -fno-toplevel-reorder directs GCC to 12309 emit top-level functions, variables, and asm statements in the same 12310 order that they appear in the input file. This is intended to 12311 support existing code which relies on a particular ordering (for 12312 example, code which uses top-level asm statements to switch 12313 sections). For new code, it is generally better to use function and 12314 variable attributes. The -fno-toplevel-reorder option may be used 12315 for most cases which currently use -fno-unit-at-a-time. The 12316 -fno-unit-at-a-time option will be removed in some future version 12317 of GCC. If you know of a case which requires -fno-unit-at-a-time 12318 which is not fixed by -fno-toplevel-reorder, please open a bug 12319 report. 12320 12321 C family 12322 12323 * The pragma redefine_extname will now macro expand its tokens for 12324 compatibility with SunPRO. 12325 * In the next release of GCC, 4.3, -std=c99 or -std=gnu99 will direct 12326 GCC to handle inline functions as specified in the C99 standard. In 12327 preparation for this, GCC 4.2 will warn about any use of non-static 12328 inline functions in gnu99 or c99 mode. This new warning may be 12329 disabled with the new gnu_inline function attribute or the new 12330 -fgnu89-inline command-line option. Also, GCC 4.2 and later will 12331 define one of the preprocessor macros __GNUC_GNU_INLINE__ or 12332 __GNUC_STDC_INLINE__ to indicate the semantics of inline functions 12333 in the current compilation. 12334 * A new command-line option -Waddress has been added to warn about 12335 suspicious uses of memory addresses as, for example, using the 12336 address of a function in a conditional expression, and comparisons 12337 against the memory address of a string literal. This warning is 12338 enabled by -Wall. 12339 12340 C++ 12341 12342 * C++ visibility handling has been overhauled. 12343 Restricted visiblity is propagated from classes to members, from 12344 functions to local statics, and from templates and template 12345 arguments to instantiations, unless the latter has explicitly 12346 declared visibility. 12347 The visibility attribute for a class must come between the 12348 class-key and the name, not after the closing brace. 12349 Attributes are now allowed for enums and elaborated-type-specifiers 12350 that only declare a type. 12351 Members of the anonymous namespace are now local to a particular 12352 translation unit, along with any other declarations which use them, 12353 though they are still treated as having external linkage for 12354 language semantics. 12355 * The (undocumented) extension which permitted templates with default 12356 arguments to be bound to template template parameters with fewer 12357 parameters has been removed. For example: 12358 template <template <typename> class C> 12359 void f(C<double>) {} 12360 12361 template <typename T, typename U = int> 12362 struct S {}; 12363 12364 template void f(S<double>); 12365 12366 is no longer accepted by G++. The reason this code is not accepted 12367 is that S is a template with two parameters; therefore, it cannot 12368 be bound to C which has only one parameter. 12369 * The <?, >?, <?=, and >?= operators, deprecated in previous GCC 12370 releases, have been removed. 12371 * The command-line option -fconst-strings, deprecated in previous GCC 12372 releases, has been removed. 12373 * The configure variable enable-__cxa_atexit is now enabled by 12374 default for more targets. Enabling this variable is necessary in 12375 order for static destructors to be executed in the correct order, 12376 but it depends upon the presence of a non-standard C library in the 12377 target library in order to work. The variable is now enabled for 12378 more targets which are known to have suitable C libraries. 12379 * -Wextra will produce warnings for if statements with a semicolon as 12380 the only body, to catch code like: 12381 if (a); 12382 return 1; 12383 return 0; 12384 12385 To suppress the warning in valid cases, use { } instead. 12386 * The C++ front end now also produces strict aliasing warnings when 12387 -fstrict-aliasing -Wstrict-aliasing is in effect. 12388 12389 Runtime Library (libstdc++) 12390 12391 * Added support for TR1 <random>, <complex>, and C compatibility 12392 headers. In addition, a lock-free version of shared_ptr was 12393 contributed as part of Phillip Jordan's Google Summer of Code 12394 project on lock-free containers. 12395 * In association with the Summer of Code work on lock-free 12396 containers, the interface for atomic builtins was adjusted, 12397 creating simpler alternatives for non-threaded code paths. Also, 12398 usage was consolidated and all elements were moved from namespace 12399 std to namespace__gnu_cxx. Affected interfaces are the functions 12400 __exchange_and_add, __atomic_add, and the objects __mutex, 12401 __recursive_mutex, and __scoped_lock. 12402 * Support for versioning weak symbol names via namespace association 12403 was added. However, as this changes the names of exported symbols, 12404 this is turned off by default in the current ABI. Intrepid users 12405 can enable this feature by using 12406 --enable-symvers=gnu-versioned-namespace during configuration. 12407 * Revised, simplified, and expanded policy-based associative 12408 containers, including data types for tree and trie forms 12409 (basic_tree, tree, trie), lists (list_update), and both 12410 collision-chaining and probing hash-based containers 12411 (basic_hash_table, cc_hash_table, gp_hash_table). More details per 12412 the [3]documentation. 12413 * The implementation of the debug mode was modified, whereby the 12414 debug namespaces were nested inside of namespace std and namespace 12415 __gnu_cxx in order to resolve some long standing corner cases 12416 involving name lookup. Debug functionality from the policy-based 12417 data structures was consolidated and enabled with the single macro, 12418 _GLIBCXX_DEBUG. See PR 26142 for more information. 12419 * Added extensions for type traits: __conditional_type, 12420 __numeric_traits, __add_unsigned, __removed_unsigned, __enable_if. 12421 * Added a typelist implementation for compile-time meta-programming. 12422 Elements for typelist construction and operation can be found 12423 within namespace __gnu_cxx::typelist. 12424 * Added a new allocator, __gnu_cxx::throw_allocator, for testing 12425 exception-safety. 12426 * Enabled library-wide visibility control, allowing -fvisibility to 12427 be used. 12428 * Consolidated all nested namespaces and the conversion of 12429 __gnu_internal implementation-private details to anonymous 12430 namespaces whenever possible. 12431 * Implemented LWG resolutions DR 431 and DR 538. 12432 12433 Fortran 12434 12435 * Support for allocatable components has been added (TR 15581 and 12436 Fortran 2003). 12437 * Support for the Fortran 2003 streaming IO extension has been added. 12438 * The GNU Fortran compiler now uses 4-byte record markers by default 12439 for unformatted files to be compatible with g77 and most other 12440 compilers. The implementation allows for records greater than 2 GB 12441 and is compatible with several other compilers. Older versions of 12442 gfortran used 8-byte record markers by default (on most systems). 12443 In order to change the length of the record markers, e.g. to read 12444 unformatted files created by older gfortran versions, the 12445 [4]-frecord-marker=8 option can be used. 12446 12447 Java (GCJ) 12448 12449 * A new command-line option -static-libgcj has been added for targets 12450 that use a linker compatible with GNU Binutils. As its name 12451 implies, this causes libgcj to be linked statically. In some cases 12452 this causes the resulting executable to start faster and use less 12453 memory than if the shared version of libgcj were used. However 12454 caution should be used as it can also cause essential parts of the 12455 library to be omitted. Some of these issues are discussed in: 12456 [5]https://gcc.gnu.org/wiki/Statically_linking_libgcj 12457 * fastjar is no longer bundled with GCC. To build libgcj, you will 12458 need either InfoZIP (both zip and unzip) or an external jar 12459 program. In the former case, the GCC build will install a jar shell 12460 script that is based on InfoZIP and provides the same functionality 12461 as fastjar. 12462 12463 New Targets and Target Specific Improvements 12464 12465 IA-32/x86-64 12466 12467 * -mtune=generic can now be used to generate code running well on 12468 common x86 chips. This includes AMD Athlon, AMD Opteron, Intel 12469 Pentium-M, Intel Pentium 4 and Intel Core 2. 12470 * -mtune=native and -march=native will produce code optimized for the 12471 host architecture as detected using the cpuid instruction. 12472 * Added a new command-line option -fstackrealign and and 12473 __attribute__ ((force_align_arg_pointer)) to realign the stack at 12474 runtime. This allows functions compiled with a vector-aligned stack 12475 to be invoked from legacy objects that keep only word-alignment. 12476 12477 SPARC 12478 12479 * The default CPU setting has been changed from V7 to V9 in 32-bit 12480 mode on Solaris 7 and above. This is already the case in 64-bit 12481 mode. It can be overridden by specifying --with-cpu at configure 12482 time. 12483 * Back-end support of built-in functions for atomic memory access has 12484 been implemented. 12485 * Support for the Sun UltraSPARC T1 (Niagara) processor has been 12486 added. 12487 12488 M32C 12489 12490 * Various bug fixes have made some functions (notably, functions 12491 returning structures) incompatible with previous releases. 12492 Recompiling all libraries is recommended. Note that code quality 12493 has considerably improved since 4.1, making a recompile even more 12494 beneficial. 12495 12496 MIPS 12497 12498 * Added support for the Broadcom SB-1A core. 12499 12500 IA-64 12501 12502 * Added support for IA-64 data and control speculation. By default 12503 speculation is enabled only during second scheduler pass. A number 12504 of machine flags was introduced to control the usage of speculation 12505 for both scheduler passes. 12506 12507 HPPA 12508 12509 * Added Java language support (libffi and libjava) for 32-bit HP-UX 12510 11 target. 12511 12512 Obsolete Systems 12513 12514 Documentation improvements 12515 12516 PDF Documentation 12517 12518 * A make pdf target has been added to the top-level makefile, 12519 enabling automated production of PDF documentation files. 12520 (Front-ends external to GCC should modify their Make-lang.in file 12521 to add a lang.pdf: target.) 12522 12523 Other significant improvements 12524 12525 Build system improvements 12526 12527 * All the components of the compiler are now bootstrapped by default. 12528 This improves the resilience to bugs in the system compiler or 12529 binary compatibility problems, as well as providing better testing 12530 of GCC 4.2 itself. In addition, if you build the compiler from a 12531 combined tree, the assembler, linker, etc. will also be 12532 bootstrapped (i.e. built with themselves). 12533 You can disable this behavior, and go back to the pre-GCC 4.2 set 12534 up, by configuring GCC with --disable-bootstrap. 12535 * The rules that configure follows to find target tools resemble more 12536 closely the locations that the built compiler will search. In 12537 addition, you can use the new configure option --with-target-tools 12538 to specify where to find the target tools used during the build, 12539 without affecting what the built compiler will use. 12540 This can be especially useful when building packages of GCC. For 12541 example, you may want to build GCC with GNU as or ld, even if the 12542 resulting compiler to work with the native assembler and linker. To 12543 do so, you can use --with-target-tools to point to the native 12544 tools. 12545 12546 Incompatible changes to the build system 12547 12548 * Front-ends external to GCC should modify their Make-lang.in file to 12549 replace double-colon rules (e.g. dvi::) with normal rules (like 12550 lang.dvi:). Front-end makefile hooks do not use double-colon rules 12551 anymore. 12552 * Up to GCC 4.1, a popular way to specify the target tools used 12553 during the build was to create directories named gas, binutils, 12554 etc. in the build tree, and create links to the tools from there. 12555 This does not work any more when the compiler is bootstrapped. The 12556 new configure option --with-target-tools provides a better way to 12557 achieve the same effect, and works for all native and cross 12558 settings. 12559 12560 12561 For questions related to the use of GCC, please consult these web 12562 pages and the [6]GCC manuals. If that fails, the 12563 [7]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 12564 web pages and the development of GCC are welcome on our developer 12565 list at [8]gcc (a] gcc.gnu.org. All of [9]our lists have public archives. 12566 12567 Copyright (C) [10]Free Software Foundation, Inc. Verbatim copying and 12568 distribution of this entire article is permitted in any medium, 12569 provided this notice is preserved. 12570 12571 These pages are [11]maintained by the GCC team. Last modified 12572 2022-10-26. 12573 12574 References 12575 12576 1. http://gcc.gnu.org/projects/gomp/ 12577 2. https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html 12578 3. https://gcc.gnu.org/onlinedocs/libstdc++/ext/pb_ds/index.html 12579 4. https://gcc.gnu.org/onlinedocs/gfortran/Runtime-Options.html 12580 5. https://gcc.gnu.org/wiki/Statically_linking_libgcj 12581 6. https://gcc.gnu.org/onlinedocs/ 12582 7. mailto:gcc-help (a] gcc.gnu.org 12583 8. mailto:gcc (a] gcc.gnu.org 12584 9. https://gcc.gnu.org/lists.html 12585 10. https://www.fsf.org/ 12586 11. https://gcc.gnu.org/about.html 12587 ====================================================================== 12588 http://gcc.gnu.org/gcc-4.1/index.html 12589 12590 GCC 4.1 Release Series 12591 12592 (This release series is no longer supported.) 12593 12594 February 13, 2007 12595 12596 The [1]GNU project and the GCC developers are pleased to announce the 12597 release of GCC 4.1.2. 12598 12599 This release is a bug-fix release, containing fixes for regressions in 12600 GCC 4.1.1 relative to previous releases of GCC. 12601 12602 Release History 12603 12604 GCC 4.1.2 12605 February 13, 2007 ([2]changes) 12606 12607 GCC 4.1.1 12608 May 24, 2006 ([3]changes) 12609 12610 GCC 4.1.0 12611 February 28, 2006 ([4]changes) 12612 12613 References and Acknowledgements 12614 12615 GCC used to stand for the GNU C Compiler, but since the compiler 12616 supports several other languages aside from C, it now stands for the 12617 GNU Compiler Collection. 12618 12619 A list of [5]successful builds is updated as new information becomes 12620 available. 12621 12622 The GCC developers would like to thank the numerous people that have 12623 contributed new features, improvements, bug fixes, and other changes as 12624 well as test results to GCC. This [6]amazing group of volunteers is 12625 what makes GCC successful. 12626 12627 For additional information about GCC please refer to the [7]GCC project 12628 web site or contact the [8]GCC development mailing list. 12629 12630 To obtain GCC please use [9]our mirror sites or [10]our version control 12631 system. 12632 12633 12634 For questions related to the use of GCC, please consult these web 12635 pages and the [11]GCC manuals. If that fails, the 12636 [12]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 12637 web pages and the development of GCC are welcome on our developer 12638 list at [13]gcc (a] gcc.gnu.org. All of [14]our lists have public 12639 archives. 12640 12641 Copyright (C) [15]Free Software Foundation, Inc. Verbatim copying and 12642 distribution of this entire article is permitted in any medium, 12643 provided this notice is preserved. 12644 12645 These pages are [16]maintained by the GCC team. Last modified 12646 2022-10-26. 12647 12648 References 12649 12650 1. http://www.gnu.org/ 12651 2. http://gcc.gnu.org/gcc-4.1/changes.html#4.1.2 12652 3. http://gcc.gnu.org/gcc-4.1/changes.html 12653 4. http://gcc.gnu.org/gcc-4.1/changes.html 12654 5. http://gcc.gnu.org/gcc-4.1/buildstat.html 12655 6. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 12656 7. http://gcc.gnu.org/index.html 12657 8. mailto:gcc (a] gcc.gnu.org 12658 9. http://gcc.gnu.org/mirrors.html 12659 10. http://gcc.gnu.org/git.html 12660 11. https://gcc.gnu.org/onlinedocs/ 12661 12. mailto:gcc-help (a] gcc.gnu.org 12662 13. mailto:gcc (a] gcc.gnu.org 12663 14. https://gcc.gnu.org/lists.html 12664 15. https://www.fsf.org/ 12665 16. https://gcc.gnu.org/about.html 12666 ====================================================================== 12667 http://gcc.gnu.org/gcc-4.1/changes.html 12668 12669 GCC 4.1 Release Series 12670 Changes, New Features, and Fixes 12671 12672 The latest release in the 4.1 release series is [1]GCC 4.1.2. 12673 12674 Caveats 12675 12676 General Optimizer Improvements 12677 12678 * GCC now has infrastructure for inter-procedural optimizations and 12679 the following inter-procedural optimizations are implemented: 12680 + Profile guided inlining. When doing profile feedback guided 12681 optimization, GCC can now use the profile to make better 12682 informed decisions on whether inlining of a function is 12683 profitable or not. This means that GCC will no longer inline 12684 functions at call sites that are not executed very often, and 12685 that functions at hot call sites are more likely to be 12686 inlined. 12687 A new parameter min-inline-recursive-probability is also now 12688 available to throttle recursive inlining of functions with 12689 small average recursive depths. 12690 + Discovery of pure and const functions, a form of side-effects 12691 analysis. While older GCC releases could also discover such 12692 special functions, the new IPA-based pass runs earlier so that 12693 the results are available to more optimizers. The pass is also 12694 simply more powerful than the old one. 12695 + Analysis of references to static variables and type escape 12696 analysis, also forms of side-effects analysis. The results of 12697 these passes allow the compiler to be less conservative about 12698 call-clobbered variables and references. This results in more 12699 redundant loads being eliminated and in making static 12700 variables candidates for register promotion. 12701 + Improvement of RTL-based alias analysis. The results of type 12702 escape analysis are fed to the RTL type-based alias analyzer, 12703 allowing it to disambiguate more memory references. 12704 + Interprocedural constant propagation and function versioning. 12705 This pass looks for functions that are always called with the 12706 same constant value for one or more of the function arguments, 12707 and propagates those constants into those functions. 12708 + GCC will now eliminate static variables whose usage was 12709 optimized out. 12710 + -fwhole-program --combine can now be used to make all 12711 functions in program static allowing whole program 12712 optimization. As an exception, the main function and all 12713 functions marked with the new externally_visible attribute are 12714 kept global so that programs can link with runtime libraries. 12715 * GCC can now do a form of partial dead code elimination (PDCE) that 12716 allows code motion of expressions to the paths where the result of 12717 the expression is actually needed. This is not always a win, so the 12718 pass has been limited to only consider profitable cases. Here is an 12719 example: 12720 int foo (int *, int *); 12721 int 12722 bar (int d) 12723 { 12724 int a, b, c; 12725 b = d + 1; 12726 c = d + 2; 12727 a = b + c; 12728 if (d) 12729 { 12730 foo (&b, &c); 12731 a = b + c; 12732 } 12733 printf ("%d\n", a); 12734 } 12735 12736 The a = b + c can be sunk to right before the printf. Normal code 12737 sinking will not do this, it will sink the first one above into the 12738 else-branch of the conditional jump, which still gives you two 12739 copies of the code. 12740 * GCC now has a value range propagation pass. This allows the 12741 compiler to eliminate bounds checks and branches. The results of 12742 the pass can also be used to accurately compute branch 12743 probabilities. 12744 * The pass to convert PHI nodes to straight-line code (a form of 12745 if-conversion for GIMPLE) has been improved significantly. The two 12746 most significant improvements are an improved algorithm to 12747 determine the order in which the PHI nodes are considered, and an 12748 improvement that allow the pass to consider if-conversions of basic 12749 blocks with more than two predecessors. 12750 * Alias analysis improvements. GCC can now differentiate between 12751 different fields of structures in Tree-SSA's virtual operands form. 12752 This lets stores/loads from non-overlapping structure fields not 12753 conflict. A new algorithm to compute points-to sets was contributed 12754 that can allows GCC to see now that p->a and p->b, where p is a 12755 pointer to a structure, can never point to the same field. 12756 * Various enhancements to auto-vectorization: 12757 + Incrementally preserve SSA form when vectorizing. 12758 + Incrementally preserve loop-closed form when vectorizing. 12759 + Improvements to peeling for alignment: generate better code 12760 when the misalignment of an access is known at compile time, 12761 or when different accesses are known to have the same 12762 misalignment, even if the misalignment amount itself is 12763 unknown. 12764 + Consider dependence distance in the vectorizer. 12765 + Externalize generic parts of data reference analysis to make 12766 this analysis available to other passes. 12767 + Vectorization of conditional code. 12768 + Reduction support. 12769 * GCC can now partition functions in sections of hot and cold code. 12770 This can significantly improve performance due to better 12771 instruction cache locality. This feature works best together with 12772 profile feedback driven optimization. 12773 * A new pass to avoid saving of unneeded arguments to the stack in 12774 vararg functions if the compiler can prove that they will not be 12775 needed. 12776 * Transition of basic block profiling to tree level implementation 12777 has been completed. The new implementation should be considerably 12778 more reliable (hopefully avoiding profile mismatch errors when 12779 using -fprofile-use or -fbranch-probabilities) and can be used to 12780 drive higher level optimizations, such as inlining. 12781 The -ftree-based-profiling command-line option was removed and 12782 -fprofile-use now implies disabling old RTL level loop optimizer 12783 (-fno-loop-optimize). Speculative prefetching optimization 12784 (originally enabled by -fspeculative-prefetching) was removed. 12785 12786 New Languages and Language specific improvements 12787 12788 C and Objective-C 12789 12790 * The old Bison-based C and Objective-C parser has been replaced by a 12791 new, faster hand-written recursive-descent parser. 12792 12793 Ada 12794 12795 * The build infrastructure for the Ada runtime library and tools has 12796 been changed to be better integrated with the rest of the build 12797 infrastructure of GCC. This should make doing cross builds of Ada a 12798 bit easier. 12799 12800 C++ 12801 12802 * ARM-style name-injection of friend declarations is no longer the 12803 default. For example: 12804 struct S { 12805 friend void f(); 12806 }; 12807 12808 void g() { f(); } 12809 will not be accepted; instead a declaration of f will need to be 12810 present outside of the scope of S. The new -ffriend-injection 12811 option will enable the old behavior. 12812 * The (undocumented) extension which permitted templates with default 12813 arguments to be bound to template template parameters with fewer 12814 parameters has been deprecated, and will be removed in the next 12815 major release of G++. For example: 12816 template <template <typename> class C> 12817 void f(C<double>) {} 12818 12819 template <typename T, typename U = int> 12820 struct S {}; 12821 12822 template void f(S<double>); 12823 12824 makes use of the deprecated extension. The reason this code is not 12825 valid ISO C++ is that S is a template with two parameters; 12826 therefore, it cannot be bound to C which has only one parameter. 12827 12828 Runtime Library (libstdc++) 12829 12830 * Optimization work: 12831 + A new implementation of std::search_n is provided, better 12832 performing in case of random access iterators. 12833 + Added further efficient specializations of istream functions, 12834 i.e., character array and string extractors. 12835 + Other smaller improvements throughout. 12836 * Policy-based associative containers, designed for high-performance, 12837 flexibility and semantic safety are delivered in ext/pb_assoc. 12838 * A versatile string class, __gnu_cxx::__versa_string, providing 12839 facilities conforming to the standard requirements for 12840 basic_string, is delivered in <ext/vstring.h>. In particular: 12841 + Two base classes are provided: the default one avoids 12842 reference counting and is optimized for short strings; the 12843 alternate one, still uses it while improving in a few low 12844 level areas (e.g., alignment). See vstring_fwd.h for some 12845 useful typedefs. 12846 + Various algorithms have been rewritten (e.g., replace), the 12847 code streamlined and simple optimizations added. 12848 + Option 3 of DR 431 is implemented for both available bases, 12849 thus improving the support for stateful allocators. 12850 * As usual, many bugs have been fixed (e.g., libstdc++/13583, 12851 libstdc++/23953) and LWG resolutions put into effect for the first 12852 time (e.g., DR 280, DR 464, N1780 recommendations for DR 233, TR1 12853 Issue 6.19). The implementation status of TR1 is now tracked in the 12854 docs in tr1.html. 12855 12856 Objective-C++ 12857 12858 * A new language front end for Objective-C++ has been added. This 12859 language allows users to mix the object oriented features of 12860 Objective-C with those of C++. 12861 12862 Java (GCJ) 12863 12864 * Core library (libgcj) updates based on GNU Classpath 0.15 - 0.19 12865 features (plus some 0.20 bug-fixes) 12866 + Networking 12867 o The java.net.HttpURLConnection implementation no longer 12868 buffers the entire response body in memory. This means 12869 that response bodies larger than available memory can now 12870 be handled. 12871 + (N)IO 12872 o NIO FileChannel.map implementation, fast bulk put 12873 implementation for DirectByteBuffer (speeds up this 12874 method 10x). 12875 o FileChannel.lock() and FileChannel.force() implemented. 12876 + XML 12877 o gnu.xml fix for nodes created outside a namespace 12878 context. 12879 o Add support for output indenting and 12880 cdata-section-elements output instruction in 12881 xml.transform. 12882 o xml.xpath corrections for cases where elements/attributes 12883 might have been created in non-namespace-aware mode. 12884 Corrections to handling of XSL variables and minor 12885 conformance updates. 12886 + AWT 12887 o GNU JAWT implementation, the AWT Native Interface, which 12888 allows direct access to native screen resources from 12889 within a Canvas's paint method. GNU Classpath Examples 12890 comes with a Demo, see libjava/classpath/examples/README. 12891 o awt.datatransfer updated to 1.5 with support for 12892 FlavorEvents. The gtk+ awt peers now allow copy/paste of 12893 text, images, URIs/files and serialized objects with 12894 other applications and tracking clipboard change events 12895 with gtk+ 2.6 (for gtk+ 2.4 only text and serialized 12896 objects are supported). A GNU Classpath Examples 12897 datatransfer Demo was added to show the new 12898 functionality. 12899 o Split gtk+ awt peers event handling in two threads and 12900 improve gdk lock handling (solves several awt lock ups). 12901 o Speed up awt Image loading. 12902 o Better gtk+ scrollbar peer implementation when using gtk+ 12903 >= 2.6. 12904 o Handle image loading errors correctly for gdkpixbuf and 12905 MediaTracker. 12906 o Better handle GDK lock. Properly prefix gtkpeer native 12907 functions (cp_gtk). 12908 o GdkGraphics2D has been updated to use Cairo 0.5.x or 12909 higher. 12910 o BufferedImage and GtkImage rewrites. All image drawing 12911 operations should now work correctly (flipping requires 12912 gtk+ >= 2.6) 12913 o When gtk+ 2.6 or higher is installed the default log 12914 handler will produce stack traces whenever a WARNING, 12915 CRITICAL or ERROR message is produced. 12916 + Free Swing 12917 o The RepaintManager has been reworked for more efficient 12918 painting, especially for large GUIs. 12919 o The layout manager OverlayLayout has been implemented, 12920 the BoxLayout has been rewritten to make use of the 12921 SizeRequirements utility class and caching for more 12922 efficient layout. 12923 o Improved accessibility support. 12924 o Significant progress has been made in the implementation 12925 of the javax.swing.plaf.metal package, with most UI 12926 delegates in a working state now. Please test this with 12927 your own applications and provide feedback that will help 12928 us to improve this package. 12929 o The GUI demo (gnu.classpath.examples.swing.Demo) has been 12930 extended to highlight various features in our Free Swing 12931 implementation. And it includes a look and feel switcher 12932 for Metal (default), Ocean and GNU themes. 12933 o The javax.swing.plaf.multi package is now implemented. 12934 o Editing and several key actions for JTree and JTable were 12935 implemented. 12936 o Lots of icons and look and feel improvements for Free 12937 Swing basic and metal themes were added. Try running the 12938 GNU Classpath Swing Demo in examples 12939 (gnu.classpath.examples.swing.Demo) with: 12940 -Dswing.defaultlaf=javax.swing.plaf.basic.BasicLookAndFee 12941 l or 12942 -Dswing.defaultlaf=javax.swing.plaf.metal.MetalLookAndFee 12943 l 12944 o Start of styled text capabilites for java.swing.text. 12945 o DefaultMutableTreeNode pre-order, post-order, depth-first 12946 and breadth-first traversal enumerations implemented. 12947 o JInternalFrame colors and titlebar draw properly. 12948 o JTree is working up to par (icons, selection and keyboard 12949 traversal). 12950 o JMenus were made more compatible in visual and 12951 programmatic behavior. 12952 o JTable changeSelection and multiple selections 12953 implemented. 12954 o JButton and JToggleButton change states work properly 12955 now. 12956 o JFileChooser fixes. 12957 o revalidate() and repaint() fixes which make Free Swing 12958 much more responsive. 12959 o MetalIconFactory implemented. 12960 o Free Swing Top-Level Compatibility. JFrame, JDialog, 12961 JApplet, JInternalFrame, and JWindow are now 1.5 12962 compatible in the sense that you can call add() and 12963 setLayout() directly on them, which will have the same 12964 effect as calling getContentPane().add() and 12965 getContentPane().setLayout(). 12966 o The JTree interface has been completed. JTrees now 12967 recognizes mouse clicks and selections work. 12968 o BoxLayout works properly now. 12969 o Fixed GrayFilter to actually work. 12970 o Metal SplitPane implemented. 12971 o Lots of Free Swing text and editor stuff work now. 12972 + Free RMI and Corba 12973 o Andrew Watson, Vice President and Technical Director of 12974 the Object Management Group, has officially assigned us 12975 20 bit Vendor Minor Code Id: 0x47430 ("GC") that will 12976 mark remote classpath-specific system exceptions. 12977 Obtaining the VMCID means that GNU Classpath now is a 12978 recogniseable type of node in a highly interoperable 12979 CORBA world. 12980 o GNU Classpath now includes the first working draft to 12981 support the RMI over IIOP protocol. The current 12982 implementation is capable of remote invocations, 12983 transferring various Serializables and Externalizables 12984 via RMI-IIOP protocol. It can flatten graphs and, at 12985 least for the simple cases, is interoperable with 1.5 12986 JDKs. 12987 o org.omg.PortableInterceptor and related functionality in 12988 other packages is now implemented: 12989 # The sever and client interceptors work as required 12990 since 1.4. 12991 # The IOR interceptor works as needed for 1.5. 12992 o The org.omg.DynamicAny package is completed and passes 12993 the prepared tests. 12994 o The Portable Object Adapter should now support the output 12995 of the recent IDL to java compilers. These compilers now 12996 generate servants and not CORBA objects as before, making 12997 the output depend on the existing POA implementation. 12998 Completing POA means that such code can already be tried 12999 to run on Classpath. Our POA is tested for the following 13000 usager scenarios: 13001 # POA converts servant to the CORBA object. 13002 # Servant provides to the CORBA object. 13003 # POA activates new CORBA object with the given Object 13004 Id (byte array) that is later accessible for the 13005 servant. 13006 # During the first call, the ServantActivator provides 13007 servant for this and all subsequent calls on the 13008 current object. 13009 # During each call, the ServantLocator provides 13010 servant for this call only. 13011 # ServantLocator or ServantActivator forwards call to 13012 another server. 13013 # POA has a single servant, responsible for all 13014 objects. 13015 # POA has a default servant, but some objects are 13016 explicitly connected to they specific servants. 13017 The POA is verified using tests from the former 13018 cost.omg.org. 13019 o The CORBA implementation is now a working prototype that 13020 should support features up to 1.3 inclusive. We invite 13021 groups writing CORBA dependent applications to try 13022 Classpath implementation, reporting any possible bugs. 13023 The CORBA prototype is interoperable with Sun's 13024 implementation v 1.4, transferring object references, 13025 primitive types, narrow and wide strings, arrays, 13026 structures, trees, abstract interfaces and value types 13027 (feature of CORBA 2.3) between these two platforms. 13028 Remote exceptions are transferred and handled correctly. 13029 The stringified object references (IORs) from various 13030 sources are parsed as required. The transient (for 13031 current session) and permanent (till jre restart) 13032 redirections work. Both Little and Big Endian encoded 13033 messages are accepted. The implementation is verified 13034 using tests from the former cost.omg.org. The current 13035 release includes working examples (see the examples 13036 directory), demonstrating the client-server 13037 communication, using either CORBA Request or IDL-based 13038 stub (usually generated by a IDL to java compiler). These 13039 examples also show how to use the Classpath CORBA naming 13040 service. The IDL to java compiler is not yet written, but 13041 as our library must be compatible, it naturally accepts 13042 the output of other idlj implementations. 13043 + Misc 13044 o Updated TimeZone data against Olson tzdata2005l. 13045 o Make zip and jar packages UTF-8 clean. 13046 o "native" code builds and compiles (warning free) on 13047 Darwin and Solaris. 13048 o java.util.logging.FileHandler now rotates files. 13049 o Start of a generic JDWP framework in gnu/classpath/jdwp. 13050 This is unfinished, but feedback (at classpath (a] gnu.org) 13051 from runtime hackers is greatly appreciated. Although 13052 most of the work is currently being done around gcj/gij 13053 we want this framework to be as VM neutral as possible. 13054 Early design is described in: 13055 [2]https://gcc.gnu.org/ml/java/2005-05/msg00260.html 13056 o QT4 AWT peers, enable by giving configure 13057 --enable-qt-peer. Included, but not ready for production 13058 yet. They are explicitly disabled and not supported. But 13059 if you want to help with the development of these new 13060 features we are interested in feedback. You will have to 13061 explicitly enable them to try them out (and they will 13062 most likely contain bugs). 13063 o Documentation fixes all over the place. See 13064 [3]https://developer.classpath.org/doc/ 13065 13066 New Targets and Target Specific Improvements 13067 13068 IA-32/x86-64 13069 13070 * The x86-64 medium model (that allows building applications whose 13071 data segment exceeds 4GB) was redesigned to match latest ABI draft. 13072 New implementation split large datastructures into separate segment 13073 improving performance of accesses to small datastructures and also 13074 allows linking of small model libraries into medium model programs 13075 as long as the libraries are not accessing the large datastructures 13076 directly. Medium model is also supported in position independent 13077 code now. 13078 The ABI change results in partial incompatibility among medium 13079 model objects. Linking medium model libraries (or objects) compiled 13080 with new compiler into medium model program compiled with older 13081 will likely result in exceeding ranges of relocations. 13082 Binutils 2.16.91 or newer are required for compiling medium model 13083 now. 13084 13085 RS6000 (POWER/PowerPC) 13086 13087 * The AltiVec vector primitives in <altivec.h> are now implemented in 13088 a way that puts a smaller burden on the preprocessor, instead 13089 processing the "overloading" in the front ends. This should benefit 13090 compilation speed on AltiVec vector code. 13091 * AltiVec initializers now are generated more efficiently. 13092 * The popcountb instruction available on POWER5 now is generated. 13093 * The floating point round to integer instructions available on 13094 POWER5+ now is generated. 13095 * Floating point divides can be synthesized using the floating point 13096 reciprocal estimate instructions. 13097 * Double precision floating point constants are initialized as single 13098 precision values if they can be represented exactly. 13099 13100 S/390, zSeries and System z9 13101 13102 * Support for the IBM System z9 109 processor has been added. When 13103 using the -march=z9-109 option, the compiler will generate code 13104 making use of instructions provided by the extended immediate 13105 facility. 13106 * Support for 128-bit IEEE floating point has been added. When using 13107 the -mlong-double-128 option, the compiler will map the long double 13108 data type to 128-bit IEEE floating point. Using this option 13109 constitutes an ABI change, and requires glibc support. 13110 * Various changes to improve performance of generated code have been 13111 implemented, including: 13112 + In functions that do not require a literal pool, register %r13 13113 (which is traditionally reserved as literal pool pointer), can 13114 now be freely used for other purposes by the compiler. 13115 + More precise tracking of register use allows the compiler to 13116 generate more efficient function prolog and epilog code in 13117 certain cases. 13118 + The SEARCH STRING, COMPARE LOGICAL STRING, and MOVE STRING 13119 instructions are now used to implement C string functions. 13120 + The MOVE CHARACTER instruction with single byte overlap is now 13121 used to implement the memset function with non-zero fill byte. 13122 + The LOAD ZERO instructions are now used where appropriate. 13123 + The INSERT CHARACTERS UNDER MASK, STORE CHARACTERS UNDER MASK, 13124 and INSERT IMMEDIATE instructions are now used more frequently 13125 to optimize bitfield operations. 13126 + The BRANCH ON COUNT instruction is now used more frequently. 13127 In particular, the fact that a loop contains a subroutine call 13128 no longer prevents the compiler from using this instruction. 13129 + The compiler is now aware that all shift and rotate 13130 instructions implicitly truncate the shift count to six bits. 13131 * Back-end support for the following generic features has been 13132 implemented: 13133 + The full set of [4]built-in functions for atomic memory 13134 access. 13135 + The -fstack-protector feature. 13136 + The optimization pass avoiding unnecessary stores of incoming 13137 argument registers in functions with variable argument list. 13138 13139 SPARC 13140 13141 * The default code model in 64-bit mode has been changed from 13142 Medium/Anywhere to Medium/Middle on Solaris. 13143 * TLS support is disabled by default on Solaris prior to release 10. 13144 It can be enabled on TLS-capable Solaris 9 versions (4/04 release 13145 and later) by specifying --enable-tls at configure time. 13146 13147 MorphoSys 13148 13149 * Support has been added for this new architecture. 13150 13151 Obsolete Systems 13152 13153 Documentation improvements 13154 13155 Other significant improvements 13156 13157 * GCC can now emit code for protecting applications from 13158 stack-smashing attacks. The protection is realized by buffer 13159 overflow detection and reordering of stack variables to avoid 13160 pointer corruption. 13161 * Some built-in functions have been fortified to protect them against 13162 various buffer overflow (and format string) vulnerabilities. 13163 Compared to the mudflap bounds checking feature, the safe builtins 13164 have far smaller overhead. This means that programs built using 13165 safe builtins should not experience any measurable slowdown. 13166 13167 GCC 4.1.2 13168 13169 This is the [5]list of problem reports (PRs) from GCC's bug tracking 13170 system that are known to be fixed in the 4.1.2 release. This list might 13171 not be complete (that is, it is possible that some PRs that have been 13172 fixed are not listed here). 13173 13174 When generating code for a shared library, GCC now recognizes that 13175 global functions may be replaced when the program runs. Therefore, it 13176 is now more conservative in deducing information from the bodies of 13177 functions. For example, in this example: 13178 void f() {} 13179 void g() { 13180 try { f(); } 13181 catch (...) { 13182 cout << "Exception"; 13183 } 13184 } 13185 13186 G++ would previously have optimized away the catch clause, since it 13187 would have concluded that f cannot throw exceptions. Because users may 13188 replace f with another function in the main body of the program, this 13189 optimization is unsafe, and is no longer performed. If you wish G++ to 13190 continue to optimize as before, you must add a throw() clause to the 13191 declaration of f to make clear that it does not throw exceptions. 13192 13193 13194 For questions related to the use of GCC, please consult these web 13195 pages and the [6]GCC manuals. If that fails, the 13196 [7]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 13197 web pages and the development of GCC are welcome on our developer 13198 list at [8]gcc (a] gcc.gnu.org. All of [9]our lists have public archives. 13199 13200 Copyright (C) [10]Free Software Foundation, Inc. Verbatim copying and 13201 distribution of this entire article is permitted in any medium, 13202 provided this notice is preserved. 13203 13204 These pages are [11]maintained by the GCC team. Last modified 13205 2022-10-26. 13206 13207 References 13208 13209 1. http://gcc.gnu.org/gcc-4.1/changes.html#4.1.2 13210 2. https://gcc.gnu.org/ml/java/2005-05/msg00260.html 13211 3. https://developer.classpath.org/doc/ 13212 4. https://gcc.gnu.org/onlinedocs/gcc-4.1.0/gcc/Atomic-Builtins.html 13213 5. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.1.2 13214 6. https://gcc.gnu.org/onlinedocs/ 13215 7. mailto:gcc-help (a] gcc.gnu.org 13216 8. mailto:gcc (a] gcc.gnu.org 13217 9. https://gcc.gnu.org/lists.html 13218 10. https://www.fsf.org/ 13219 11. https://gcc.gnu.org/about.html 13220 ====================================================================== 13221 http://gcc.gnu.org/gcc-4.0/index.html 13222 13223 GCC 4.0 Release Series 13224 13225 (This release series is no longer supported.) 13226 13227 January 31, 2007 13228 13229 The [1]GNU project and the GCC developers are pleased to announce the 13230 release of GCC 4.0.4. 13231 13232 This release is a bug-fix release, containing fixes for regressions in 13233 GCC 4.0.3 relative to previous releases of GCC. 13234 13235 Release History 13236 13237 GCC 4.0.4 13238 January 31, 2007 ([2]changes) 13239 13240 GCC 4.0.3 13241 March 10, 2006 ([3]changes) 13242 13243 GCC 4.0.2 13244 September 28, 2005 ([4]changes) 13245 13246 GCC 4.0.1 13247 July 7, 2005 ([5]changes) 13248 13249 GCC 4.0.0 13250 April 20, 2005 ([6]changes) 13251 13252 References and Acknowledgements 13253 13254 GCC used to stand for the GNU C Compiler, but since the compiler 13255 supports several other languages aside from C, it now stands for the 13256 GNU Compiler Collection. 13257 13258 A list of [7]successful builds is updated as new information becomes 13259 available. 13260 13261 The GCC developers would like to thank the numerous people that have 13262 contributed new features, improvements, bug fixes, and other changes as 13263 well as test results to GCC. This [8]amazing group of volunteers is 13264 what makes GCC successful. 13265 13266 For additional information about GCC please refer to the [9]GCC project 13267 web site or contact the [10]GCC development mailing list. 13268 13269 To obtain GCC please use [11]our mirror sites, or [12]our version 13270 control system. 13271 13272 13273 For questions related to the use of GCC, please consult these web 13274 pages and the [13]GCC manuals. If that fails, the 13275 [14]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 13276 web pages and the development of GCC are welcome on our developer 13277 list at [15]gcc (a] gcc.gnu.org. All of [16]our lists have public 13278 archives. 13279 13280 Copyright (C) [17]Free Software Foundation, Inc. Verbatim copying and 13281 distribution of this entire article is permitted in any medium, 13282 provided this notice is preserved. 13283 13284 These pages are [18]maintained by the GCC team. Last modified 13285 2022-10-26. 13286 13287 References 13288 13289 1. http://www.gnu.org/ 13290 2. http://gcc.gnu.org/gcc-4.0/changes.html#4.0.4 13291 3. http://gcc.gnu.org/gcc-4.0/changes.html#4.0.3 13292 4. http://gcc.gnu.org/gcc-4.0/changes.html#4.0.2 13293 5. http://gcc.gnu.org/gcc-4.0/changes.html#4.0.1 13294 6. http://gcc.gnu.org/gcc-4.0/changes.html 13295 7. http://gcc.gnu.org/gcc-4.0/buildstat.html 13296 8. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 13297 9. http://gcc.gnu.org/index.html 13298 10. mailto:gcc (a] gcc.gnu.org 13299 11. http://gcc.gnu.org/mirrors.html 13300 12. http://gcc.gnu.org/git.html 13301 13. https://gcc.gnu.org/onlinedocs/ 13302 14. mailto:gcc-help (a] gcc.gnu.org 13303 15. mailto:gcc (a] gcc.gnu.org 13304 16. https://gcc.gnu.org/lists.html 13305 17. https://www.fsf.org/ 13306 18. https://gcc.gnu.org/about.html 13307 ====================================================================== 13308 http://gcc.gnu.org/gcc-4.0/changes.html 13309 13310 GCC 4.0 Release Series 13311 Changes, New Features, and Fixes 13312 13313 The latest release in the 4.0 release series is [1]GCC 4.0.4. 13314 13315 Caveats 13316 13317 * GCC now generates location lists by default when compiling with 13318 debug info and optimization. 13319 + GDB 6.0 and older crashes when it sees location lists. GDB 6.1 13320 or later is needed to debug binaries containing location 13321 lists. 13322 + When you are trying to view a value of a variable in a part of 13323 a function where it has no location (for example when the 13324 variable is no longer used and thus its location was used for 13325 something else) GDB will say that it is not available. 13326 You can disable generating location lists by -fno-var-tracking. 13327 * GCC no longer accepts the -fwritable-strings option. Use named 13328 character arrays when you need a writable string. 13329 * The options -freduce-all-givs and -fmove-all-movables have been 13330 discontinued. They were used to circumvent a shortcoming in the 13331 heuristics of the old loop optimization code with respect to common 13332 Fortran constructs. The new (tree) loop optimizer works differently 13333 and doesn't need those work-arounds. 13334 * The graph-coloring register allocator, formerly enabled by the 13335 option -fnew-ra, has been discontinued. 13336 * -I- has been deprecated. -iquote is meant to replace the need for 13337 this option. 13338 * The MIPS -membedded-pic and -mrnames options have been removed. 13339 * All MIPS targets now require the GNU assembler. In particular, IRIX 13340 configurations can no longer use the MIPSpro assemblers, although 13341 they do still support the MIPSpro linkers. 13342 * The SPARC option -mflat has been removed. 13343 * English-language diagnostic messages will now use Unicode quotation 13344 marks in UTF-8 locales. (Non-English messages already used the 13345 quotes appropriate for the language in previous releases.) If your 13346 terminal does not support UTF-8 but you are using a UTF-8 locale 13347 (such locales are the default on many GNU/Linux systems) then you 13348 should set LC_CTYPE=C in the environment to disable that locale. 13349 Programs that parse diagnostics and expect plain ASCII 13350 English-language messages should set LC_ALL=C. See [2]Markus Kuhn's 13351 explanation of Unicode quotation marks for more information. 13352 * The specs file is no longer installed on most platforms. Most users 13353 will be totally unaffected. However, if you are accustomed to 13354 editing the specs file yourself, you will now have to use the 13355 -dumpspecs option to generate the specs file, and then edit the 13356 resulting file. 13357 13358 General Optimizer Improvements 13359 13360 * The [3]tree ssa branch has been merged. This merge has brought in a 13361 completely new optimization framework based on a higher level 13362 intermediate representation than the existing RTL representation. 13363 Numerous new code transformations based on the new framework are 13364 available in GCC 4.0, including: 13365 + Scalar replacement of aggregates 13366 + Constant propagation 13367 + Value range propagation 13368 + Partial redundancy elimination 13369 + Load and store motion 13370 + Strength reduction 13371 + Dead store elimination 13372 + Dead and unreachable code elimination 13373 + [4]Autovectorization 13374 + Loop interchange 13375 + Tail recursion by accumulation 13376 Many of these passes outperform their counterparts from previous 13377 GCC releases. 13378 * [5]Swing Modulo Scheduling (SMS). An RTL level instruction 13379 scheduling optimization intended for loops that perform heavy 13380 computations. 13381 13382 New Languages and Language specific improvements 13383 13384 C family 13385 13386 * The sentinel attribute has been added to GCC. This function 13387 attribute allows GCC to warn when variadic functions such as execl 13388 are not NULL terminated. See the GCC manual for a complete 13389 description of its behavior. 13390 * Given __attribute__((alias("target"))) it is now an error if target 13391 is not a symbol, defined in the same translation unit. This also 13392 applies to aliases created by #pragma weak alias=target. This is 13393 because it's meaningless to define an alias to an undefined symbol. 13394 On Solaris, the native assembler would have caught this error, but 13395 GNU as does not. 13396 13397 C and Objective-C 13398 13399 * The -Wstrict-aliasing=2 option has been added. This warning catches 13400 all unsafe cases, but it may also give a warning for some cases 13401 that are safe. 13402 * The cast-as-lvalue, conditional-expression-as-lvalue and 13403 compound-expression-as-lvalue extensions, which were deprecated in 13404 3.3.4 and 3.4, have been removed. 13405 * The -fwritable-strings option, which was deprecated in 3.4, has 13406 been removed. 13407 * #pragma pack() semantics have been brought closer to those used by 13408 other compilers. This also applies to C++. 13409 * Taking the address of a variable with register storage is invalid 13410 in C. GCC now issues an error instead of a warning. 13411 * Arrays of incomplete element type are invalid in C. GCC now issues 13412 an error for such arrays. Declarations such as extern struct s x[]; 13413 (where struct s has not been defined) can be moved after the 13414 definition of struct s. Function parameters declared as arrays of 13415 incomplete type can instead be declared as pointers. 13416 13417 C++ 13418 13419 * When compiling without optimizations (-O0), the C++ front end is 13420 much faster than in any previous versions of GCC. Independent 13421 testers have measured speed-ups up to 25% in real-world production 13422 code, compared to the 3.4 family (which was already the fastest 13423 version to date). Upgrading from older versions might show even 13424 bigger improvements. 13425 * ELF visibility attributes can now be applied to a class type, so 13426 that it affects every member function of a class at once, without 13427 having to specify each individually: 13428 class __attribute__ ((visibility("hidden"))) Foo 13429 { 13430 int foo1(); 13431 void foo2(); 13432 }; 13433 The syntax is deliberately similar to the __declspec() system used 13434 by Microsoft Windows based compilers, allowing cross-platform 13435 projects to easily reuse their existing macro system for denoting 13436 exports and imports. By explicitly marking internal classes never 13437 used outside a binary as hidden, one can completely avoid PLT 13438 indirection overheads during their usage by the compiler. You can 13439 find out more about the advantages of this at 13440 [6]https://www.akkadia.org/drepper/dsohowto.pdf 13441 * The -fvisibility-inlines-hidden option has been added which marks 13442 all inlineable functions as having hidden ELF visibility, thus 13443 removing their symbol and typeinfo from the exported symbol table 13444 of the output ELF binary. Using this option can reduce the exported 13445 symbol count of template-heavy code by up to 40% with no code 13446 change at all, thus notably improving link and load times for the 13447 binary as well as a reduction in size of up to 10%. Also, check the 13448 new [7]-fvisibility option. 13449 * The compiler now uses the library interface specified by the [8]C++ 13450 ABI for thread-safe initialization of function-scope static 13451 variables. Most users should leave this alone, but embedded 13452 programmers may want to disable this by specifying 13453 -fno-threadsafe-statics for a small savings in code size. 13454 * Taking the address of an explicit register variable is no longer 13455 supported. Note that C++ allows taking the address of variables 13456 with register storage so this will continue to compile with a 13457 warning. For example, assuming that r0 is a machine register: 13458 register int foo asm ("r0"); 13459 register int bar; 13460 &foo; // error, no longer accepted 13461 &bar; // OK, with a warning 13462 * G++ has an undocumented extension to virtual function covariancy 13463 rules that allowed the overrider to return a type that was 13464 implicitly convertable to the overridden function's return type. 13465 For instance a function returning void * could be overridden by a 13466 function returning T *. This is now deprecated and will be removed 13467 in a future release. 13468 * The G++ minimum and maximum operators (<? and >?) and their 13469 compound forms (<?=) and >?=) have been deprecated and will be 13470 removed in a future version. Code using these operators should be 13471 modified to use std::min and std::max instead. 13472 * Declaration of nested classes of class templates as friends are 13473 supported: 13474 template <typename T> struct A { 13475 class B {}; 13476 }; 13477 class C { 13478 template <typename T> friend class A<T>::B; 13479 }; 13480 This complements the feature member functions of class templates as 13481 friends introduced in GCC 3.4.0. 13482 * When declaring a friend class using an unqualified name, classes 13483 outside the innermost non-class scope are not searched: 13484 class A; 13485 namespace N { 13486 class B { 13487 friend class A; // Refer to N::A which has not been declared yet 13488 // because name outside namespace N are not searched 13489 friend class ::A; // Refer to ::A 13490 }; 13491 } 13492 Hiding the friend name until declaration is still not implemented. 13493 * Friends of classes defined outside their namespace are correctly 13494 handled: 13495 namespace N { 13496 class A; 13497 } 13498 class N::A { 13499 friend class B; // Refer to N::B in GCC 4.0.0 13500 // but ::B in earlier versions of GCC 13501 }; 13502 13503 Runtime Library (libstdc++) 13504 13505 * Optimization work: 13506 + Added efficient specializations of istream functions for char 13507 and wchar_t. 13508 + Further performance tuning of strings, in particular wrt 13509 single-char append and getline. 13510 + iter_swap - and therefore most of the mutating algorithms - 13511 now makes an unqualified call to swap when the value_type of 13512 the two iterators is the same. 13513 * A large subset of the features in Technical Report 1 (TR1 for 13514 short) is experimentally delivered (i.e., no guarantees about the 13515 implementation are provided. In particular it is not promised that 13516 the library will remain link-compatible when code using TR1 is 13517 used): 13518 + General utilities such as reference_wrapper and shared_ptr. 13519 + Function objects, i.e., result_of, mem_fn, bind, function. 13520 + Support for metaprogramming. 13521 + New containers such as tuple, array, unordered_set, 13522 unordered_map, unordered_multiset, unordered_multimap. 13523 * As usual, many bugs have been fixed and LWG resolutions implemented 13524 for the first time (e.g., DR 409). 13525 13526 Java 13527 13528 * In order to prevent naming conflicts with other implementations of 13529 these tools, some GCJ binaries have been renamed: 13530 + rmic is now grmic, 13531 + rmiregistry is now grmiregistry, and 13532 + jar is now fastjar. 13533 In particular, these names were problematic for the jpackage.org 13534 packaging conventions which install symlinks in /usr/bin that point 13535 to the preferred versions of these tools. 13536 * The -findirect-dispatch argument to the compiler now works and 13537 generates code following a new "binary compatibility" ABI. Code 13538 compiled this way follows the binary compatibility rules of the 13539 Java Language Specification. 13540 * libgcj now has support for using GCJ as a JIT, using the 13541 gnu.gcj.jit family of system properties. 13542 * libgcj can now find a shared library corresponding to the bytecode 13543 representation of a class. See the documentation for the new 13544 gcj-dbtool program, and the new gnu.gcj.precompiled.db.path system 13545 property. 13546 * There have been many improvements to the class library. Here are 13547 some highlights: 13548 + Much more of AWT and Swing exist. 13549 + Many new packages and classes were added, including 13550 java.util.regex, java.net.URI, javax.crypto, 13551 javax.crypto.interfaces, javax.crypto.spec, javax.net, 13552 javax.net.ssl, javax.security.auth, 13553 javax.security.auth.callback, javax.security.auth.login, 13554 javax.security.auth.x500, javax.security.sasl, org.ietf.jgss, 13555 javax.imageio, javax.imageio.event, javax.imageio.spi, 13556 javax.print, javax.print.attribute, 13557 javax.print.attribute.standard, javax.print.event, and 13558 javax.xml 13559 + Updated SAX and DOM, and imported GNU JAXP 13560 13561 Fortran 13562 13563 * A new [9]Fortran front end has replaced the aging GNU Fortran 77 13564 front end. The new front end supports Fortran 90 and Fortran 95. It 13565 may not yet be as stable as the old Fortran front end. 13566 13567 Ada 13568 13569 * Ada (with tasking and Zero Cost Exceptions) is now available on 13570 many more targets, including but not limited to: alpha-linux, 13571 hppa-hpux, hppa-linux, powerpc-darwin, powerpc-linux, s390-linux, 13572 s390x-linux, sparc-linux. 13573 * Some of the new Ada 2005 features are now implemented like 13574 Wide_Wide_Character and Ada.Containers. 13575 * Many bugs have been fixed, tools and documentation improved. 13576 * To compile Ada from the sources, install an older working Ada 13577 compiler and then use --enable-languages=ada at configuration time, 13578 since the Ada front end is not currently activated by default. See 13579 the [10]Installing GCC for details. 13580 13581 New Targets and Target Specific Improvements 13582 13583 H8/300 13584 13585 * The frame layout has changed. In the new layout, the prologue of a 13586 function first saves registers and then allocate space for locals, 13587 resulting in an 1% improvement on code size. 13588 13589 IA-32/x86-64 (AMD64) 13590 13591 * The acos, asin, drem, exp10, exp2, expm1, fmod, ilogb, log10, 13592 log1p, log2, logb and tan mathematical builtins (and their float 13593 and long double variants) are now implemented as inline x87 13594 intrinsics when using -ffast-math. 13595 * The ceil, floor, nearbyint, rint and trunc mathematical builtins 13596 (and their float and long double variants) are now implemented as 13597 inline x87 intrinsics when using -ffast-math. 13598 * The x87's fsincos instruction is now used automatically with 13599 -ffast-math when calculating both the sin and cos of the same 13600 argument. 13601 * Instruction selection for multiplication and division by constants 13602 has been improved. 13603 13604 IA-64 13605 13606 * Floating point division, integer division and sqrt are now inlined, 13607 resulting in significant performance improvements on some codes. 13608 13609 MIPS 13610 13611 * Division by zero checks now use conditional traps if the target 13612 processor supports them. This decreases code size by one word per 13613 division operation. The old behavior (branch and break) can be 13614 obtained either at configure time by passing --with-divide=breaks 13615 to configure or at runtime by passing -mdivide-breaks to GCC. 13616 * Support for MIPS64 paired-single instructions has been added. It is 13617 enabled by -mpaired-single and can be accessed using both the 13618 target-independent vector extensions and new MIPS-specific built-in 13619 functions. 13620 * Support for the MIPS-3D ASE has been added. It is enabled by 13621 -mips3d and provides new MIPS-3D-specific built-in functions. 13622 * The -mexplicit-relocs option now supports static n64 code (as is 13623 used, for example, in 64-bit linux kernels). -mexplicit-relocs 13624 should now be feature-complete and is enabled by default when GCC 13625 is configured to use a compatible assembler. 13626 * Support for the NEC VR4130 series has been added. This support 13627 includes the use of VR-specific instructions and a new VR4130 13628 scheduler. Full VR4130 support can be selected with -march=vr4130 13629 while code for any ISA can be tuned for the VR4130 using 13630 -mtune=vr4130. There is also a new -mvr4130-align option that 13631 produces better schedules at the cost of increased code size. 13632 * Support for the Broadcom SB-1 has been extended. There is now an 13633 SB-1 scheduler as well as support for the SB-1-specific 13634 paired-single instructions. Full SB-1 support can be selected with 13635 -march=sb1 while code for any ISA can be optimized for the SB-1 13636 using -mtune=sb1. 13637 * The compiler can now work around errata in R4000, R4400, VR4120 and 13638 VR4130 processors. These workarounds are enabled by -mfix-r4000, 13639 -mfix-r4400, -mfix-vr4120 and -mfix-vr4130 respectively. The VR4120 13640 and VR4130 workarounds need binutils 2.16 or above. 13641 * IRIX shared libraries are now installed into the standard library 13642 directories: o32 libraries go into lib/, n32 libraries go into 13643 lib32/ and n64 libraries go into lib64/. 13644 * The compiler supports a new -msym32 option. It can be used to 13645 optimize n64 code in which all symbols are known to have 32-bit 13646 values. 13647 13648 S/390 and zSeries 13649 13650 * New command-line options help to generate code intended to run in 13651 an environment where stack space is restricted, e.g. Linux kernel 13652 code: 13653 + -mwarn-framesize and -mwarn-dynamicstack trigger compile-time 13654 warnings for single functions that require large or dynamic 13655 stack frames. 13656 + -mstack-size and -mstack-guard generate code that checks for 13657 stack overflow at run time. 13658 + -mpacked-stack generates code that reduces the stack frame 13659 size of many functions by reusing unneeded parts of the stack 13660 bias area. 13661 * The -msoft-float option now ensures that generated code never 13662 accesses floating point registers. 13663 * The s390x-ibm-tpf target now fully supports C++, including 13664 exceptions and threads. 13665 * Various changes to improve performance of the generated code have 13666 been implemented, including: 13667 + GCC now uses sibling calls where possible. 13668 + Condition code handling has been optimized, allowing GCC to 13669 omit redundant comparisons in certain cases. 13670 + The cost function guiding many optimizations has been refined 13671 to more accurately represent the z900 and z990 processors. 13672 + The ADD LOGICAL WITH CARRY and SUBTRACT LOGICAL WITH BORROW 13673 instructions are now used to avoid conditional branches in 13674 certain cases. 13675 + The back end now uses the LEGITIMIZE_RELOAD_ADDRESS feature to 13676 optimize address arithmetic required to access large stack 13677 frames. 13678 + GCC now makes more efficient use of memory-to-memory type 13679 instructions (MVC, CLC, ...). 13680 + More precise tracking of special register use allows better 13681 instruction scheduling, in particular of the function prologue 13682 and epilogue sequences. 13683 + The Java front end now generates inline code to implement 13684 integer division, instead of calling library routines. 13685 13686 SPARC 13687 13688 * The options -mv8, -msparclite, -mcypress, -msupersparc, -mf930 and 13689 -mf934 have been removed. They have been replaced with -mcpu=xxx. 13690 * The internal model used to estimate the relative cost of each 13691 instruction has been updated. It is expected to give better results 13692 on recent UltraSPARC processors. 13693 * Code generation for function prologues and epilogues has been 13694 improved, resulting in better scheduling and allowing multiple exit 13695 points in functions. 13696 * Support for Sun's Visual Instruction Set (VIS) has been enhanced. 13697 It is enabled by -mvis and provides new built-in functions for VIS 13698 instructions on UltraSPARC processors. 13699 * The option -mapp-regs has been turned on by default on Solaris too. 13700 13701 NetWare 13702 13703 * Novell NetWare (on ix86, no other hardware platform was ever really 13704 supported by this OS) has been re-enabled and the ABI supported by 13705 GCC has been brought into sync with that of MetroWerks CodeWarrior 13706 (the ABI previously supported was that of some Unix systems, which 13707 NetWare never tried to support). 13708 13709 Obsolete Systems 13710 13711 Support for a number of older systems has been declared obsolete in GCC 13712 4.0. Unless there is activity to revive them, the next release of GCC 13713 will have their sources permanently removed. 13714 13715 All GCC ports for the following processor architectures have been 13716 declared obsolete: 13717 * Intel i860 13718 * Ubicom IP2022 13719 * National Semiconductor NS32K (ns32k) 13720 * Texas Instruments TMS320C[34]x 13721 13722 Also, those for some individual systems have been obsoleted: 13723 * SPARC family 13724 + SPARClite-based systems (sparclite-*-coff, sparclite-*-elf, 13725 sparc86x-*-elf) 13726 + OpenBSD 32-bit (sparc-*-openbsd*) 13727 13728 Documentation improvements 13729 13730 Other significant improvements 13731 13732 * Location lists are now generated by default when compiling with 13733 debug info and optimization. Location lists provide more accurate 13734 debug info about locations of variables and they allow debugging 13735 code compiled with -fomit-frame-pointer. 13736 * The -fvisibility option has been added which allows the default ELF 13737 visibility of all symbols to be set per compilation and the new 13738 #pragma GCC visibility preprocessor command allows the setting of 13739 default ELF visibility for a region of code. Using 13740 -fvisibility=hidden especially in combination with the new 13741 -fvisibility-inlines-hidden can yield substantial improvements in 13742 output binary quality including avoiding PLT indirection overheads, 13743 reduction of the exported symbol count by up to 60% (with resultant 13744 improvements to link and load times), better scope for the 13745 optimizer to improve code and up to a 20% reduction in binary size. 13746 Using these options correctly yields a binary with a similar symbol 13747 count to a Windows DLL. 13748 Perhaps more importantly, this new feature finally allows (with 13749 careful planning) complete avoidance of symbol clashes when 13750 manually loading shared objects with RTLD_GLOBAL, thus finally 13751 solving problems many projects such as python were forced to use 13752 RTLD_LOCAL for (with its resulting issues for C++ correctness). You 13753 can find more information about using these options at 13754 [11]https://gcc.gnu.org/wiki/Visibility. 13755 __________________________________________________________________ 13756 13757 GCC 4.0.1 13758 13759 This is the [12]list of problem reports (PRs) from GCC's bug tracking 13760 system that are known to be fixed in the 4.0.1 release. This list might 13761 not be complete (that is, it is possible that some PRs that have been 13762 fixed are not listed here). 13763 13764 GCC 4.0.2 13765 13766 This is the [13]list of problem reports (PRs) from GCC's bug tracking 13767 system that are known to be fixed in the 4.0.2 release. This list might 13768 not be complete (that is, it is possible that some PRs that have been 13769 fixed are not listed here). 13770 13771 Unfortunately, due to a release engineering failure, this release has a 13772 regression on Solaris that will affect some C++ programs. We suggest 13773 that Solaris users apply a [14]patch that corrects the problem. Users 13774 who do not wish to apply the patch should explicitly link C++ programs 13775 with the -pthreads option, even if they do not use threads. This 13776 problem has been corrected in the current 4.0 branch sources and will 13777 not be present in GCC 4.0.3. 13778 13779 GCC 4.0.3 13780 13781 Starting with this release, the function getcontext is recognized by 13782 the compiler as having the same semantics as the setjmp function. In 13783 particular, the compiler will ensure that all registers are dead before 13784 calling such a function and will emit a warning about the variables 13785 that may be clobbered after the second return from the function. 13786 13787 GCC 4.0.4 13788 13789 This is the [15]list of problem reports (PRs) from GCC's bug tracking 13790 system that are known to be fixed in the 4.0.4 release. This list might 13791 not be complete (that is, it is possible that some PRs that have been 13792 fixed are not listed here). 13793 13794 The 4.0.4 release is provided for those that require a high degree of 13795 binary compatibility with previous 4.0.x releases. For most users, the 13796 GCC team recommends that version 4.1.1 or later be used instead." 13797 13798 13799 For questions related to the use of GCC, please consult these web 13800 pages and the [16]GCC manuals. If that fails, the 13801 [17]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 13802 web pages and the development of GCC are welcome on our developer 13803 list at [18]gcc (a] gcc.gnu.org. All of [19]our lists have public 13804 archives. 13805 13806 Copyright (C) [20]Free Software Foundation, Inc. Verbatim copying and 13807 distribution of this entire article is permitted in any medium, 13808 provided this notice is preserved. 13809 13810 These pages are [21]maintained by the GCC team. Last modified 13811 2022-10-26. 13812 13813 References 13814 13815 1. http://gcc.gnu.org/gcc-4.0/changes.html#4.0.4 13816 2. https://www.cl.cam.ac.uk/~mgk25/ucs/quotes.html 13817 3. http://gcc.gnu.org/projects/tree-ssa/ 13818 4. http://gcc.gnu.org/projects/tree-ssa/vectorization.html 13819 5. http://gcc.gnu.org/news/sms.html 13820 6. https://www.akkadia.org/drepper/dsohowto.pdf 13821 7. http://gcc.gnu.org/gcc-4.0/changes.html#visibility 13822 8. https://itanium-cxx-abi.github.io/cxx-abi/ 13823 9. http://gcc.gnu.org/fortran/ 13824 10. https://gcc.gnu.org/install/ 13825 11. https://gcc.gnu.org/wiki/Visibility 13826 12. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.0.1 13827 13. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.0.2 13828 14. https://gcc.gnu.org/ml/gcc-cvs/2005-09/msg00984.html 13829 15. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.0.4 13830 16. https://gcc.gnu.org/onlinedocs/ 13831 17. mailto:gcc-help (a] gcc.gnu.org 13832 18. mailto:gcc (a] gcc.gnu.org 13833 19. https://gcc.gnu.org/lists.html 13834 20. https://www.fsf.org/ 13835 21. https://gcc.gnu.org/about.html 13836 ====================================================================== 13837 http://gcc.gnu.org/gcc-3.4/index.html 13838 13839 GCC 3.4 Release Series 13840 13841 (This release series is no longer supported.) 13842 13843 May 26, 2006 13844 13845 The [1]GNU project and the GCC developers are pleased to announce the 13846 release of GCC 3.4.6. 13847 13848 This release is a bug-fix release, containing fixes for regressions in 13849 GCC 3.4.4 relative to previous releases of GCC. This is the last of the 13850 3.4.x series. 13851 13852 The GCC 3.4 release series includes numerous [2]new features, 13853 improvements, bug fixes, and other changes, thanks to an [3]amazing 13854 group of volunteers. 13855 13856 Release History 13857 13858 GCC 3.4.6 13859 March 6, 2006 ([4]changes) 13860 13861 GCC 3.4.5 13862 November 30, 2005 ([5]changes) 13863 13864 GCC 3.4.4 13865 May 18, 2005 ([6]changes) 13866 13867 GCC 3.4.3 13868 November 4, 2004 ([7]changes) 13869 13870 GCC 3.4.2 13871 September 6, 2004 ([8]changes) 13872 13873 GCC 3.4.1 13874 July 1, 2004 ([9]changes) 13875 13876 GCC 3.4.0 13877 April 18, 2004 ([10]changes) 13878 13879 References and Acknowledgements 13880 13881 GCC used to stand for the GNU C Compiler, but since the compiler 13882 supports several other languages aside from C, it now stands for the 13883 GNU Compiler Collection. 13884 13885 A list of [11]successful builds is updated as new information becomes 13886 available. 13887 13888 The GCC developers would like to thank the numerous people that have 13889 contributed new features, improvements, bug fixes, and other changes as 13890 well as test results to GCC. This [12]amazing group of volunteers is 13891 what makes GCC successful. 13892 13893 For additional information about GCC please refer to the [13]GCC 13894 project web site or contact the [14]GCC development mailing list. 13895 13896 To obtain GCC please use [15]our mirror sites, or [16]our version 13897 control system. 13898 13899 13900 For questions related to the use of GCC, please consult these web 13901 pages and the [17]GCC manuals. If that fails, the 13902 [18]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 13903 web pages and the development of GCC are welcome on our developer 13904 list at [19]gcc (a] gcc.gnu.org. All of [20]our lists have public 13905 archives. 13906 13907 Copyright (C) [21]Free Software Foundation, Inc. Verbatim copying and 13908 distribution of this entire article is permitted in any medium, 13909 provided this notice is preserved. 13910 13911 These pages are [22]maintained by the GCC team. Last modified 13912 2022-10-26. 13913 13914 References 13915 13916 1. http://www.gnu.org/ 13917 2. http://gcc.gnu.org/gcc-3.4/changes.html 13918 3. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 13919 4. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.6 13920 5. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.5 13921 6. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.4 13922 7. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.3 13923 8. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.2 13924 9. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.1 13925 10. http://gcc.gnu.org/gcc-3.4/changes.html 13926 11. http://gcc.gnu.org/gcc-3.4/buildstat.html 13927 12. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 13928 13. http://gcc.gnu.org/index.html 13929 14. mailto:gcc (a] gcc.gnu.org 13930 15. http://gcc.gnu.org/mirrors.html 13931 16. http://gcc.gnu.org/git.html 13932 17. https://gcc.gnu.org/onlinedocs/ 13933 18. mailto:gcc-help (a] gcc.gnu.org 13934 19. mailto:gcc (a] gcc.gnu.org 13935 20. https://gcc.gnu.org/lists.html 13936 21. https://www.fsf.org/ 13937 22. https://gcc.gnu.org/about.html 13938 ====================================================================== 13939 http://gcc.gnu.org/gcc-3.4/changes.html 13940 13941 GCC 3.4 Release Series 13942 Changes, New Features, and Fixes 13943 13944 The final release in the 3.4 release series is [1]GCC 3.4.6. The series 13945 is now closed. 13946 13947 GCC 3.4 has [2]many improvements in the C++ front end. Before reporting 13948 a bug, please make sure it's really GCC, and not your code, that is 13949 broken. 13950 13951 Caveats 13952 13953 * GNU Make is now required to build GCC. 13954 * With -nostdinc the preprocessor used to ignore both standard 13955 include paths and include paths contained in environment variables. 13956 It was neither documented nor intended that environment variable 13957 paths be ignored, so this has been corrected. 13958 * GCC no longer accepts the options -fvolatile, -fvolatile-global and 13959 -fvolatile-static. It is unlikely that they worked correctly in any 13960 3.x release. 13961 * GCC no longer ships <varargs.h>. Use <stdarg.h> instead. 13962 * Support for all the systems [3]obsoleted in GCC 3.3 has been 13963 removed from GCC 3.4. See below for a [4]list of systems which are 13964 obsoleted in this release. 13965 * GCC now requires an ISO C90 (ANSI C89) C compiler to build. K&R C 13966 compilers will not work. 13967 * The implementation of the [5]MIPS ABIs has changed. As a result, 13968 the code generated for certain MIPS targets will not be binary 13969 compatible with earlier releases. 13970 * In previous releases, the MIPS port had a fake "hilo" register with 13971 the user-visible name accum. This register has been removed. 13972 * The implementation of the [6]SPARC ABIs has changed. As a result, 13973 the code generated will not be binary compatible with earlier 13974 releases in certain cases. 13975 * The configure option --enable-threads=pthreads has been removed; 13976 use --enable-threads=posix instead, which should have the same 13977 effect. 13978 * Code size estimates used by inlining heuristics for C, Objective-C, 13979 C++ and Java have been redesigned significantly. As a result the 13980 parameters of -finline-insns, --param max-inline-insns-single and 13981 --param max-inline-insns-auto need to be reconsidered. 13982 * --param max-inline-slope and --param min-inline-insns have been 13983 removed; they are not needed for the new bottom-up inlining 13984 heuristics. 13985 * The new unit-at-a-time compilation scheme has several compatibility 13986 issues: 13987 + The order in which functions, variables, and top-level asm 13988 statements are emitted may have changed. Code relying on some 13989 particular ordering needs to be updated. The majority of such 13990 top-level asm statements can be replaced by section 13991 attributes. 13992 + Unreferenced static variables and functions are removed. This 13993 may result in undefined references when an asm statement 13994 refers to the variable/function directly. In that case either 13995 the variable/function shall be listed in asm statement operand 13996 or in the case of top-level asm statements the attribute used 13997 shall be used to force function/variable to be always output 13998 and considered as a possibly used by unknown code. 13999 For variables the attribute is accepted only by GCC 3.4 and 14000 newer, while for earlier versions it is sufficient to use 14001 unused to silence warnings about the variables not being 14002 referenced. To keep code portable across different GCC 14003 versions, you can use appropriate preprocessor conditionals. 14004 + Static functions now can use non-standard passing conventions 14005 that may break asm statements calling functions directly. 14006 Again the attribute used shall be used to prevent this 14007 behavior. 14008 As a temporary workaround, -fno-unit-at-a-time can be used, but 14009 this scheme may not be supported by future releases of GCC. 14010 * GCC 3.4 automatically places zero-initialized variables in the .bss 14011 section on some operating systems. Versions of GNU Emacs up to (and 14012 including) 21.3 will not work correctly when using this 14013 optimization; you can use -fno-zero-initialized-in-bss to disable 14014 it. 14015 * If GCC 3.4 is configured with --enable-threads=posix (the default 14016 on most targets that support pthreads) then _REENTRANT will be 14017 defined unconditionally by some libstdc++ headers. C++ code which 14018 relies on that macro to detect whether multi-threaded code is being 14019 compiled might change in meaning, possibly resulting in linker 14020 errors for single-threaded programs. Affected users of [7]Boost 14021 should compile single-threaded code with -DBOOST_DISABLE_THREADS. 14022 See Bugzilla for [8]more information. 14023 14024 General Optimizer Improvements 14025 14026 * Usability of the profile feedback and coverage testing has been 14027 improved. 14028 + Performance of profiled programs has been improved by faster 14029 profile merging code. 14030 + Better use of the profile feedback for optimization (loop 14031 unrolling and loop peeling). 14032 + File locking support allowing fork() calls and parallel runs 14033 of profiled programs. 14034 + Coverage file format has been redesigned. 14035 + gcov coverage tool has been improved. 14036 + make profiledbootstrap available to build a faster compiler. 14037 Experiments made on i386 hardware showed an 11% speedup on -O0 14038 and a 7.5% speedup on -O2 compilation of a [9]large C++ 14039 testcase. 14040 + New value profiling pass enabled via -fprofile-values 14041 + New value profile transformations pass enabled via -fvpt aims 14042 to optimize some code sequences by exploiting knowledge about 14043 value ranges or other properties of the operands. At the 14044 moment a conversion of expensive divisions into cheaper 14045 operations has been implemented. 14046 + New -fprofile-generate and -fprofile-use command-line options 14047 to simplify the use of profile feedback. 14048 * A new unit-at-a-time compilation scheme for C, Objective-C, C++ and 14049 Java which is enabled via -funit-at-a-time (and implied by -O2). In 14050 this scheme a whole file is parsed first and optimized later. The 14051 following basic inter-procedural optimizations are implemented: 14052 + Removal of unreachable functions and variables 14053 + Discovery of local functions (functions with static linkage 14054 whose address is never taken) 14055 + On i386, these local functions use register parameter passing 14056 conventions. 14057 + Reordering of functions in topological order of the call graph 14058 to enable better propagation of optimizing hints (such as the 14059 stack alignments needed by functions) in the back end. 14060 + Call graph based out-of-order inlining heuristics which allows 14061 to limit overall compilation unit growth (--param 14062 inline-unit-growth). 14063 Overall, the unit-at-a-time scheme produces a 1.3% improvement for 14064 the SPECint2000 benchmark on the i386 architecture (AMD Athlon 14065 CPU). 14066 * More realistic code size estimates used by inlining for C, 14067 Objective-C, C++ and Java. The growth of large functions can now be 14068 limited via --param large-function-insns and --param 14069 large-function-growth. 14070 * A new cfg-level loop optimizer pass replaces the old loop unrolling 14071 pass and adds two other loop transformations -- loop peeling and 14072 loop unswitching -- and also uses the profile feedback to limit 14073 code growth. (The three optimizations are enabled by 14074 -funroll-loops, -fpeel-loops and -funswitch-loops flags, 14075 respectively). 14076 The old loop unroller still can be enabled by -fold-unroll-loops 14077 and may produce better code in some cases, especially when the 14078 webizer optimization pass is not run. 14079 * A new web construction pass enabled via -fweb (and implied by -O3) 14080 improves the quality of register allocation, CSE, first scheduling 14081 pass and some other optimization passes by avoiding re-use of 14082 pseudo registers with non-overlapping live ranges. The pass almost 14083 always improves code quality but does make debugging difficult and 14084 thus is not enabled by default by -O2 14085 The pass is especially effective as cleanup after code duplication 14086 passes, such as the loop unroller or the tracer. 14087 * Experimental implementations of superblock or trace scheduling in 14088 the second scheduling pass can be enabled via 14089 -fsched2-use-superblocks and -fsched2-use-traces, respectively. 14090 14091 New Languages and Language specific improvements 14092 14093 Ada 14094 14095 * The Ada front end has been updated to include numerous bug fixes 14096 and enhancements. These include: 14097 + Improved project file support 14098 + Additional set of warnings about potential wrong code 14099 + Improved error messages 14100 + Improved code generation 14101 + Improved cross reference information 14102 + Improved inlining 14103 + Better run-time check elimination 14104 + Better error recovery 14105 + More efficient implementation of unbounded strings 14106 + Added features in GNAT.Sockets, GNAT.OS_Lib, GNAT.Debug_Pools, 14107 ... 14108 + New GNAT.xxxx packages (e.g. GNAT.Strings, 14109 GNAT.Exception_Action) 14110 + New pragmas 14111 + New -gnatS switch replacing gnatpsta 14112 + Implementation of new Ada features (in particular limited 14113 with, limited aggregates) 14114 14115 C/Objective-C/C++ 14116 14117 * Precompiled headers are now supported. Precompiled headers can 14118 dramatically speed up compilation of some projects. There are some 14119 known defects in the current precompiled header implementation that 14120 will result in compiler crashes in relatively rare situations. 14121 Therefore, precompiled headers should be considered a "technology 14122 preview" in this release. Read the manual for details about how to 14123 use precompiled headers. 14124 * File handling in the preprocessor has been rewritten. GCC no longer 14125 gets confused by symlinks and hardlinks, and now has a correct 14126 implementation of #import and #pragma once. These two directives 14127 have therefore been un-deprecated. 14128 * The undocumented extension that allowed C programs to have a label 14129 at the end of a compound statement, which has been deprecated since 14130 GCC 3.0, has been removed. 14131 * The cast-as-lvalue extension has been removed for C++ and 14132 deprecated for C and Objective-C. In particular, code like this: 14133 int i; 14134 (char) i = 5; 14135 14136 or this: 14137 char *p; 14138 ((int *) p)++; 14139 14140 is no longer accepted for C++ and will not be accepted for C and 14141 Objective-C in a future version. 14142 * The conditional-expression-as-lvalue extension has been deprecated 14143 for C and Objective-C. In particular, code like this: 14144 int a, b, c; 14145 (a ? b : c) = 2; 14146 14147 will not be accepted for C and Objective-C in a future version. 14148 * The compound-expression-as-lvalue extension has been deprecated for 14149 C and Objective-C. In particular, code like this: 14150 int a, b; 14151 (a, b) = 2; 14152 14153 will not be accepted for C and Objective-C in a future version. A 14154 possible non-intrusive workaround is the following: 14155 (*(a, &b)) = 2; 14156 14157 * Several [10]built-in functions such as __builtin_popcount for 14158 counting bits, finding the highest and lowest bit in a word, and 14159 parity have been added. 14160 * The -fwritable-strings option has been deprecated and will be 14161 removed. 14162 * Many C math library functions are now recognized as built-ins and 14163 optimized. 14164 * The C, C++, and Objective-C compilers can now handle source files 14165 written in any character encoding supported by the host C library. 14166 The default input character set is taken from the current locale, 14167 and may be overridden with the -finput-charset command line option. 14168 In the future we will add support for inline encoding markers. 14169 14170 C++ 14171 14172 * G++ is now much closer to full conformance to the ISO/ANSI C++ 14173 standard. This means, among other things, that a lot of invalid 14174 constructs which used to be accepted in previous versions will now 14175 be rejected. It is very likely that existing C++ code will need to 14176 be fixed. This document lists some of the most common issues. 14177 * A hand-written recursive-descent C++ parser has replaced the 14178 YACC-derived C++ parser from previous GCC releases. The new parser 14179 contains much improved infrastructure needed for better parsing of 14180 C++ source codes, handling of extensions, and clean separation 14181 (where possible) between proper semantics analysis and parsing. The 14182 new parser fixes many bugs that were found in the old parser. 14183 * You must now use the typename and template keywords to disambiguate 14184 dependent names, as required by the C++ standard. 14185 struct K { 14186 typedef int mytype_t; 14187 }; 14188 14189 template <class T1> struct A { 14190 template <class T2> struct B { 14191 void callme(void); 14192 }; 14193 14194 template <int N> void bar(void) 14195 { 14196 // Use 'typename' to tell the parser that T1::mytype_t names 14197 // a type. This is needed because the name is dependent (in 14198 // this case, on template parameter T1). 14199 typename T1::mytype_t x; 14200 x = 0; 14201 } 14202 }; 14203 14204 template <class T> void template_func(void) 14205 { 14206 // Use 'template' to prefix member templates within 14207 // dependent types (a has type A<T>, which depends on 14208 // the template parameter T). 14209 A<T> a; 14210 a.template bar<0>(); 14211 14212 // Use 'template' to tell the parser that B is a nested 14213 // template class (dependent on template parameter T), and 14214 // 'typename' because the whole A<T>::B<int> is 14215 // the name of a type (again, dependent). 14216 typename A<T>::template B<int> b; 14217 b.callme(); 14218 } 14219 14220 void non_template_func(void) 14221 { 14222 // Outside of any template class or function, no names can be 14223 // dependent, so the use of the keyword 'typename' and 'template' 14224 // is not needed (and actually forbidden). 14225 A<K> a; 14226 a.bar<0>(); 14227 A<K>::B<float> b; 14228 b.callme(); 14229 } 14230 * In a template definition, unqualified names will no longer find 14231 members of a dependent base (as specified by [temp.dep]/3 in the 14232 C++ standard). For example, 14233 template <typename T> struct B { 14234 int m; 14235 int n; 14236 int f (); 14237 int g (); 14238 }; 14239 int n; 14240 int g (); 14241 template <typename T> struct C : B<T> { 14242 void h () 14243 { 14244 m = 0; // error 14245 f (); // error 14246 n = 0; // ::n is modified 14247 g (); // ::g is called 14248 } 14249 }; 14250 You must make the names dependent, e.g. by prefixing them with 14251 this->. Here is the corrected definition of C<T>::h, 14252 template <typename T> void C<T>::h () 14253 { 14254 this->m = 0; 14255 this->f (); 14256 this->n = 0 14257 this->g (); 14258 } 14259 As an alternative solution (unfortunately not backwards compatible 14260 with GCC 3.3), you may use using declarations instead of this->: 14261 template <typename T> struct C : B<T> { 14262 using B<T>::m; 14263 using B<T>::f; 14264 using B<T>::n; 14265 using B<T>::g; 14266 void h () 14267 { 14268 m = 0; 14269 f (); 14270 n = 0; 14271 g (); 14272 } 14273 }; 14274 * In templates, all non-dependent names are now looked up and bound 14275 at definition time (while parsing the code), instead of later when 14276 the template is instantiated. For instance: 14277 void foo(int); 14278 14279 template <int> struct A { 14280 static void bar(void){ 14281 foo('a'); 14282 } 14283 }; 14284 14285 void foo(char); 14286 14287 int main() 14288 { 14289 A<0>::bar(); // Calls foo(int), used to call foo(char). 14290 } 14291 14292 * In an explicit instantiation of a class template, you must use 14293 class or struct before the template-id: 14294 template <int N> 14295 class A {}; 14296 14297 template A<0>; // error, not accepted anymore 14298 template class A<0>; // OK 14299 * The "named return value" and "implicit typename" extensions have 14300 been removed. 14301 * Default arguments in function types have been deprecated and will 14302 be removed. 14303 * ARM-style name-injection of friend declarations has been deprecated 14304 and will be removed. For example: struct S { friend void f(); }; 14305 void g() { f(); } will not be accepted by future versions of G++; 14306 instead a declaration of "f" will need to be present outside of the 14307 scope of "S". 14308 * Covariant returns are implemented for all but varadic functions 14309 that require an adjustment. 14310 * When -pedantic is used, G++ now issues errors about spurious 14311 semicolons. For example, 14312 namespace N {}; // Invalid semicolon. 14313 void f() {}; // Invalid semicolon. 14314 * G++ no longer accepts attributes for a declarator after the 14315 initializer associated with that declarator. For example, 14316 X x(1) __attribute__((...)); 14317 is no longer accepted. Instead, use: 14318 X x __attribute__((...)) (1); 14319 * Inside the scope of a template class, the name of the class itself 14320 can be treated as either a class or a template. So GCC used to 14321 accept the class name as argument of type template, and template 14322 template parameter. However this is not C++ standard compliant. Now 14323 the name is not treated as a valid template template argument 14324 unless you qualify the name by its scope. For example, the code 14325 below no longer compiles. 14326 template <template <class> class TT> class X {}; 14327 template <class T> class Y { 14328 X<Y> x; // Invalid, Y is always a type template parameter. 14329 }; 14330 The valid code for the above example is 14331 X< ::Y> x; // Valid. 14332 (Notice the space between < and : to prevent GCC to interpret this 14333 as a digraph for [.) 14334 * Friend declarations that refer to template specializations are 14335 rejected if the template has not already been declared. For 14336 example, 14337 template <typename T> 14338 class C { 14339 friend void f<> (C&); 14340 }; 14341 is rejected. You must first declare f as a template, 14342 template <typename T> 14343 void f(T); 14344 * In case of friend declarations, every name used in the friend 14345 declaration must be accessible at the point of that declaration. 14346 Previous versions of G++ used to be less strict about this and 14347 allowed friend declarations for private class members, for example. 14348 See the ISO C++ Standard Committee's [11]defect report #209 for 14349 details. 14350 * Declaration of member functions of class templates as friends are 14351 supported. For example, 14352 template <typename T> struct A { 14353 void f(); 14354 }; 14355 class C { 14356 template <typename T> friend void A<T>::f(); 14357 }; 14358 * You must use template <> to introduce template specializations, as 14359 required by the standard. For example, 14360 template <typename T> 14361 struct S; 14362 14363 struct S<int> { }; 14364 is rejected. You must write, 14365 template <> struct S<int> {}; 14366 * G++ used to accept code like this, 14367 struct S { 14368 int h(); 14369 void f(int i = g()); 14370 int g(int i = h()); 14371 }; 14372 This behavior is not mandated by the standard. Now G++ issues an 14373 error about this code. To avoid the error, you must move the 14374 declaration of g before the declaration of f. The default arguments 14375 for g must be visible at the point where it is called. 14376 * The C++ ABI Section 3.3.3 specifications for the array construction 14377 routines __cxa_vec_new2 and __cxa_vec_new3 were changed to return 14378 NULL when the allocator argument returns NULL. These changes are 14379 incorporated into the libstdc++ runtime library. 14380 * Using a name introduced by a typedef in a friend declaration or in 14381 an explicit instantiation is now rejected, as specified by the ISO 14382 C++ standard. 14383 class A; 14384 typedef A B; 14385 class C { 14386 friend class B; // error, no typedef name here 14387 friend B; // error, friend always needs class/struct/enum 14388 friend class A; // OK 14389 }; 14390 14391 template <int> class Q {}; 14392 typedef Q<0> R; 14393 template class R; // error, no typedef name here 14394 template class Q<0>; // OK 14395 * When allocating an array with a new expression, GCC used to allow 14396 parentheses around the type name. This is actually ill-formed and 14397 it is now rejected: 14398 int* a = new (int)[10]; // error, not accepted anymore 14399 int* a = new int[10]; // OK 14400 * When binding an rvalue of class type to a reference, the copy 14401 constructor of the class must be accessible. For instance, consider 14402 the following code: 14403 class A 14404 { 14405 public: 14406 A(); 14407 14408 private: 14409 A(const A&); // private copy ctor 14410 }; 14411 14412 A makeA(void); 14413 void foo(const A&); 14414 14415 void bar(void) 14416 { 14417 foo(A()); // error, copy ctor is not accessible 14418 foo(makeA()); // error, copy ctor is not accessible 14419 14420 A a1; 14421 foo(a1); // OK, a1 is a lvalue 14422 } 14423 This might be surprising at first sight, especially since most 14424 popular compilers do not correctly implement this rule ([12]further 14425 details). 14426 * When forming a pointer to member or a pointer to member function, 14427 access checks for class visibility (public, protected, private) are 14428 now performed using the qualifying scope of the name itself. This 14429 is better explained with an example: 14430 class A 14431 { 14432 public: 14433 void pub_func(); 14434 protected: 14435 void prot_func(); 14436 private: 14437 void priv_func(); 14438 }; 14439 14440 class B : public A 14441 { 14442 public: 14443 void foo() 14444 { 14445 &A::pub_func; // OK, pub_func is accessible through A 14446 &A::prot_func; // error, cannot access prot_func through A 14447 &A::priv_func; // error, cannot access priv_func through A 14448 14449 &B::pub_func; // OK, pub_func is accessible through B 14450 &B::prot_func; // OK, can access prot_func through B (within B) 14451 &B::priv_func; // error, cannot access priv_func through B 14452 } 14453 }; 14454 14455 Runtime Library (libstdc++) 14456 14457 * Optimization work: 14458 + Streamlined streambuf, filebuf, separate synched with C 14459 Standard I/O streambuf. 14460 + All formatted I/O now uses cached locale information. 14461 + STL optimizations (memory/speed for list, red-black trees as 14462 used by sets and maps). 14463 + More use of GCC builtins. 14464 + String optimizations (avoid contention on 14465 increment/decrement-and-test of the reference count in the 14466 empty-string object, constructor from input_iterators 14467 speedup). 14468 * Static linkage size reductions. 14469 * Large File Support (files larger than 2 GB on 32-bit systems). 14470 * Wide character and variable encoding filebuf work (UTF-8, Unicode). 14471 * Generic character traits. 14472 * Also support wchar_t specializations on Mac OS 10.3.x, FreeBSD 5.x, 14473 Solaris 2.7 and above, AIX 5.x, Irix 6.5. 14474 * The allocator class is now standard-conformant, and two additional 14475 extension allocators have been added, mt_alloc and 14476 bitmap_allocator. 14477 * PCH support: -include bits/stdc++.h (2x compile speedup). 14478 * Rewrote __cxa_demangle with support for C++ style allocators. 14479 * New debug modes for STL containers and iterators. 14480 * Testsuite rewrite: five times as many tests, plus increasingly 14481 sophisticated tests, including I/O, MT, multi-locale, wide and 14482 narrow characters. 14483 * Use current versions of GNU "autotools" for build/configuration. 14484 14485 Objective-C 14486 14487 * The Objective-C front end has been updated to include the numerous 14488 bug fixes and enhancements previously available only in Apple's 14489 version of GCC. These include: 14490 + Structured exception (@try... @catch... @finally, @throw) and 14491 synchronization (@synchronized) support. These are accessible 14492 via the -fobjc-exceptions switch; as of this writing, they may 14493 only be used in conjunction with -fnext-runtime on Mac OS X 14494 10.3 and later. See [13]Options Controlling Objective-C 14495 Dialect for more information. 14496 + An overhaul of @encode logic. The C99 _Bool and C++ bool type 14497 may now be encoded as 'B'. In addition, the back-end/codegen 14498 dependencies have been removed. 14499 + An overhaul of message dispatch construction, ensuring that 14500 the various receiver types (and casts thereof) are handled 14501 properly, and that correct diagnostics are issued. 14502 + Support for "Zero-Link" (-fzero-link) and "Fix-and-Continue" 14503 (-freplace-objc-classes) debugging modes, currently available 14504 on Mac OS X 10.3 and later. See [14]Options Controlling 14505 Objective-C Dialect for more information. 14506 + Access to optimized runtime entry points (-fno-nil-receivers ) 14507 on the assumption that message receivers are never nil. This 14508 is currently available on Mac OS X 10.3 and later. See 14509 [15]Options Controlling Objective-C Dialect for more 14510 information. 14511 14512 Java 14513 14514 * Compiling a .jar file will now cause non-.class entries to be 14515 automatically compiled as resources. 14516 * libgcj has been ported to Darwin. 14517 * Jeff Sturm has adapted Jan Hubicka's call graph optimization code 14518 to gcj. 14519 * libgcj has a new gcjlib URL type; this lets URLClassLoader load 14520 code from shared libraries. 14521 * libgcj has been much more completely merged with [16]GNU Classpath. 14522 * Class loading is now much more correct; in particular the caller's 14523 class loader is now used when that is required. 14524 * [17]Eclipse 2.x will run out of the box using gij. 14525 * Parts of java.nio have been implemented. Direct and indirect 14526 buffers work, as do fundamental file and socket operations. 14527 * java.awt has been improved, though it is still not ready for 14528 general use. 14529 * The HTTP protocol handler now uses HTTP/1.1 and can handle the POST 14530 method. 14531 * The MinGW port has matured. Enhancements include socket timeout 14532 support, thread interruption, improved Runtime.exec() handling and 14533 support for accented characters in filenames. 14534 14535 Fortran 14536 14537 * Fortran improvements are listed in the [18]Fortran documentation. 14538 14539 New Targets and Target Specific Improvements 14540 14541 Alpha 14542 14543 * Several [19]built-in functions have been added such as 14544 __builtin_alpha_zap to allow utilizing the more obscure 14545 instructions of the CPU. 14546 * Parameter passing of complex arguments has changed to match the 14547 ABI. This change is incompatible with previous GCC versions, but 14548 does fix compatibility with the Tru64 compiler and several corner 14549 cases where GCC was incompatible with itself. 14550 14551 ARM 14552 14553 * Nicolas Pitre has contributed his hand-coded floating-point support 14554 code for ARM. It is both significantly smaller and faster than the 14555 existing C-based implementation, even when building applications 14556 for Thumb. The arm-elf configuration has been converted to use the 14557 new code. 14558 * Support for the Intel's iWMMXt architecture, a second generation 14559 XScale processor, has been added. Enabled at run time with the 14560 -mcpu=iwmmxt command line switch. 14561 * A new ARM target has been added: arm-wince-pe. This is similar to 14562 the arm-pe target, but it defaults to using the APCS32 ABI. 14563 * The existing ARM pipeline description has been converted to the use 14564 the [20]DFA processor pipeline model. There is not much change in 14565 code performance, but the description is now [21]easier to 14566 understand. 14567 * Support for the Cirrus EP9312 Maverick floating point co-processor 14568 added. Enabled at run time with the -mcpu=ep9312 command line 14569 switch. Note however that the multilibs to support this chip are 14570 currently disabled in gcc/config/arm/t-arm-elf, so if you want to 14571 enable their production you will have to uncomment the entries in 14572 that file. 14573 14574 H8/300 14575 14576 * Support for long long has been added. 14577 * Support for saveall attribute has been added. 14578 * Pavel Pisa contributed hand-written 32-bit-by-32-bit division code 14579 for H8/300H and H8S, which is much faster than the previous 14580 implementation. 14581 * A lot of small performance improvements. 14582 14583 IA-32/AMD64 (x86-64) 14584 14585 * Tuning for K8 (AMD Opteron/Athlon64) core is available via 14586 -march=k8 and -mcpu=k8. 14587 * Scalar SSE code generation carefully avoids reformatting penalties, 14588 hidden dependencies and minimizes the number of uops generated on 14589 both Intel and AMD CPUs. 14590 * Vector MMX and SSE operands are now passed in registers to improve 14591 performance and match the argument passing convention used by the 14592 Intel C++ Compiler. As a result it is not possible to call 14593 functions accepting vector arguments compiled by older GCC version. 14594 * Conditional jump elimination is now more aggressive on modern CPUs. 14595 * The Athlon ports has been converted to use the DFA processor 14596 pipeline description. 14597 * Optimization of indirect tail calls is now possible in a similar 14598 fashion as direct sibcall optimization. 14599 * Further small performance improvements. 14600 * -m128bit-long-double is now less buggy. 14601 * __float128 support in 64-bit compilation. 14602 * Support for data structures exceeding 2GB in 64-bit mode. 14603 * -mcpu has been renamed to -mtune. 14604 14605 IA-64 14606 14607 * Tuning code for the Itanium 2 processor has been added. The 14608 generation of code tuned for Itanium 2 (option -mtune=itanium2) is 14609 enabled by default now. To generate code tuned for Itanium 1 the 14610 option -mtune=itanium1 should be used. 14611 * [22]DFA processor pipeline descriptions for the IA-64 processors 14612 have been added. This resulted in about 3% improvement on the 14613 SPECInt2000 benchmark for Itanium 2. 14614 * Instruction bundling for the IA-64 processors has been rewritten 14615 using the DFA pipeline hazard recognizer. It resulted in about 60% 14616 compiler speedup on the SPECInt2000 C programs. 14617 14618 M32R 14619 14620 * Support for the M32R/2 processor has been added by Renesas. 14621 * Support for an M32R GNU/Linux target and PIC code generation has 14622 been added by Renesas. 14623 14624 M68000 14625 14626 * Bernardo Innocenti (Develer S.r.l.) has contributed the 14627 m68k-uclinux target, based on former work done by Paul Dale 14628 (SnapGear Inc.). Code generation for the ColdFire processors family 14629 has been enhanced and extended to support the MCF 53xx and MCF 54xx 14630 cores, integrating former work done by Peter Barada (Motorola). 14631 14632 MIPS 14633 14634 Processor-specific changes 14635 14636 * Support for the RM7000 and RM9000 processors has been added. It can 14637 be selected using the -march compiler option and should work with 14638 any MIPS I (mips-*) or MIPS III (mips64-*) configuration. 14639 * Support for revision 2 of the MIPS32 ISA has been added. It can be 14640 selected with the command-line option -march=mips32r2. 14641 * There is a new option, -mfix-sb1, to work around certain SB-1 14642 errata. 14643 14644 Configuration 14645 14646 * It is possible to customize GCC using the following configure-time 14647 options: 14648 + --with-arch, which specifies the default value of the -march 14649 option. 14650 + --with-tune, which specifies the default value of the -mtune 14651 option. 14652 + --with-abi, which specifies the default ABI. 14653 + --with-float=soft, which tells GCC to use software floating 14654 point by default. 14655 + --with-float=hard, which tells GCC to use hardware floating 14656 point by default. 14657 * A 64-bit GNU/Linux port has been added. The associated 14658 configurations are mips64-linux-gnu and mips64el-linux-gnu. 14659 * The 32-bit GNU/Linux port now supports Java. 14660 * The IRIX 6 configuration now supports the o32 ABI and will build 14661 o32 multilibs by default. This support is compatible with both 14662 binutils and the SGI tools, but note that several features, 14663 including debugging information and DWARF2 exception handling, are 14664 only available when using the GNU assembler. Use of the GNU 14665 assembler and linker (version 2.15 or above) is strongly 14666 recommended. 14667 * The IRIX 6 configuration now supports 128-bit long doubles. 14668 * There are two new RTEMS-specific configurations, mips-rtems and 14669 mipsel-rtems. 14670 * There are two new *-elf configurations, mipsisa32r2-elf and 14671 mipsisa32r2el-elf. 14672 14673 General 14674 14675 * Several [23]ABI bugs have been fixed. Unfortunately, these changes 14676 will break binary compatibility with earlier releases. 14677 * GCC can now use explicit relocation operators when generating 14678 -mabicalls code. This behavior is controlled by -mexplicit-relocs 14679 and can have several performance benefits. For example: 14680 + It allows for more optimization of GOT accesses, including 14681 better scheduling and redundancy elimination. 14682 + It allows sibling calls to be implemented as jumps. 14683 + n32 and n64 leaf functions can use a call-clobbered global 14684 pointer instead of $28. 14685 + The code to set up $gp can be removed from functions that 14686 don't need it. 14687 * A new option, -mxgot, allows the GOT to be bigger than 64k. This 14688 option is equivalent to the assembler's -xgot option and should be 14689 used instead of -Wa,-xgot. 14690 * Frame pointer elimination is now supported when generating 64-bit 14691 MIPS16 code. 14692 * Inline block moves have been optimized to take more account of 14693 alignment information. 14694 * Many internal changes have been made to the MIPS port, mostly aimed 14695 at reducing the reliance on assembler macros. 14696 14697 PowerPC 14698 14699 * GCC 3.4 releases have a number of fixes for PowerPC and PowerPC64 14700 [24]ABI incompatibilities regarding the way parameters are passed 14701 during functions calls. These changes may result in incompatibility 14702 between code compiled with GCC 3.3 and GCC 3.4. 14703 14704 PowerPC Darwin 14705 14706 * Support for shared/dylib gcc libraries has been added. It is 14707 enabled by default on powerpc-apple-darwin7.0.0 and up. 14708 * Libgcj is enabled by default. On systems older than 14709 powerpc-apple-darwin7.0.0 you need to install dlcompat. 14710 * 128-bit IBM extended precision format support added for long 14711 double. 14712 14713 PowerPC64 GNU/Linux 14714 14715 * By default, PowerPC64 GNU/Linux now uses natural alignment of 14716 structure elements. The old four byte alignment for double, with 14717 special rules for a struct starting with a double, can be chosen 14718 with -malign-power. This change may result in incompatibility 14719 between code compiled with GCC 3.3 and GCC 3.4. 14720 * -mabi=altivec is now the default rather than -mabi=no-altivec. 14721 * 128-bit IBM extended precision format support added for long 14722 double. 14723 14724 S/390 and zSeries 14725 14726 * New command-line options allow to specify the intended execution 14727 environment for generated code: 14728 + -mesa/-mzarch allows to specify whether to generate code 14729 running in ESA/390 mode or in z/Architecture mode (this is 14730 applicable to 31-bit code only). 14731 + -march allows to specify a minimum processor architecture 14732 level (g5, g6, z900, or z990). 14733 + -mtune allows to specify which processor to tune for. 14734 * It is possible to customize GCC using the following configure-time 14735 options: 14736 + --with-mode, which specifies whether to default to assuming 14737 ESA/390 or z/Architecture mode. 14738 + --with-arch, which specifies the default value of the -march 14739 option. 14740 + --with-tune, which specifies the default value of the -mtune 14741 option. 14742 * Support for the z990 processor has been added, and can be selected 14743 using -march=z990 or -mtune=z990. This includes instruction 14744 scheduling tuned for the superscalar instruction pipeline of the 14745 z990 processor as well as support for all new instructions provided 14746 by the long-displacement facility. 14747 * Support to generate 31-bit code optimized for zSeries processors 14748 (running in ESA/390 or in z/Architecture mode) has been added. This 14749 can be selected using -march=z900 and -mzarch respectively. 14750 * Instruction scheduling for the z900 and z990 processors now uses 14751 the DFA pipeline hazard recognizer. 14752 * GCC no longer generates code to maintain a stack backchain, 14753 previously used to generate stack backtraces for debugging 14754 purposes. As replacement that does not incur runtime overhead, 14755 DWARF-2 call frame information is provided by GCC; this is 14756 supported by GDB 6.1. The old behavior can be restored using the 14757 -mbackchain option. 14758 * The stack frame size of functions may now exceed 2 GB in 64-bit 14759 code. 14760 * A port for the 64-bit IBM TPF operating system has been added; the 14761 configuration is s390x-ibm-tpf. This configuration is supported as 14762 cross-compilation target only. 14763 * Various changes to improve the generated code have been 14764 implemented, including: 14765 + GCC now uses the MULTIPLY AND ADD and MULTIPLY AND SUBTRACT 14766 instructions to significantly speed up many floating-point 14767 applications. 14768 + GCC now uses the ADD LOGICAL WITH CARRY and SUBTRACT LOGICAL 14769 WITH BORROW instructions to speed up long long arithmetic. 14770 + GCC now uses the SEARCH STRING instruction to implement 14771 strlen(). 14772 + In many cases, function call overhead for 31-bit code has been 14773 reduced by placing the literal pool after the function code 14774 instead of after the function prolog. 14775 + Register 14 is no longer reserved in 64-bit code. 14776 + Handling of global register variables has been improved. 14777 14778 SPARC 14779 14780 * The option -mflat is deprecated. 14781 * Support for large (> 2GB) frames has been added to the 64-bit port. 14782 * Several [25]ABI bugs have been fixed. Unfortunately, these changes 14783 will break binary compatibility with earlier releases. 14784 * The default debugging format has been switched from STABS to 14785 DWARF-2 for 32-bit code on Solaris 7 and later. DWARF-2 is already 14786 the default debugging format for 64-bit code on Solaris. 14787 14788 SuperH 14789 14790 * Support for the SH2E processor has been added. Enabled at run time 14791 with the -m2e command line switch, or at configure time by 14792 specifying sh2e as the machine part of the target triple. 14793 14794 V850 14795 14796 * Support for the Mitsubishi V850E1 processor has been added. This is 14797 a variant of the V850E processor with some additional debugging 14798 instructions. 14799 14800 Xtensa 14801 14802 * Several ABI bugs have been fixed. Unfortunately, these changes 14803 break binary compatibility with earlier releases. 14804 + For big-endian processors, the padding of aggregate return 14805 values larger than a word has changed. If the size of an 14806 aggregate return value is not a multiple of 32 bits, previous 14807 versions of GCC inserted padding in the most-significant bytes 14808 of the first return value register. Aggregates larger than a 14809 word are now padded in the least-significant bytes of the last 14810 return value register used. Aggregates smaller than a word are 14811 still padded in the most-significant bytes. The return value 14812 padding has not changed for little-endian processors. 14813 + Function arguments with 16-byte alignment are now properly 14814 aligned. 14815 + The implementation of the va_list type has changed. A va_list 14816 value created by va_start from a previous release cannot be 14817 used with va_arg from this release, or vice versa. 14818 * More processor configuration options for Xtensa processors are 14819 supported: 14820 + the ABS instruction is now optional; 14821 + the ADDX* and SUBX* instructions are now optional; 14822 + an experimental CONST16 instruction can be used to synthesize 14823 constants instead of loading them from constant pools. 14824 These and other Xtensa processor configuration options can no 14825 longer be enabled or disabled by command-line options; the 14826 processor configuration must be specified by the xtensa-config.h 14827 header file when building GCC. Additionally, the 14828 -mno-serialize-volatile option is no longer supported. 14829 14830 Obsolete Systems 14831 14832 Support for a number of older systems has been declared obsolete in GCC 14833 3.4. Unless there is activity to revive them, the next release of GCC 14834 will have their sources permanently removed. 14835 14836 All configurations of the following processor architectures have been 14837 declared obsolete: 14838 * Mitsubishi D30V, d30v-* 14839 * AT&T DSP1600 and DSP1610, dsp16xx-* 14840 * Intel 80960, i960 14841 14842 Also, some individual systems have been obsoleted: 14843 * ARM Family 14844 + Support for generating code for operation in APCS/26 mode 14845 (-mapcs-26). 14846 * IBM ESA/390 14847 + "Bigfoot" port, i370-*. (The other port, s390-*, is actively 14848 maintained and supported.) 14849 * Intel 386 family 14850 + MOSS, i?86-moss-msdos and i?86-*-moss* 14851 + NCR 3000 running System V r.4, i?86-ncr-sysv4* 14852 + FreeBSD with a.out object format, i?86-*-freebsd*aout* and 14853 i?86-*-freebsd2* 14854 + GNU/Linux with a.out object format, i?86-linux*aout* 14855 + GNU/Linux with libc5, a.k.a. glibc1, i?86-linux*libc1* 14856 + Interix versions before Interix 3, i?86-*-interix 14857 + Mach microkernel, i?86-mach* 14858 + SCO UnixWare with UDK, i?86-*-udk* 14859 + Generic System V releases 1, 2, and 3, i?86-*-sysv[123]* 14860 + VSTa microkernel, i386-*-vsta 14861 * Motorola M68000 family 14862 + HPUX, m68k-hp-hpux* and m68000-hp-hpux* 14863 + NetBSD with a.out object format (before NetBSD 1.4), 14864 m68k-*-*-netbsd* except m68k-*-*-netbsdelf* 14865 + Generic System V r.4, m68k-*-sysv4* 14866 * VAX 14867 + Generic VAX, vax-*-* (This is generic VAX only; we have not 14868 obsoleted any VAX triples for specific operating systems.) 14869 14870 Documentation improvements 14871 14872 Other significant improvements 14873 14874 * The build system has undergone several significant cleanups. 14875 Subdirectories will only be configured if they are being built, and 14876 all subdirectory configures are run from the make command. The top 14877 level has been autoconfiscated. 14878 * Building GCC no longer writes to its source directory. This should 14879 help those wishing to share a read-only source directory over NFS 14880 or build from a CD. The exceptions to this feature are if you 14881 configure with either --enable-maintainer-mode or 14882 --enable-generated-files-in-srcdir. 14883 * The -W warning option has been renamed to -Wextra, which is more 14884 easily understood. The older spelling will be retained for 14885 backwards compatibility. 14886 * Substantial improvements in compile time have been made, 14887 particularly for non-optimizing compilations. 14888 __________________________________________________________________ 14889 14890 GCC 3.4.0 14891 14892 Bug Fixes 14893 14894 A vast number of bugs have been fixed in 3.4.0, too many to publish a 14895 complete list here. [26]Follow this link to query the Bugzilla database 14896 for the list of over 900 bugs fixed in 3.4.0. This is the list of all 14897 bugs marked as resolved and fixed in 3.4.0 that are not flagged as 3.4 14898 regressions. 14899 __________________________________________________________________ 14900 14901 GCC 3.4.1 14902 14903 Bug Fixes 14904 14905 This section lists the problem reports (PRs) from GCC's bug tracking 14906 system that are known to be fixed in the 3.4.1 release. This list might 14907 not be complete (that is, it is possible that some PRs that have been 14908 fixed are not listed here). 14909 14910 Bootstrap failures 14911 14912 * [27]10129 Ada bootstrap fails on PPC-Darwin - invalid assembler 14913 emitted - PIC related 14914 * [28]14576 [ARM] ICE in libiberty when building gcc-3.4 for arm-elf 14915 * [29]14760 A bug in configure.in prevents using both 14916 --program-suffix and --program-prefix 14917 * [30]14671 [hppa64] bootstrap fails: ICE in 14918 save_call_clobbered_regs, in caller_save.c 14919 * [31]15093 [alpha][Java] make bootstrap fails to configure libffi on 14920 Alpha 14921 * [32]15178 Solaris 9/x86 fails linking after stage 3 14922 14923 Multi-platform internal compiler errors (ICEs) 14924 14925 * [33]12753 (preprocessor) Memory corruption in preprocessor on bad 14926 input 14927 * [34]13985 ICE in gcc.c-torture/compile/930621-1.c 14928 * [35]14810 (c++) tree check failures with invalid code involving 14929 templates 14930 * [36]14883 (c++) ICE on invalid code, in cp_parser_lookup_name, in 14931 cp/parser.c 14932 * [37]15044 (c++) ICE on syntax error, template header 14933 * [38]15057 (c++) Compiling of conditional value throw constructs 14934 cause a segmentation violation 14935 * [39]15064 (c++) typeid of template parameter gives ICE 14936 * [40]15142 (c++) ICE when passing a string where a char* is expected 14937 in a throw statement 14938 * [41]15159 ICE in rtl_verify_flow_info_1 14939 * [42]15165 (c++) ICE in instantiate_template 14940 * [43]15193 Unary minus using pointer to V4SF vector causes 14941 -fforce-mem to exhaust all memory 14942 * [44]15209 (c++) Runs out of memory with packed structs 14943 * [45]15227 (c++) Trouble with invalid function definition 14944 * [46]15285 (c++) instantiate_type ICE when forming pointer to 14945 template function 14946 * [47]15299 (c++) ICE in resolve_overloaded_unification 14947 * [48]15329 (c++) ICE on constructor of member template 14948 * [49]15550 ICE in extract_insn, in recog.c 14949 * [50]15554 (c++) ICE in tsubst_copy, in cp/pt.c 14950 * [51]15640 (c++) ICE on invalid code in arg_assoc, in 14951 cp/name-lookup.c 14952 * [52]15666 [unit-at-a-time] Gcc abort on valid code 14953 * [53]15696 (c++) ICE with bad pointer-to-member code 14954 * [54]15701 (c++) ICE with friends and template template parameter 14955 * [55]15761 ICE in do_SUBST, in combine.c 14956 * [56]15829 (c++) ICE on Botan-1.3.13 due to -funroll-loops 14957 14958 Ada 14959 14960 * [57]14538 All RTEMS targets broken for gnat 14961 14962 C front end 14963 14964 * [58]12391 missing warning about assigning to an incomplete type 14965 * [59]14649 atan(1.0) should not be a constant expression 14966 * [60]15004 [unit-at-a-time] no warning for unused paramater in 14967 static function 14968 * [61]15749 --pedantic-errors behaves differently from --pedantic 14969 with C-compiler on GNU/Linux 14970 14971 C++ compiler and library 14972 14973 * [62]10646 non-const reference is incorrectly matched in a "const T" 14974 partial specialization 14975 * [63]12077 wcin.rdbuf()->in_avail() return value too high 14976 * [64]13598 enc_filebuf doesn't work 14977 * [65]14211 const_cast returns lvalue but should be rvalue 14978 * [66]14220 num_put::do_put() undesired float/double behavior 14979 * [67]14245 problem with user-defined allocators in std::basic_string 14980 * [68]14340 libstdc++ Debug mode: failure to convert iterator to 14981 const_iterator 14982 * [69]14600 __gnu_cxx::stdio_sync_filebuf should expose internal 14983 FILE* 14984 * [70]14668 no warning anymore for reevaluation of declaration 14985 * [71]14775 LFS (large file support) tests missing 14986 * [72]14821 Duplicate namespace alias declaration should not conflict 14987 * [73]14930 Friend declaration ignored 14988 * [74]14932 cannot use offsetof to get offsets of array elements in 14989 g++ 3.4.0 14990 * [75]14950 [non unit-at-a-time] always_inline does not mix with 14991 templates and -O0 14992 * [76]14962 g++ ignores #pragma redefine_extname 14993 * [77]14975 Segfault on low-level write error during imbue 14994 * [78]15002 Linewise stream input is unusably slow (std::string slow) 14995 * [79]15025 compiler accepts redeclaration of template as 14996 non-template 14997 * [80]15046 [arm] Math functions misdetected by cross configuration 14998 * [81]15069 a bit test on a variable of enum type is miscompiled 14999 * [82]15074 g++ -lsupc++ still links against libstdc++ 15000 * [83]15083 spurious "statement has no effect" warning 15001 * [84]15096 parse error with templates and pointer to const member 15002 * [85]15287 combination of operator[] and operator .* fails in 15003 templates 15004 * [86]15317 __attribute__ unused in first parameter of constructor 15005 gives error 15006 * [87]15337 sizeof on incomplete type diagnostic 15007 * [88]15361 bitset<>::_Find_next fails 15008 * [89]15412 _GLIBCXX_ symbols symbols defined and used in different 15009 namespaces 15010 * [90]15427 valid code results in incomplete type error 15011 * [91]15471 Incorrect member pointer offsets in anonymous 15012 structs/unions 15013 * [92]15503 nested template problem 15014 * [93]15507 compiler hangs while laying out union 15015 * [94]15542 operator & and template definitions 15016 * [95]15565 SLES9: leading + sign for unsigned int with showpos 15017 * [96]15625 friend defined inside a template fails to find static 15018 function 15019 * [97]15629 Function templates, overloads, and friend name injection 15020 * [98]15742 'noreturn' attribute ignored in method of template 15021 functions. 15022 * [99]15775 Allocator::pointer consistently ignored 15023 * [100]15821 Duplicate namespace alias within namespace rejected 15024 * [101]15862 'enum yn' fails (confict with undeclared builtin) 15025 * [102]15875 rejects pointer to member in template 15026 * [103]15877 valid code using templates and anonymous enums is 15027 rejected 15028 * [104]15947 Puzzling error message for wrong destructor declaration 15029 in template class 15030 * [105]16020 cannot copy __gnu_debug::bitset 15031 * [106]16154 input iterator concept too restrictive 15032 * [107]16174 deducing top-level consts 15033 15034 Java 15035 15036 * [108]14315 Java compiler is not parallel make safe 15037 15038 Fortran 15039 15040 * [109]15151 [g77] incorrect logical i/o in 64-bit mode 15041 15042 Objective-C 15043 15044 * [110]7993 private variables cannot be shadowed in subclasses 15045 15046 Optimization bugs 15047 15048 * [111]15228 useless copies of floating point operands 15049 * [112]15345 [non-unit-at-a-time] unreferenced nested inline 15050 functions not optimized away 15051 * [113]15945 Incorrect floating point optimization 15052 * [114]15526 ftrapv aborts on 0 * (-1) 15053 * [115]14690 Miscompiled POOMA tests 15054 * [116]15112 GCC generates code to write to unchanging memory 15055 15056 Preprocessor 15057 15058 * [117]15067 Minor glitch in the source of cpp 15059 15060 Main driver program bugs 15061 15062 * [118]1963 collect2 interprets -oldstyle_liblookup as -o 15063 ldstyle_liblookup 15064 15065 x86-specific (Intel/AMD) 15066 15067 * [119]15717 Error: can't resolve `L0' {*ABS* section} - `xx' {*UND* 15068 section} 15069 15070 HPPA-specific 15071 15072 * [120]14782 GCC produces an unaligned data access at -O2 15073 * [121]14828 FAIL: gcc.c-torture/execute/20030408-1.c execution, -O2 15074 * [122]15202 ICE in reload_cse_simplify_operands, in postreload.c 15075 15076 IA64-specific 15077 15078 * [123]14610 __float80 constants incorrectly emitted 15079 * [124]14813 init_array sections are initialized in the wrong order 15080 * [125]14857 GCC segfault on duplicated asm statement 15081 * [126]15598 Gcc 3.4 ICE on valid code 15082 * [127]15653 Gcc 3.4 ICE on valid code 15083 15084 MIPS-specific 15085 15086 * [128]15189 wrong filling of delay slot with -march=mips1 -G0 15087 -mno-split-addresses -mno-explicit-relocs 15088 * [129]15331 Assembler error building gnatlib on IRIX 6.5 with GNU as 15089 2.14.91 15090 * [130]16144 Bogus reference to __divdf3 when -O1 15091 * [131]16176 Miscompilation of unaligned data in MIPS backend 15092 15093 PowerPC-specific 15094 15095 * [132]11591 ICE in gcc.dg/altivec-5.c 15096 * [133]12028 powerpc-eabispe produces bad sCOND operation 15097 * [134]14478 rs6000 geu/ltu patterns generate incorrect code 15098 * [135]14567 long double and va_arg complex args 15099 * [136]14715 Altivec stack layout may overlap gpr save with stack 15100 temps 15101 * [137]14902 (libstdc++) Stream checking functions fail when -pthread 15102 option is used. 15103 * [138]14924 Compiler ICE on valid code 15104 * [139]14960 -maltivec affects vector return with -mabi=no-altivec 15105 * [140]15106 vector varargs failure passing from altivec to 15106 non-altivec code for -m32 15107 * [141]16026 ICE in function.c:4804, assign_parms, when -mpowerpc64 & 15108 half-word operation 15109 * [142]15191 -maltivec -mabi=no-altivec results in mis-aligned lvx 15110 and stvx 15111 * [143]15662 Segmentation fault when an exception is thrown - even if 15112 try and catch are specified 15113 15114 s390-specific 15115 15116 * [144]15054 Bad code due to overlapping stack temporaries 15117 15118 SPARC-specific 15119 15120 * [145]15783 ICE with union assignment in 64-bit mode 15121 * [146]15626 GCC 3.4 emits "ld: warning: relocation error: 15122 R_SPARC_UA32" 15123 15124 x86-64-specific 15125 15126 * [147]14326 boehm-gc hardcodes to 3DNow! prefetch for x86_64 15127 * [148]14723 Backported -march=nocona from mainline 15128 * [149]15290 __float128 failed to pass to function properly 15129 15130 Cygwin/Mingw32-specific 15131 15132 * [150]15250 Option -mms-bitfields support on GCC 3.4 is not 15133 conformant to MS layout 15134 * [151]15551 -mtune=pentium4 -O2 with sjlj EH breaks stack probe 15135 worker on windows32 targets 15136 15137 Bugs specific to embedded processors 15138 15139 * [152]8309 [m68k] -m5200 produces erroneous SImode set of short 15140 varaible on stack 15141 * [153]13250 [SH] Gcc code for rotation clobbers the register, but 15142 gcc continues to use the register as if it was not clobbered 15143 * [154]13803 [coldfire] movqi operand constraints too restrictivefor 15144 TARGET_COLDFIRE 15145 * [155]14093 [SH] ICE for code when using -mhitachi option in SH 15146 * [156]14457 [m6811hc] ICE with simple c++ source 15147 * [157]14542 [m6811hc] ICE on simple source 15148 * [158]15100 [SH] cc1plus got hang-up on 15149 libstdc++-v3/testsuite/abi_check.cc 15150 * [159]15296 [CRIS] Delayed branch scheduling causing invalid code on 15151 cris-* 15152 * [160]15396 [SH] ICE with -O2 -fPIC 15153 * [161]15782 [coldfire] m68k_output_mi_thunk emits wrong code for 15154 ColdFire 15155 15156 Testsuite problems (compiler not affected) 15157 15158 * [162]11610 libstdc++ testcases 27_io/* don't work properly remotely 15159 * [163]15488 (libstdc++) possibly insufficient file permissions for 15160 executing test suite 15161 * [164]15489 (libstdc++) testsuite_files determined incorrectly 15162 15163 Documentation bugs 15164 15165 * [165]13928 (libstdc++) no whatis info in some man pages generated 15166 by doxygen 15167 * [166]14150 Ada documentation out of date 15168 * [167]14949 (c++) Need to document method visibility changes 15169 * [168]15123 libstdc++-doc: Allocators.3 manpage is empty 15170 __________________________________________________________________ 15171 15172 GCC 3.4.2 15173 15174 Bug Fixes 15175 15176 This section lists the problem reports (PRs) from GCC's bug tracking 15177 system that are known to be fixed in the 3.4.2 release. This list might 15178 not be complete (that is, it is possible that some PRs that have been 15179 fixed are not listed here). 15180 15181 Bootstrap failures and issues 15182 15183 * [169]16469 [mips-sgi-irix5.3] bootstrap fails in 15184 libstdc++-v3/testsuite 15185 * [170]16344 [hppa-linux-gnu] libstdc++'s PCH built by 15186 profiledbootstrap does not work with the built compiler 15187 * [171]16842 [Solaris/x86] mkheaders can not find mkheaders.conf 15188 15189 Multi-platform internal compiler errors (ICEs) 15190 15191 * [172]12608 (c++) ICE: expected class 't', have 'x' (error_mark) in 15192 cp_parser_class_specifier, in cp/parser.c 15193 * [173]14492 ICE in loc_descriptor_from_tree, in dwarf2out.c 15194 * [174]15461 (c++) ICE due to NRV and inlining 15195 * [175]15890 (c++) ICE in c_expand_expr, in c-common.c 15196 * [176]16180 ICE: segmentation fault in RTL optimization 15197 * [177]16224 (c++) ICE in write_unscoped_name (template/namespace) 15198 * [178]16408 ICE: in delete_insn, in cfgrtl.c 15199 * [179]16529 (c++) ICE for: namespace-alias shall not be declared as 15200 the name of any other entity 15201 * [180]16698 (c++) ICE with exceptions and declaration of __cxa_throw 15202 * [181]16706 (c++) ICE in finish_member_declaration, in 15203 cp/semantics.c 15204 * [182]16810 (c++) Legal C++ program with cast gives ICE in 15205 build_ptrmemfunc 15206 * [183]16851 (c++) ICE when throwing a comma expression 15207 * [184]16870 (c++) Boost.Spirit causes ICE in tsubst, in cp/pt.c 15208 * [185]16904 (c++) ICE in finish_class_member_access_expr, in 15209 cp/typeck.c 15210 * [186]16905 (c++) ICE (segfault) with exceptions 15211 * [187]16964 (c++) ICE in cp_parser_class_specifier due to 15212 redefinition 15213 * [188]17068 (c++) ICE: tree check: expected class 'd', have 'x' 15214 (identifier_node) in dependent_template_p, in cp/pt.c 15215 15216 Preprocessor bugs 15217 15218 * [189]16366 Preprocessor option -remap causes memory corruption 15219 15220 Optimization 15221 15222 * [190]15345 unreferenced nested inline functions not optimized away 15223 * [191]16590 Incorrect execution when compiling with -O2 15224 * [192]16693 Bitwise AND is lost when used within a cast to an enum 15225 of the same precision 15226 * [193]17078 Jump into if(0) substatement fails 15227 15228 Problems in generated debug information 15229 15230 * [194]13956 incorrect stabs for nested local variables 15231 15232 C front end bugs 15233 15234 * [195]16684 GCC should not warn about redundant redeclarations of 15235 built-ins 15236 15237 C++ compiler and library 15238 15239 * [196]12658 Thread safety problems in locale::global() and 15240 locale::locale() 15241 * [197]13092 g++ accepts invalid pointer-to-member conversion 15242 * [198]15320 Excessive memory consumption 15243 * [199]16246 Incorrect template argument deduction 15244 * [200]16273 Memory exhausted when using nested classes and virtual 15245 functions 15246 * [201]16401 ostringstream in gcc 3.4.x very slow for big data 15247 * [202]16411 undefined reference to 15248 __gnu_cxx::stdio_sync_filebuf<char, std::char_traits<char> 15249 >::file() 15250 * [203]16489 G++ incorrectly rejects use of a null constant integral 15251 expression as a null constant pointer 15252 * [204]16618 offsetof fails with constant member 15253 * [205]16637 syntax error reported for valid input code 15254 * [206]16717 __attribute__((constructor)) broken in C++ 15255 * [207]16813 compiler error in DEBUG version of range insertion 15256 std::map::insert 15257 * [208]16853 pointer-to-member initialization from incompatible one 15258 accepted 15259 * [209]16889 ambiguity is not detected 15260 * [210]16959 Segmentation fault in ios_base::sync_with_stdio 15261 15262 Java compiler and library 15263 15264 * [211]7587 direct threaded interpreter not thread-safe 15265 * [212]16473 ServerSocket accept() leaks file descriptors 15266 * [213]16478 Hash synchronization deadlock with finalizers 15267 15268 Alpha-specific 15269 15270 * [214]10695 ICE in dwarf2out_frame_debug_expr, in dwarf2out.c 15271 * [215]16974 could not split insn (ice in final_scan_insn, in 15272 final.c) 15273 15274 x86-specific 15275 15276 * [216]16298 ICE in output_operand 15277 * [217]17113 ICE with SSE2 intrinsics 15278 15279 x86-64 specific 15280 15281 * [218]14697 libstdc++ couldn't find 32bit libgcc_s 15282 15283 MIPS-specific 15284 15285 * [219]15869 [mips64] No NOP after LW (with -mips1 -O0) 15286 * [220]16325 [mips64] value profiling clobbers gp on mips 15287 * [221]16357 [mipsisa64-elf] ICE copying 7 bytes between extern 15288 char[]s 15289 * [222]16380 [mips64] Use of uninitialised register after dbra 15290 conversion 15291 * [223]16407 [mips64] Unaligned access to local variables 15292 * [224]16643 [mips64] verify_local_live_at_start ICE after 15293 crossjumping & cfgcleanup 15294 15295 ARM-specific 15296 15297 * [225]15927 THUMB -O2: strength-reduced iteration variable ends up 15298 off by 1 15299 * [226]15948 THUMB: ICE with non-commutative cbranch 15300 * [227]17019 THUMB: bad switch statement in md code for 15301 addsi3_cbranch_scratch 15302 15303 IA64-specific 15304 15305 * [228]16130 ICE on valid code: in bundling, in config/ia64/ia64.c 15306 (-mtune=merced) 15307 * [229]16142 ICE on valid code: in bundling, in config/ia64/ia64.c 15308 (-mtune=itanium) 15309 * [230]16278 Gcc failed to build Linux kernel with -mtune=merced 15310 * [231]16414 ICE on valid code: typo in comparison of asm_noperands 15311 result 15312 * [232]16445 ICE on valid code: don't count ignored insns 15313 * [233]16490 ICE (segfault) while compiling with -fprofile-use 15314 * [234]16683 ia64 does not honor SUBTARGET_EXTRA_SPECS 15315 15316 PowerPC-specific 15317 15318 * [235]16195 (ppc64): Miscompilation of GCC 3.3.x by 3.4.x 15319 * [236]16239 ICE on ppc64 (mozilla 1.7 compile, -O1 -fno-exceptions 15320 issue) 15321 15322 SPARC-specific 15323 15324 * [237]16199 ICE while compiling apache 2.0.49 15325 * [238]16416 -m64 doesn't imply -mcpu=v9 anymore 15326 * [239]16430 ICE when returning non-C aggregates larger than 16 bytes 15327 15328 Bugs specific to embedded processors 15329 15330 * [240]16379 [m32r] can't output large model function call of memcpy 15331 * [241]17093 [m32r] ICE with -msdata=use -O0 15332 * [242]17119 [m32r] ICE at switch case 0x8000 15333 15334 DJGPP-specific 15335 15336 * [243]15928 libstdc++ in 3.4.x doesn't cross-compile for djgpp 15337 15338 Alpha Tru64-specific 15339 15340 * [244]16210 libstdc++ gratuitously omits "long long" I/O 15341 15342 Testsuite, documentation issues (compiler is not affected): 15343 15344 * [245]15488 (libstdc++) possibly insufficient file permissions for 15345 executing test suite 15346 * [246]16250 ada/doctools runs makeinfo even in release tarball 15347 __________________________________________________________________ 15348 15349 GCC 3.4.3 15350 15351 This is the [247]list of problem reports (PRs) from GCC's bug tracking 15352 system that are known to be fixed in the 3.4.3 release. This list might 15353 not be complete (that is, it is possible that some PRs that have been 15354 fixed are not listed here). 15355 15356 Bootstrap failures 15357 15358 * [248]17369 [ia64] Bootstrap failure with binutils-2.15.90.0.1.1 15359 * [249]17850 [arm-elf] bootstrap failure - libstdc++ uses strtold 15360 when undeclared 15361 15362 Internal compiler errors (ICEs) affecting multiple platforms 15363 15364 * [250]13948 (java) GCJ segmentation fault while compiling GL4Java 15365 .class files 15366 * [251]14492 ICE in loc_descriptor_from_tree, in dwarf2out.c 15367 * [252]16301 (c++) ICE when "strong" attribute is attached to a using 15368 directive 15369 * [253]16566 ICE with flexible arrays 15370 * [254]17023 ICE with nested functions in parameter declaration 15371 * [255]17027 ICE with noreturn function in loop at -O2 15372 * [256]17524 ICE in grokdeclarator, in cp/decl.c 15373 * [257]17826 (c++) ICE in cp_tree_equal 15374 15375 C and optimization bugs 15376 15377 * [258]15526 -ftrapv aborts on 0 * (-1) 15378 * [259]16999 #ident stopped working 15379 * [260]17503 quadratic behaviour in invalid_mode_change_p 15380 * [261]17581 Long long arithmetic fails inside a switch/case 15381 statement when compiled with -O2 15382 * [262]18129 -fwritable-strings doesn't work 15383 15384 C++ compiler and library bugs 15385 15386 * [263]10975 incorrect initial ostringstream::tellp() 15387 * [264]11722 Unbuffered filebuf::sgetn is slow 15388 * [265]14534 Unrecognizing static function as a template parameter 15389 when its return value is also templated 15390 * [266]15172 Copy constructor optimization in aggregate 15391 initialization 15392 * [267]15786 Bad error message for frequently occuring error. 15393 * [268]16162 Rejects valid member-template-definition 15394 * [269]16612 empty basic_strings can't live in shared memory 15395 * [270]16715 std::basic_iostream is instantiated when used, even 15396 though instantiations are already contained in libstdc++ 15397 * [271]16848 code in /ext/demangle.h appears broken 15398 * [272]17132 GCC fails to eliminate function template specialization 15399 when argument deduction fails 15400 * [273]17259 One more _S_leaf incorrectly qualified with _RopeRep:: 15401 in ropeimpl.h 15402 * [274]17327 use of `enumeral_type' in template type unification 15403 * [275]17393 "unused variable '._0'" warning with -Wall 15404 * [276]17501 Confusion with member templates 15405 * [277]17537 g++ not passing -lstdc++ to linker when all command line 15406 arguments are libraries 15407 * [278]17585 usage of unqualified name of static member from within 15408 class not allowed 15409 * [279]17821 Poor diagnostic for using "." instead of "->" 15410 * [280]17829 wrong error: call of overloaded function is ambiguous 15411 * [281]17851 Misleading diagnostic for invalid function declarations 15412 with undeclared types 15413 * [282]17976 Destructor is called twice 15414 * [283]18020 rejects valid definition of enum value in template 15415 * [284]18093 bogus conflict in namespace aliasing 15416 * [285]18140 C++ parser bug when using >> in templates 15417 15418 Fortran 15419 15420 * [286]17541 data statements with double precision constants fail 15421 15422 x86-specific 15423 15424 * [287]17853 -O2 ICE for MMX testcase 15425 15426 SPARC-specific 15427 15428 * [288]17245 ICE compiling gsl-1.5 statistics/lag1.c 15429 15430 Darwin-specific 15431 15432 * [289]17167 FATAL:Symbol L_foo$stub already defined. 15433 15434 AIX-specific 15435 15436 * [290]17277 could not catch an exception when specified -maix64 15437 15438 Solaris-specific 15439 15440 * [291]17505 <cmath> calls acosf(), ceilf(), and other functions 15441 missing from system libraries 15442 15443 HP/UX specific: 15444 15445 * [292]17684 /usr/ccs/bin/ld: Can't create libgcc_s.sl 15446 15447 ARM-specific 15448 15449 * [293]17384 ICE with mode attribute on structures 15450 15451 MIPS-specific 15452 15453 * [294]17770 No NOP after LWL with -mips1 15454 15455 Other embedded target specific 15456 15457 * [295]11476 [arc-elf] gcc ICE on newlib's vfprintf.c 15458 * [296]14064 [avr-elf] -fdata-sections triggers ICE 15459 * [297]14678 [m68hc11-elf] gcc ICE 15460 * [298]15583 [powerpc-rtems] powerpc-rtems lacks __USE_INIT_FINI__ 15461 * [299]15790 [i686-coff] Alignment error building gcc with i686-coff 15462 target 15463 * [300]15886 [SH] Miscompilation with -O2 -fPIC 15464 * [301]16884 [avr-elf] [fweb related] bug while initializing 15465 variables 15466 15467 Bugs relating to debugger support 15468 15469 * [302]13841 missing debug info for _Complex function arguments 15470 * [303]15860 [big-endian targets] No DW_AT_location debug info is 15471 emitted for formal arguments to a function that uses "register" 15472 qualifiers 15473 15474 Testsuite issues (compiler not affected) 15475 15476 * [304]17465 Testsuite in libffi overrides LD_LIBRARY_PATH 15477 * [305]17469 Testsuite in libstdc++ overrides LD_LIBRARY_PATH 15478 * [306]18138 [mips-sgi-irix6.5] libgcc_s.so.1 not found by 64-bit 15479 testsuite 15480 15481 Documentation 15482 15483 * [307]15498 typo in gcc manual: non-existing locale example en_UK, 15484 should be en_GB 15485 * [308]15747 [mips-sgi-irix5.3] /bin/sh hangs during bootstrap: 15486 document broken shell 15487 * [309]16406 USE_LD_AS_NEEDED undocumented 15488 __________________________________________________________________ 15489 15490 GCC 3.4.4 15491 15492 This is the [310]list of problem reports (PRs) from GCC's bug tracking 15493 system that are known to be fixed in the 3.4.4 release. This list might 15494 not be complete (that is, it is possible that some PRs that have been 15495 fixed are not listed here). 15496 __________________________________________________________________ 15497 15498 GCC 3.4.5 15499 15500 This is the [311]list of problem reports (PRs) from GCC's bug tracking 15501 system that are known to be fixed in the 3.4.5 release. This list might 15502 not be complete (that is, it is possible that some PRs that have been 15503 fixed are not listed here). 15504 15505 Bootstrap issues 15506 15507 * [312]24688 sco_math fixincl breaks math.h 15508 15509 C compiler bugs 15510 15511 * [313]17188 struct Foo { } redefinition 15512 * [314]20187 wrong code for ((unsigned char)(unsigned long 15513 long)((a?a:1)&(a*b)))?0:1) 15514 * [315]21873 infinite warning loop on bad array initializer 15515 * [316]21899 enum definition accepts values to be overriden 15516 * [317]22061 ICE in find_function_data, in function.c 15517 * [318]22308 Failure to diagnose violation of constraint 6.516p2 15518 * [319]22458 ICE on missing brace 15519 * [320]22589 ICE casting to long long 15520 * [321]24101 Segfault with preprocessed source 15521 15522 C++ compiler and library bugs 15523 15524 * [322]10611 operations on vector mode not recognized in C++ 15525 * [323]13377 unexpected behavior of namespace usage directive 15526 * [324]16002 Strange error message with new parser 15527 * [325]17413 local classes as template argument 15528 * [326]17609 spurious error message after using keyword 15529 * [327]17618 ICE in cp_convert_to_pointer, in cp/cvt.c 15530 * [328]18124 ICE with invalid template template parameter 15531 * [329]18155 typedef in template declaration not rejected 15532 * [330]18177 ICE with const_cast for undeclared variable 15533 * [331]18368 C++ error message regression 15534 * [332]16378 ICE when returning a copy of a packed member 15535 * [333]18466 int ::i; accepted 15536 * [334]18512 ICE on invalid usage of template base class 15537 * [335]18454 ICE when returning undefined type 15538 * [336]18738 typename not allowed with non-dependent qualified name 15539 * [337]18803 rejects access to operator() in template 15540 * [338]19004 ICE in uses_template_parms, in cp/pt.c 15541 * [339]19208 Spurious error about variably modified type 15542 * [340]18253 bad error message / ICE for invalid template parameter 15543 * [341]19608 ICE after friend function definition in local class 15544 * [342]19884 ICE on explicit instantiation of a non-template 15545 constructor 15546 * [343]20153 ICE when C++ template function contains anonymous union 15547 * [344]20563 Infinite loop in diagnostic (and ice after error 15548 message) 15549 * [345]20789 ICE with incomplete type in template 15550 * [346]21336 Internal compiler error when using custom new operators 15551 * [347]21768 ICE in error message due to violation of coding 15552 conventions 15553 * [348]21853 constness of pointer to data member ignored 15554 * [349]21903 Default argument of template function causes a 15555 compile-time error 15556 * [350]21983 multiple diagnostics 15557 * [351]21987 New testsuite failure 15558 g++.dg/warn/conversion-function-1.C 15559 * [352]22153 ICE on invalid template specialization 15560 * [353]22172 Internal compiler error, seg fault. 15561 * [354]21286 filebuf::xsgetn vs pipes 15562 * [355]22233 ICE with wrong number of template parameters 15563 * [356]22508 ICE after invalid operator new 15564 * [357]22545 ICE with pointer to class member & user defined 15565 conversion operator 15566 * [358]23528 Wrong default allocator in ext/hash_map 15567 * [359]23550 char_traits requirements/1.cc test bad math 15568 * [360]23586 Bad diagnostic for invalid namespace-name 15569 * [361]23624 ICE in invert_truthvalue, in fold-const.c 15570 * [362]23639 Bad error message: not a member of '<declaration error>' 15571 * [363]23797 ICE on typename outside template 15572 * [364]23965 Bogus error message: no matching function for call to 15573 'foo(<type error>)' 15574 * [365]24052 &#`label_decl' not supported by dump_expr#<expression 15575 error> 15576 * [366]24580 virtual base class cause exception not to be caught 15577 15578 Problems in generated debug information 15579 15580 * [367]24267 Bad DWARF for altivec vectors 15581 15582 Optimizations issues 15583 15584 * [368]17810 ICE in verify_local_live_at_start 15585 * [369]17860 Wrong generated code for loop with varying bound 15586 * [370]21709 ICE on compile-time complex NaN 15587 * [371]21964 broken tail call at -O2 or more 15588 * [372]22167 Strange optimization bug when using -Os 15589 * [373]22619 Compilation failure for real_const_1.f and 15590 real_const_2.f90 15591 * [374]23241 Invalid code generated for comparison of uchar to 255 15592 * [375]23478 Miscompilation due to reloading of a var that is also 15593 used in EH pad 15594 * [376]24470 segmentation fault in cc1plus when compiling with -O 15595 * [377]24950 ICE in operand_subword_force 15596 15597 Precompiled headers problems 15598 15599 * [378]14400 Cannot compile qt-x11-free-3.3.0 15600 * [379]14940 PCH largefile test fails on various platforms 15601 15602 Preprocessor bugs 15603 15604 * [380]20239 ICE on empty preprocessed input 15605 * [381]15220 "gcc -E -MM -MG" reports missing system headers in 15606 source directory 15607 15608 Testsuite issues 15609 15610 * [382]19275 gcc.dg/20020919-1.c fails with -fpic/-fPIC on 15611 i686-pc-linux-gnu 15612 15613 Alpha specific 15614 15615 * [383]21888 bootstrap failure with linker relaxation enabled 15616 15617 ARM specific 15618 15619 * [384]15342 [arm-linux]: ICE in verify_local_live_at_start 15620 * [385]23985 Memory aliasing information incorrect in inlined memcpy 15621 15622 ColdFile specific 15623 15624 * [386]16719 Illegal move of byte into address register causes 15625 compiler to ICE 15626 15627 HPPA specific 15628 15629 * [387]21723 ICE while building libgfortran 15630 * [388]21841 -mhp-ld/-mgnu-ld documentation 15631 15632 IA-64 specific 15633 15634 * [389]23644 IA-64 hardware models and configuration options 15635 documentation error 15636 * [390]24718 Shared libgcc not used for linking by default 15637 15638 M68000 specific 15639 15640 * [391]18421 ICE in reload_cse_simplify_operands, in postreload.c 15641 15642 MIPS specific 15643 15644 * [392]20621 ICE in change_address_1, in emit-rtl.c 15645 15646 PowerPC and PowerPC64 specific 15647 15648 * [393]18583 error on valid code: const 15649 __attribute__((altivec(vector__))) doesn't work in arrays 15650 * [394]20191 ICE in reload_cse_simplify_operands 15651 * [395]22083 AIX: TARGET_C99_FUNCTIONS is wrongly defined 15652 * [396]23070 CALL_V4_CLEAR_FP_ARGS flag not properly set 15653 * [397]23404 gij trashes args of functions with more than 8 fp args 15654 * [398]23539 C & C++ compiler generating misaligned references 15655 regardless of compiler flags 15656 * [399]24102 floatdisf2_internal2 broken 15657 * [400]24465 -mminimal-toc miscompilation of __thread vars 15658 15659 Solaris specific 15660 15661 * [401]19933 Problem with define of HUGE_VAL in math_c99 15662 * [402]21889 Native Solaris assembler cannot grok DTP-relative debug 15663 symbols 15664 15665 SPARC specific 15666 15667 * [403]19300 PCH failures on sparc-linux 15668 * [404]20301 Assembler labels have a leading "-" 15669 * [405]20673 C PCH testsuite assembly comparison failure 15670 15671 x86 and x86_64 specific 15672 15673 * [406]18582 ICE with arrays of type V2DF 15674 * [407]19340 Compilation SEGFAULTs with -O1 -fschedule-insns2 15675 -fsched2-use-traces 15676 * [408]21716 ICE in reg-stack.c's swap_rtx_condition 15677 * [409]24315 amd64 fails -fpeephole2 15678 __________________________________________________________________ 15679 15680 GCC 3.4.6 15681 15682 This is the [410]list of problem reports (PRs) from GCC's bug tracking 15683 system that are known to be fixed in the 3.4.6 release. This list might 15684 not be complete (that is, it is possible that some PRs that have been 15685 fixed are not listed here). 15686 15687 15688 For questions related to the use of GCC, please consult these web 15689 pages and the [411]GCC manuals. If that fails, the 15690 [412]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 15691 web pages and the development of GCC are welcome on our developer 15692 list at [413]gcc (a] gcc.gnu.org. All of [414]our lists have public 15693 archives. 15694 15695 Copyright (C) [415]Free Software Foundation, Inc. Verbatim copying and 15696 distribution of this entire article is permitted in any medium, 15697 provided this notice is preserved. 15698 15699 These pages are [416]maintained by the GCC team. Last modified 15700 2023-01-27. 15701 15702 References 15703 15704 1. http://gcc.gnu.org/gcc-3.4/changes.html#3.4.6 15705 2. http://gcc.gnu.org/gcc-3.4/changes.html#cplusplus 15706 3. http://gcc.gnu.org/gcc-3.3/changes.html#obsolete_systems 15707 4. http://gcc.gnu.org/gcc-3.4/changes.html#obsolete_systems 15708 5. http://gcc.gnu.org/gcc-3.4/mips-abi.html 15709 6. http://gcc.gnu.org/gcc-3.4/sparc-abi.html 15710 7. https://www.boost.org/ 15711 8. https://gcc.gnu.org/PR11953 15712 9. https://gcc.gnu.org/PR8361 15713 10. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gcc/Other-Builtins.html#Other%20Builtins 15714 11. https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_closed.html#209 15715 12. http://gcc.gnu.org/bugs/#cxx_rvalbind 15716 13. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gcc/Objective-C-Dialect-Options.html 15717 14. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gcc/Objective-C-Dialect-Options.html 15718 15. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gcc/Objective-C-Dialect-Options.html 15719 16. http://www.gnu.org/software/classpath/ 15720 17. https://www.eclipse.org/ 15721 18. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/g77/News.html 15722 19. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gcc/Alpha-Built-in-Functions.html 15723 20. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gccint/Processor-pipeline-description.html 15724 21. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gccint/Comparison-of-the-two-descriptions.html 15725 22. https://gcc.gnu.org/onlinedocs/gcc-3.4.3/gccint/Processor-pipeline-description.html 15726 23. http://gcc.gnu.org/gcc-3.4/mips-abi.html 15727 24. http://gcc.gnu.org/gcc-3.4/powerpc-abi.html 15728 25. http://gcc.gnu.org/gcc-3.4/sparc-abi.html 15729 26. https://gcc.gnu.org/bugzilla/buglist.cgi?short_desc_type=notregexp&short_desc=%5C%5B3%5C.4.*%5BRr%5Degression&target_milestone=3.4.0&bug_status=RESOLVED&resolution=FIXED 15730 27. https://gcc.gnu.org/PR10129 15731 28. https://gcc.gnu.org/PR14576 15732 29. https://gcc.gnu.org/PR14760 15733 30. https://gcc.gnu.org/PR14671 15734 31. https://gcc.gnu.org/PR15093 15735 32. https://gcc.gnu.org/PR15178 15736 33. https://gcc.gnu.org/PR12753 15737 34. https://gcc.gnu.org/PR13985 15738 35. https://gcc.gnu.org/PR14810 15739 36. https://gcc.gnu.org/PR14883 15740 37. https://gcc.gnu.org/PR15044 15741 38. https://gcc.gnu.org/PR15057 15742 39. https://gcc.gnu.org/PR15064 15743 40. https://gcc.gnu.org/PR15142 15744 41. https://gcc.gnu.org/PR15159 15745 42. https://gcc.gnu.org/PR15165 15746 43. https://gcc.gnu.org/PR15193 15747 44. https://gcc.gnu.org/PR15209 15748 45. https://gcc.gnu.org/PR15227 15749 46. https://gcc.gnu.org/PR15285 15750 47. https://gcc.gnu.org/PR15299 15751 48. https://gcc.gnu.org/PR15329 15752 49. https://gcc.gnu.org/PR15550 15753 50. https://gcc.gnu.org/PR15554 15754 51. https://gcc.gnu.org/PR15640 15755 52. https://gcc.gnu.org/PR15666 15756 53. https://gcc.gnu.org/PR15696 15757 54. https://gcc.gnu.org/PR15701 15758 55. https://gcc.gnu.org/PR15761 15759 56. https://gcc.gnu.org/PR15829 15760 57. https://gcc.gnu.org/PR14538 15761 58. https://gcc.gnu.org/PR12391 15762 59. https://gcc.gnu.org/PR14649 15763 60. https://gcc.gnu.org/PR15004 15764 61. https://gcc.gnu.org/PR15749 15765 62. https://gcc.gnu.org/PR10646 15766 63. https://gcc.gnu.org/PR12077 15767 64. https://gcc.gnu.org/PR13598 15768 65. https://gcc.gnu.org/PR14211 15769 66. https://gcc.gnu.org/PR14220 15770 67. https://gcc.gnu.org/PR14245 15771 68. https://gcc.gnu.org/PR14340 15772 69. https://gcc.gnu.org/PR14600 15773 70. https://gcc.gnu.org/PR14668 15774 71. https://gcc.gnu.org/PR14775 15775 72. https://gcc.gnu.org/PR14821 15776 73. https://gcc.gnu.org/PR14930 15777 74. https://gcc.gnu.org/PR14932 15778 75. https://gcc.gnu.org/PR14950 15779 76. https://gcc.gnu.org/PR14962 15780 77. https://gcc.gnu.org/PR14975 15781 78. https://gcc.gnu.org/PR15002 15782 79. https://gcc.gnu.org/PR15025 15783 80. https://gcc.gnu.org/PR15046 15784 81. https://gcc.gnu.org/PR15069 15785 82. https://gcc.gnu.org/PR15074 15786 83. https://gcc.gnu.org/PR15083 15787 84. https://gcc.gnu.org/PR15096 15788 85. https://gcc.gnu.org/PR15287 15789 86. https://gcc.gnu.org/PR15317 15790 87. https://gcc.gnu.org/PR15337 15791 88. https://gcc.gnu.org/PR15361 15792 89. https://gcc.gnu.org/PR15412 15793 90. https://gcc.gnu.org/PR15427 15794 91. https://gcc.gnu.org/PR15471 15795 92. https://gcc.gnu.org/PR15503 15796 93. https://gcc.gnu.org/PR15507 15797 94. https://gcc.gnu.org/PR15542 15798 95. https://gcc.gnu.org/PR15565 15799 96. https://gcc.gnu.org/PR15625 15800 97. https://gcc.gnu.org/PR15629 15801 98. https://gcc.gnu.org/PR15742 15802 99. https://gcc.gnu.org/PR15775 15803 100. https://gcc.gnu.org/PR15821 15804 101. https://gcc.gnu.org/PR15862 15805 102. https://gcc.gnu.org/PR15875 15806 103. https://gcc.gnu.org/PR15877 15807 104. https://gcc.gnu.org/PR15947 15808 105. https://gcc.gnu.org/PR16020 15809 106. https://gcc.gnu.org/PR16154 15810 107. https://gcc.gnu.org/PR16174 15811 108. https://gcc.gnu.org/PR14315 15812 109. https://gcc.gnu.org/PR15151 15813 110. https://gcc.gnu.org/PR7993 15814 111. https://gcc.gnu.org/PR15228 15815 112. https://gcc.gnu.org/PR15345 15816 113. https://gcc.gnu.org/PR15945 15817 114. https://gcc.gnu.org/PR15526 15818 115. https://gcc.gnu.org/PR14690 15819 116. https://gcc.gnu.org/PR15112 15820 117. https://gcc.gnu.org/PR15067 15821 118. https://gcc.gnu.org/PR1963 15822 119. https://gcc.gnu.org/PR15717 15823 120. https://gcc.gnu.org/PR14782 15824 121. https://gcc.gnu.org/PR14828 15825 122. https://gcc.gnu.org/PR15202 15826 123. https://gcc.gnu.org/PR14610 15827 124. https://gcc.gnu.org/PR14813 15828 125. https://gcc.gnu.org/PR14857 15829 126. https://gcc.gnu.org/PR15598 15830 127. https://gcc.gnu.org/PR15653 15831 128. https://gcc.gnu.org/PR15189 15832 129. https://gcc.gnu.org/PR15331 15833 130. https://gcc.gnu.org/PR16144 15834 131. https://gcc.gnu.org/PR16176 15835 132. https://gcc.gnu.org/PR11591 15836 133. https://gcc.gnu.org/PR12028 15837 134. https://gcc.gnu.org/PR14478 15838 135. https://gcc.gnu.org/PR14567 15839 136. https://gcc.gnu.org/PR14715 15840 137. https://gcc.gnu.org/PR14902 15841 138. https://gcc.gnu.org/PR14924 15842 139. https://gcc.gnu.org/PR14960 15843 140. https://gcc.gnu.org/PR15106 15844 141. https://gcc.gnu.org/PR16026 15845 142. https://gcc.gnu.org/PR15191 15846 143. https://gcc.gnu.org/PR15662 15847 144. https://gcc.gnu.org/PR15054 15848 145. https://gcc.gnu.org/PR15783 15849 146. https://gcc.gnu.org/PR15626 15850 147. https://gcc.gnu.org/PR14326 15851 148. https://gcc.gnu.org/PR14723 15852 149. https://gcc.gnu.org/PR15290 15853 150. https://gcc.gnu.org/PR15250 15854 151. https://gcc.gnu.org/PR15551 15855 152. https://gcc.gnu.org/PR8309 15856 153. https://gcc.gnu.org/PR13250 15857 154. https://gcc.gnu.org/PR13803 15858 155. https://gcc.gnu.org/PR14093 15859 156. https://gcc.gnu.org/PR14457 15860 157. https://gcc.gnu.org/PR14542 15861 158. https://gcc.gnu.org/PR15100 15862 159. https://gcc.gnu.org/PR15296 15863 160. https://gcc.gnu.org/PR15396 15864 161. https://gcc.gnu.org/PR15782 15865 162. https://gcc.gnu.org/PR11610 15866 163. https://gcc.gnu.org/PR15488 15867 164. https://gcc.gnu.org/PR15489 15868 165. https://gcc.gnu.org/PR13928 15869 166. https://gcc.gnu.org/PR14150 15870 167. https://gcc.gnu.org/PR14949 15871 168. https://gcc.gnu.org/PR15123 15872 169. https://gcc.gnu.org/PR16469 15873 170. https://gcc.gnu.org/PR16344 15874 171. https://gcc.gnu.org/PR16842 15875 172. https://gcc.gnu.org/PR12608 15876 173. https://gcc.gnu.org/PR14492 15877 174. https://gcc.gnu.org/PR15461 15878 175. https://gcc.gnu.org/PR15890 15879 176. https://gcc.gnu.org/PR16180 15880 177. https://gcc.gnu.org/PR16224 15881 178. https://gcc.gnu.org/PR16408 15882 179. https://gcc.gnu.org/PR16529 15883 180. https://gcc.gnu.org/PR16698 15884 181. https://gcc.gnu.org/PR16706 15885 182. https://gcc.gnu.org/PR16810 15886 183. https://gcc.gnu.org/PR16851 15887 184. https://gcc.gnu.org/PR16870 15888 185. https://gcc.gnu.org/PR16904 15889 186. https://gcc.gnu.org/PR16905 15890 187. https://gcc.gnu.org/PR16964 15891 188. https://gcc.gnu.org/PR17068 15892 189. https://gcc.gnu.org/PR16366 15893 190. https://gcc.gnu.org/PR15345 15894 191. https://gcc.gnu.org/PR16590 15895 192. https://gcc.gnu.org/PR16693 15896 193. https://gcc.gnu.org/PR17078 15897 194. https://gcc.gnu.org/PR13956 15898 195. https://gcc.gnu.org/PR16684 15899 196. https://gcc.gnu.org/PR12658 15900 197. https://gcc.gnu.org/PR13092 15901 198. https://gcc.gnu.org/PR15320 15902 199. https://gcc.gnu.org/PR16246 15903 200. https://gcc.gnu.org/PR16273 15904 201. https://gcc.gnu.org/PR16401 15905 202. https://gcc.gnu.org/PR16411 15906 203. https://gcc.gnu.org/PR16489 15907 204. https://gcc.gnu.org/PR16618 15908 205. https://gcc.gnu.org/PR16637 15909 206. https://gcc.gnu.org/PR16717 15910 207. https://gcc.gnu.org/PR16813 15911 208. https://gcc.gnu.org/PR16853 15912 209. https://gcc.gnu.org/PR16889 15913 210. https://gcc.gnu.org/PR16959 15914 211. https://gcc.gnu.org/PR7587 15915 212. https://gcc.gnu.org/PR16473 15916 213. https://gcc.gnu.org/PR16478 15917 214. https://gcc.gnu.org/PR10695 15918 215. https://gcc.gnu.org/PR16974 15919 216. https://gcc.gnu.org/PR16298 15920 217. https://gcc.gnu.org/PR17113 15921 218. https://gcc.gnu.org/PR14697 15922 219. https://gcc.gnu.org/PR15869 15923 220. https://gcc.gnu.org/PR16325 15924 221. https://gcc.gnu.org/PR16357 15925 222. https://gcc.gnu.org/PR16380 15926 223. https://gcc.gnu.org/PR16407 15927 224. https://gcc.gnu.org/PR16643 15928 225. https://gcc.gnu.org/PR15927 15929 226. https://gcc.gnu.org/PR15948 15930 227. https://gcc.gnu.org/PR17019 15931 228. https://gcc.gnu.org/PR16130 15932 229. https://gcc.gnu.org/PR16142 15933 230. https://gcc.gnu.org/PR16278 15934 231. https://gcc.gnu.org/PR16414 15935 232. https://gcc.gnu.org/PR16445 15936 233. https://gcc.gnu.org/PR16490 15937 234. https://gcc.gnu.org/PR16683 15938 235. https://gcc.gnu.org/PR16195 15939 236. https://gcc.gnu.org/PR16239 15940 237. https://gcc.gnu.org/PR16199 15941 238. https://gcc.gnu.org/PR16416 15942 239. https://gcc.gnu.org/PR16430 15943 240. https://gcc.gnu.org/PR16379 15944 241. https://gcc.gnu.org/PR17093 15945 242. https://gcc.gnu.org/PR17119 15946 243. https://gcc.gnu.org/PR15928 15947 244. https://gcc.gnu.org/PR16210 15948 245. https://gcc.gnu.org/PR15488 15949 246. https://gcc.gnu.org/PR16250 15950 247. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=3.4.3 15951 248. https://gcc.gnu.org/PR17369 15952 249. https://gcc.gnu.org/PR17850 15953 250. https://gcc.gnu.org/PR13948 15954 251. https://gcc.gnu.org/PR14492 15955 252. https://gcc.gnu.org/PR16301 15956 253. https://gcc.gnu.org/PR16566 15957 254. https://gcc.gnu.org/PR17023 15958 255. https://gcc.gnu.org/PR17027 15959 256. https://gcc.gnu.org/PR17524 15960 257. https://gcc.gnu.org/PR17826 15961 258. https://gcc.gnu.org/PR15526 15962 259. https://gcc.gnu.org/PR16999 15963 260. https://gcc.gnu.org/PR17503 15964 261. https://gcc.gnu.org/PR17581 15965 262. https://gcc.gnu.org/PR18129 15966 263. https://gcc.gnu.org/PR10975 15967 264. https://gcc.gnu.org/PR11722 15968 265. https://gcc.gnu.org/PR14534 15969 266. https://gcc.gnu.org/PR15172 15970 267. https://gcc.gnu.org/PR15786 15971 268. https://gcc.gnu.org/PR16162 15972 269. https://gcc.gnu.org/PR16612 15973 270. https://gcc.gnu.org/PR16715 15974 271. https://gcc.gnu.org/PR16848 15975 272. https://gcc.gnu.org/PR17132 15976 273. https://gcc.gnu.org/PR17259 15977 274. https://gcc.gnu.org/PR17327 15978 275. https://gcc.gnu.org/PR17393 15979 276. https://gcc.gnu.org/PR17501 15980 277. https://gcc.gnu.org/PR17537 15981 278. https://gcc.gnu.org/PR17585 15982 279. https://gcc.gnu.org/PR17821 15983 280. https://gcc.gnu.org/PR17829 15984 281. https://gcc.gnu.org/PR17851 15985 282. https://gcc.gnu.org/PR17976 15986 283. https://gcc.gnu.org/PR18020 15987 284. https://gcc.gnu.org/PR18093 15988 285. https://gcc.gnu.org/PR18140 15989 286. https://gcc.gnu.org/PR17541 15990 287. https://gcc.gnu.org/PR17853 15991 288. https://gcc.gnu.org/PR17245 15992 289. https://gcc.gnu.org/PR17167 15993 290. https://gcc.gnu.org/PR17277 15994 291. https://gcc.gnu.org/PR17505 15995 292. https://gcc.gnu.org/PR17684 15996 293. https://gcc.gnu.org/PR17384 15997 294. https://gcc.gnu.org/PR17770 15998 295. https://gcc.gnu.org/PR11476 15999 296. https://gcc.gnu.org/PR14064 16000 297. https://gcc.gnu.org/PR14678 16001 298. https://gcc.gnu.org/PR15583 16002 299. https://gcc.gnu.org/PR15790 16003 300. https://gcc.gnu.org/PR15886 16004 301. https://gcc.gnu.org/PR16884 16005 302. https://gcc.gnu.org/PR13841 16006 303. https://gcc.gnu.org/PR15860 16007 304. https://gcc.gnu.org/PR17465 16008 305. https://gcc.gnu.org/PR17469 16009 306. https://gcc.gnu.org/PR18138 16010 307. https://gcc.gnu.org/PR15498 16011 308. https://gcc.gnu.org/PR15747 16012 309. https://gcc.gnu.org/PR16406 16013 310. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=3.4.4 16014 311. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=3.4.5 16015 312. https://gcc.gnu.org/PR24688 16016 313. https://gcc.gnu.org/PR17188 16017 314. https://gcc.gnu.org/PR20187 16018 315. https://gcc.gnu.org/PR21873 16019 316. https://gcc.gnu.org/PR21899 16020 317. https://gcc.gnu.org/PR22061 16021 318. https://gcc.gnu.org/PR22208 16022 319. https://gcc.gnu.org/PR22458 16023 320. https://gcc.gnu.org/PR22589 16024 321. https://gcc.gnu.org/PR24101 16025 322. https://gcc.gnu.org/PR10611 16026 323. https://gcc.gnu.org/PR13377 16027 324. https://gcc.gnu.org/PR16002 16028 325. https://gcc.gnu.org/PR17413 16029 326. https://gcc.gnu.org/PR17609 16030 327. https://gcc.gnu.org/PR17618 16031 328. https://gcc.gnu.org/PR18124 16032 329. https://gcc.gnu.org/PR18155 16033 330. https://gcc.gnu.org/PR18177 16034 331. https://gcc.gnu.org/PR18368 16035 332. https://gcc.gnu.org/PR18378 16036 333. https://gcc.gnu.org/PR18466 16037 334. https://gcc.gnu.org/PR18512 16038 335. https://gcc.gnu.org/PR18545 16039 336. https://gcc.gnu.org/PR18738 16040 337. https://gcc.gnu.org/PR18803 16041 338. https://gcc.gnu.org/PR19004 16042 339. https://gcc.gnu.org/PR19208 16043 340. https://gcc.gnu.org/PR19253 16044 341. https://gcc.gnu.org/PR19608 16045 342. https://gcc.gnu.org/PR19884 16046 343. https://gcc.gnu.org/PR20153 16047 344. https://gcc.gnu.org/PR20563 16048 345. https://gcc.gnu.org/PR20789 16049 346. https://gcc.gnu.org/PR21336 16050 347. https://gcc.gnu.org/PR21768 16051 348. https://gcc.gnu.org/PR21853 16052 349. https://gcc.gnu.org/PR21903 16053 350. https://gcc.gnu.org/PR21983 16054 351. https://gcc.gnu.org/PR21987 16055 352. https://gcc.gnu.org/PR22153 16056 353. https://gcc.gnu.org/PR22172 16057 354. https://gcc.gnu.org/PR21286 16058 355. https://gcc.gnu.org/PR22233 16059 356. https://gcc.gnu.org/PR22508 16060 357. https://gcc.gnu.org/PR22545 16061 358. https://gcc.gnu.org/PR23528 16062 359. https://gcc.gnu.org/PR23550 16063 360. https://gcc.gnu.org/PR23586 16064 361. https://gcc.gnu.org/PR23624 16065 362. https://gcc.gnu.org/PR23639 16066 363. https://gcc.gnu.org/PR23797 16067 364. https://gcc.gnu.org/PR23965 16068 365. https://gcc.gnu.org/PR24052 16069 366. https://gcc.gnu.org/PR24580 16070 367. https://gcc.gnu.org/PR24267 16071 368. https://gcc.gnu.org/PR17810 16072 369. https://gcc.gnu.org/PR17860 16073 370. https://gcc.gnu.org/PR21709 16074 371. https://gcc.gnu.org/PR21964 16075 372. https://gcc.gnu.org/PR22167 16076 373. https://gcc.gnu.org/PR22619 16077 374. https://gcc.gnu.org/PR23241 16078 375. https://gcc.gnu.org/PR23478 16079 376. https://gcc.gnu.org/PR24470 16080 377. https://gcc.gnu.org/PR24950 16081 378. https://gcc.gnu.org/PR14400 16082 379. https://gcc.gnu.org/PR14940 16083 380. https://gcc.gnu.org/PR20239 16084 381. https://gcc.gnu.org/PR15220 16085 382. https://gcc.gnu.org/PR19275 16086 383. https://gcc.gnu.org/PR21888 16087 384. https://gcc.gnu.org/PR15342 16088 385. https://gcc.gnu.org/PR23985 16089 386. https://gcc.gnu.org/PR16719 16090 387. https://gcc.gnu.org/PR21723 16091 388. https://gcc.gnu.org/PR21841 16092 389. https://gcc.gnu.org/PR23644 16093 390. https://gcc.gnu.org/PR24718 16094 391. https://gcc.gnu.org/PR18421 16095 392. https://gcc.gnu.org/PR20621 16096 393. https://gcc.gnu.org/PR18583 16097 394. https://gcc.gnu.org/PR20191 16098 395. https://gcc.gnu.org/PR22083 16099 396. https://gcc.gnu.org/PR23070 16100 397. https://gcc.gnu.org/PR23404 16101 398. https://gcc.gnu.org/PR23539 16102 399. https://gcc.gnu.org/PR24102 16103 400. https://gcc.gnu.org/PR24465 16104 401. https://gcc.gnu.org/PR19933 16105 402. https://gcc.gnu.org/PR21889 16106 403. https://gcc.gnu.org/PR19300 16107 404. https://gcc.gnu.org/PR20301 16108 405. https://gcc.gnu.org/PR20673 16109 406. https://gcc.gnu.org/PR18582 16110 407. https://gcc.gnu.org/PR19340 16111 408. https://gcc.gnu.org/PR21716 16112 409. https://gcc.gnu.org/PR24315 16113 410. https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=3.4.6 16114 411. https://gcc.gnu.org/onlinedocs/ 16115 412. mailto:gcc-help (a] gcc.gnu.org 16116 413. mailto:gcc (a] gcc.gnu.org 16117 414. https://gcc.gnu.org/lists.html 16118 415. https://www.fsf.org/ 16119 416. https://gcc.gnu.org/about.html 16120 ====================================================================== 16121 http://gcc.gnu.org/gcc-3.3/index.html 16122 16123 GCC 3.3 Release Series 16124 16125 (This release series is no longer supported.) 16126 16127 May 03, 2005 16128 16129 The [1]GNU project and the GCC developers are pleased to announce the 16130 release of GCC 3.3.6. 16131 16132 This release is a bug-fix release, containing fixes for regressions in 16133 GCC 3.3.5 relative to previous releases of GCC. 16134 16135 This release is the last of the series 3.3.x. 16136 16137 The GCC 3.3 release series includes numerous [2]new features, 16138 improvements, bug fixes, and other changes, thanks to an [3]amazing 16139 group of volunteers. 16140 16141 Release History 16142 16143 GCC 3.3.6 16144 May 3, 2005 ([4]changes) 16145 16146 GCC 3.3.5 16147 September 30, 2004 ([5]changes) 16148 16149 GCC 3.3.4 16150 May 31, 2004 ([6]changes) 16151 16152 GCC 3.3.3 16153 February 14, 2004 ([7]changes) 16154 16155 GCC 3.3.2 16156 October 16, 2003 ([8]changes) 16157 16158 GCC 3.3.1 16159 August 8, 2003 ([9]changes) 16160 16161 GCC 3.3 16162 May 14, 2003 ([10]changes) 16163 16164 References and Acknowledgements 16165 16166 GCC used to stand for the GNU C Compiler, but since the compiler 16167 supports several other languages aside from C, it now stands for the 16168 GNU Compiler Collection. 16169 16170 A list of [11]successful builds is updated as new information becomes 16171 available. 16172 16173 The GCC developers would like to thank the numerous people that have 16174 contributed new features, improvements, bug fixes, and other changes as 16175 well as test results to GCC. This [12]amazing group of volunteers is 16176 what makes GCC successful. 16177 16178 For additional information about GCC please refer to the [13]GCC 16179 project web site or contact the [14]GCC development mailing list. 16180 16181 To obtain GCC please use [15]our mirror sites, or our CVS server. 16182 16183 16184 For questions related to the use of GCC, please consult these web 16185 pages and the [16]GCC manuals. If that fails, the 16186 [17]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 16187 web pages and the development of GCC are welcome on our developer 16188 list at [18]gcc (a] gcc.gnu.org. All of [19]our lists have public 16189 archives. 16190 16191 Copyright (C) [20]Free Software Foundation, Inc. Verbatim copying and 16192 distribution of this entire article is permitted in any medium, 16193 provided this notice is preserved. 16194 16195 These pages are [21]maintained by the GCC team. Last modified 16196 2022-10-26. 16197 16198 References 16199 16200 1. http://www.gnu.org/ 16201 2. http://gcc.gnu.org/gcc-3.3/changes.html 16202 3. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 16203 4. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.6 16204 5. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.5 16205 6. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.4 16206 7. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.3 16207 8. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.2 16208 9. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.1 16209 10. http://gcc.gnu.org/gcc-3.3/changes.html 16210 11. http://gcc.gnu.org/gcc-3.3/buildstat.html 16211 12. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 16212 13. http://gcc.gnu.org/index.html 16213 14. mailto:gcc (a] gcc.gnu.org 16214 15. http://gcc.gnu.org/mirrors.html 16215 16. https://gcc.gnu.org/onlinedocs/ 16216 17. mailto:gcc-help (a] gcc.gnu.org 16217 18. mailto:gcc (a] gcc.gnu.org 16218 19. https://gcc.gnu.org/lists.html 16219 20. https://www.fsf.org/ 16220 21. https://gcc.gnu.org/about.html 16221 ====================================================================== 16222 http://gcc.gnu.org/gcc-3.3/changes.html 16223 16224 GCC 3.3 Release Series 16225 Changes, New Features, and Fixes 16226 16227 The latest release in the 3.3 release series is [1]GCC 3.3.6. 16228 16229 Caveats 16230 16231 * The preprocessor no longer accepts multi-line string literals. They 16232 were deprecated in 3.0, 3.1, and 3.2. 16233 * The preprocessor no longer supports the -A- switch when appearing 16234 alone. -A- followed by an assertion is still supported. 16235 * Support for all the systems [2]obsoleted in GCC 3.1 has been 16236 removed from GCC 3.3. See below for a [3]list of systems which are 16237 obsoleted in this release. 16238 * Checking for null format arguments has been decoupled from the rest 16239 of the format checking mechanism. Programs which use the format 16240 attribute may regain this functionality by using the new [4]nonnull 16241 function attribute. Note that all functions for which GCC has a 16242 built-in format attribute, an appropriate built-in nonnull 16243 attribute is also applied. 16244 * The DWARF (version 1) debugging format has been deprecated and will 16245 be removed in a future version of GCC. Version 2 of the DWARF 16246 debugging format will continue to be supported for the foreseeable 16247 future. 16248 * The C and Objective-C compilers no longer accept the "Naming Types" 16249 extension (typedef foo = bar); it was already unavailable in C++. 16250 Code which uses it will need to be changed to use the "typeof" 16251 extension instead: typedef typeof(bar) foo. (We have removed this 16252 extension without a period of deprecation because it has caused the 16253 compiler to crash since version 3.0 and no one noticed until very 16254 recently. Thus we conclude it is not in widespread use.) 16255 * The -traditional C compiler option has been removed. It was 16256 deprecated in 3.1 and 3.2. (Traditional preprocessing remains 16257 available.) The <varargs.h> header, used for writing variadic 16258 functions in traditional C, still exists but will produce an error 16259 message if used. 16260 * GCC 3.3.1 automatically places zero-initialized variables in the 16261 .bss section on some operating systems. Versions of GNU Emacs up to 16262 (and including) 21.3 will not work correctly when using this 16263 optimization; you can use -fno-zero-initialized-in-bss to disable 16264 it. 16265 16266 General Optimizer Improvements 16267 16268 * A new scheme for accurately describing processor pipelines, the 16269 [5]DFA scheduler, has been added. 16270 * Pavel Nejedly, Charles University Prague, has contributed new file 16271 format used by the edge coverage profiler (-fprofile-arcs). 16272 The new format is robust and diagnoses common mistakes where 16273 profiles from different versions (or compilations) of the program 16274 are combined resulting in nonsensical profiles and slow code to 16275 produced with profile feedback. Additionally this format allows 16276 extra data to be gathered. Currently, overall statistics are 16277 produced helping optimizers to identify hot spots of a program 16278 globally replacing the old intra-procedural scheme and resulting in 16279 better code. Note that the gcov tool from older GCC versions will 16280 not be able to parse the profiles generated by GCC 3.3 and vice 16281 versa. 16282 * Jan Hubicka, SuSE Labs, has contributed a new superblock formation 16283 pass enabled using -ftracer. This pass simplifies the control flow 16284 of functions allowing other optimizations to do better job. 16285 He also contributed the function reordering pass 16286 (-freorder-functions) to optimize function placement using profile 16287 feedback. 16288 16289 New Languages and Language specific improvements 16290 16291 C/ObjC/C++ 16292 16293 * The preprocessor now accepts directives within macro arguments. It 16294 processes them just as if they had not been within macro arguments. 16295 * The separate ISO and traditional preprocessors have been completely 16296 removed. The front end handles either type of preprocessed output 16297 if necessary. 16298 * In C99 mode preprocessor arithmetic is done in the precision of the 16299 target's intmax_t, as required by that standard. 16300 * The preprocessor can now copy comments inside macros to the output 16301 file when the macro is expanded. This feature, enabled using the 16302 -CC option, is intended for use by applications which place 16303 metadata or directives inside comments, such as lint. 16304 * The method of constructing the list of directories to be searched 16305 for header files has been revised. If a directory named by a -I 16306 option is a standard system include directory, the option is 16307 ignored to ensure that the default search order for system 16308 directories and the special treatment of system header files are 16309 not defeated. 16310 * A few more [6]ISO C99 features now work correctly. 16311 * A new function attribute, nonnull, has been added which allows 16312 pointer arguments to functions to be specified as requiring a 16313 non-null value. The compiler currently uses this information to 16314 issue a warning when it detects a null value passed in such an 16315 argument slot. 16316 * A new type attribute, may_alias, has been added. Accesses to 16317 objects with types with this attribute are not subjected to 16318 type-based alias analysis, but are instead assumed to be able to 16319 alias any other type of objects, just like the char type. 16320 16321 C++ 16322 16323 * Type based alias analysis has been implemented for C++ aggregate 16324 types. 16325 16326 Objective-C 16327 16328 * Generate an error if Objective-C objects are passed by value in 16329 function and method calls. 16330 * When -Wselector is used, check the whole list of selectors at the 16331 end of compilation, and emit a warning if a @selector() is not 16332 known. 16333 * Define __NEXT_RUNTIME__ when compiling for the NeXT runtime. 16334 * No longer need to include objc/objc-class.h to compile self calls 16335 in class methods (NeXT runtime only). 16336 * New -Wundeclared-selector option. 16337 * Removed selector bloating which was causing object files to be 10% 16338 bigger on average (GNU runtime only). 16339 * Using at run time @protocol() objects has been fixed in certain 16340 situations (GNU runtime only). 16341 * Type checking has been fixed and improved in many situations 16342 involving protocols. 16343 16344 Java 16345 16346 * The java.sql and javax.sql packages now implement the JDBC 3.0 (JDK 16347 1.4) API. 16348 * The JDK 1.4 assert facility has been implemented. 16349 * The bytecode interpreter is now direct threaded and thus faster. 16350 16351 Fortran 16352 16353 * Fortran improvements are listed in [7]the Fortran documentation. 16354 16355 Ada 16356 16357 * Ada tasking now works with glibc 2.3.x threading libraries. 16358 16359 New Targets and Target Specific Improvements 16360 16361 * The following changes have been made to the HP-PA port: 16362 + The port now defaults to scheduling for the PA8000 series of 16363 processors. 16364 + Scheduling support for the PA7300 processor has been added. 16365 + The 32-bit port now supports weak symbols under HP-UX 11. 16366 + The handling of initializers and finalizers has been improved 16367 under HP-UX 11. The 64-bit port no longer uses collect2. 16368 + Dwarf2 EH support has been added to the 32-bit GNU/Linux port. 16369 + ABI fixes to correct the passing of small structures by value. 16370 * The SPARC, HP-PA, SH4, and x86/pentium ports have been converted to 16371 use the DFA processor pipeline description. 16372 * The following NetBSD configurations for the SuperH processor family 16373 have been added: 16374 + SH3, big-endian, sh-*-netbsdelf* 16375 + SH3, little-endian, shle-*-netbsdelf* 16376 + SH5, SHmedia, big-endian, 32-bit default, sh5-*-netbsd* 16377 + SH5, SHmedia, little-endian, 32-bit default, sh5le-*-netbsd* 16378 + SH5, SHmedia, big-endian, 64-bit default, sh64-*-netbsd* 16379 + SH5, SHmedia, little-endian, 64-bit default, sh64le-*-netbsd* 16380 * The following changes have been made to the IA-32/x86-64 port: 16381 + SSE2 and 3dNOW! intrinsics are now supported. 16382 + Support for thread local storage has been added to the IA-32 16383 and x86-64 ports. 16384 + The x86-64 port has been significantly improved. 16385 * The following changes have been made to the MIPS port: 16386 + All configurations now accept the -mabi switch. Note that you 16387 will need appropriate multilibs for this option to work 16388 properly. 16389 + ELF configurations will always pass an ABI flag to the 16390 assembler, except when the MIPS EABI is selected. 16391 + -mabi=64 no longer selects MIPS IV code. 16392 + The -mcpu option, which was deprecated in 3.1 and 3.2, has 16393 been removed from this release. 16394 + -march now changes the core ISA level. In previous releases, 16395 it would change the use of processor-specific extensions, but 16396 would leave the core ISA unchanged. For example, mips64-elf 16397 -march=r8000 will now generate MIPS IV code. 16398 + Under most configurations, -mipsN now acts as a synonym for 16399 -march. 16400 + There are some new preprocessor macros to describe the -march 16401 and -mtune settings. See the documentation of those options 16402 for details. 16403 + Support for the NEC VR-Series processors has been added. This 16404 includes the 54xx, 5500, and 41xx series. 16405 + Support for the Sandcraft sr71k processor has been added. 16406 * The following changes have been made to the S/390 port: 16407 + Support to build the Java runtime libraries has been added. 16408 Java is now enabled by default on s390-*-linux* and 16409 s390x-*-linux* targets. 16410 + Multilib support for the s390x-*-linux* target has been added; 16411 this allows to build 31-bit binaries using the -m31 option. 16412 + Support for thread local storage has been added. 16413 + Inline assembler code may now use the 'Q' constraint to 16414 specify memory operands without index register. 16415 + Various platform-specific performance improvements have been 16416 implemented; in particular, the compiler now uses the BRANCH 16417 ON COUNT family of instructions and makes more frequent use of 16418 the TEST UNDER MASK family of instructions. 16419 * The following changes have been made to the PowerPC port: 16420 + Support for IBM Power4 processor added. 16421 + Support for Motorola e500 SPE added. 16422 + Support for AIX 5.2 added. 16423 + Function and Data sections now supported on AIX. 16424 + Sibcall optimizations added. 16425 * The support for H8 Tiny is added to the H8/300 port with -mn. 16426 16427 Obsolete Systems 16428 16429 Support for a number of older systems has been declared obsolete in GCC 16430 3.3. Unless there is activity to revive them, the next release of GCC 16431 will have their sources permanently removed. 16432 16433 All configurations of the following processor architectures have been 16434 declared obsolete: 16435 * Matsushita MN10200, mn10200-*-* 16436 * Motorola 88000, m88k-*-* 16437 * IBM ROMP, romp-*-* 16438 16439 Also, some individual systems have been obsoleted: 16440 * Alpha 16441 + Interix, alpha*-*-interix* 16442 + Linux libc1, alpha*-*-linux*libc1* 16443 + Linux ECOFF, alpha*-*-linux*ecoff* 16444 * ARM 16445 + Generic a.out, arm*-*-aout* 16446 + Conix, arm*-*-conix* 16447 + "Old ABI," arm*-*-oabi 16448 + StrongARM/COFF, strongarm-*-coff* 16449 * HPPA (PA-RISC) 16450 + Generic OSF, hppa1.0-*-osf* 16451 + Generic BSD, hppa1.0-*-bsd* 16452 + HP/UX versions 7, 8, and 9, hppa1.[01]-*-hpux[789]* 16453 + HiUX, hppa*-*-hiux* 16454 + Mach Lites, hppa*-*-lites* 16455 * Intel 386 family 16456 + Windows NT 3.x, i?86-*-win32 16457 * MC68000 family 16458 + HP systems, m68000-hp-bsd* and m68k-hp-bsd* 16459 + Sun systems, m68000-sun-sunos*, m68k-sun-sunos*, and 16460 m68k-sun-mach* 16461 + AT&T systems, m68000-att-sysv* 16462 + Atari systems, m68k-atari-sysv* 16463 + Motorola systems, m68k-motorola-sysv* 16464 + NCR systems, m68k-ncr-sysv* 16465 + Plexus systems, m68k-plexus-sysv* 16466 + Commodore systems, m68k-cbm-sysv* 16467 + Citicorp TTI, m68k-tti-* 16468 + Unos, m68k-crds-unos* 16469 + Concurrent RTU, m68k-ccur-rtu* 16470 + Linux a.out, m68k-*-linux*aout* 16471 + Linux libc1, m68k-*-linux*libc1* 16472 + pSOS, m68k-*-psos* 16473 * MIPS 16474 + Generic ECOFF, mips*-*-ecoff* 16475 + SINIX, mips-sni-sysv4 16476 + Orion RTEMS, mips64orion-*-rtems* 16477 * National Semiconductor 32000 16478 + OpenBSD, ns32k-*-openbsd* 16479 * POWER (aka RS/6000) and PowerPC 16480 + AIX versions 1, 2, and 3, rs6000-ibm-aix[123]* 16481 + Bull BOSX, rs6000-bull-bosx 16482 + Generic Mach, rs6000-*-mach* 16483 + Generic SysV, powerpc*-*-sysv* 16484 + Linux libc1, powerpc*-*-linux*libc1* 16485 * Sun SPARC 16486 + Generic a.out, sparc-*-aout*, sparclet-*-aout*, 16487 sparclite-*-aout*, and sparc86x-*-aout* 16488 + NetBSD a.out, sparc-*-netbsd*aout* 16489 + Generic BSD, sparc-*-bsd* 16490 + ChorusOS, sparc-*-chorusos* 16491 + Linux a.out, sparc-*-linux*aout* 16492 + Linux libc1, sparc-*-linux*libc1* 16493 + LynxOS, sparc-*-lynxos* 16494 + Solaris on HAL hardware, sparc-hal-solaris2* 16495 + SunOS versions 3 and 4, sparc-*-sunos[34]* 16496 * NEC V850 16497 + RTEMS, v850-*-rtems* 16498 * VAX 16499 + VMS, vax-*-vms* 16500 16501 Documentation improvements 16502 16503 Other significant improvements 16504 16505 * Almost all front-end dependencies in the compiler have been 16506 separated out into a set of language hooks. This should make adding 16507 a new front end clearer and easier. 16508 * One effect of removing the separate preprocessor is a small 16509 increase in the robustness of the compiler in general, and the 16510 maintainability of target descriptions. Previously target-specific 16511 built-in macros and others, such as __FAST_MATH__, had to be 16512 handled with so-called specs that were hard to maintain. Often they 16513 would fail to behave properly when conflicting options were 16514 supplied on the command line, and define macros in the user's 16515 namespace even when strict ISO compliance was requested. 16516 Integrating the preprocessor has cleanly solved these issues. 16517 * The Makefile suite now supports redirection of make install by 16518 means of the variable DESTDIR. 16519 __________________________________________________________________ 16520 16521 GCC 3.3 16522 16523 Detailed release notes for the GCC 3.3 release follow. 16524 16525 Bug Fixes 16526 16527 bootstrap failures 16528 16529 * [8]10140 cross compiler build failures: missing __mempcpy (DUP: 16530 [9]10198,[10]10338) 16531 16532 Internal compiler errors (multi-platform) 16533 16534 * [11]3581 large string causes segmentation fault in cc1 16535 * [12]4382 __builtin_{set,long}jmp with -O3 can crash the compiler 16536 * [13]5533 (c++) ICE when processing std::accumulate(begin, end, 16537 init, invalid_op) 16538 * [14]6387 -fpic -gdwarf-2 -g1 combination gives ICE in dwarf2out 16539 * [15]6412 (c++) ICE in retrieve_specialization 16540 * [16]6620 (c++) partial template specialization causes an ICE 16541 (segmentation fault) 16542 * [17]6663 (c++) ICE with attribute aligned 16543 * [18]7068 ICE with incomplete types 16544 * [19]7083 (c++) ICE using -gstabs with dodgy class derivation 16545 * [20]7647 (c++) ICE when data member has the name of the enclosing 16546 class 16547 * [21]7675 ICE in fixup_var_refs_1 16548 * [22]7718 'complex' template instantiation causes ICE 16549 * [23]8116 (c++) ICE in member template function 16550 * [24]8358 (ada) Ada compiler accesses freed memory, crashes 16551 * [25]8511 (c++) ICE: (hopefully) reproducible cc1plus segmentation 16552 fault 16553 * [26]8564 (c++) ICE in find_function_data, in function.c 16554 * [27]8660 (c++) template overloading ICE in tsubst_expr, in cp/pt.c 16555 * [28]8766 (c++) ICE after failed initialization of static template 16556 variable 16557 * [29]8803 ICE in instantiate_virtual_regs_1, in function.c 16558 * [30]8846 (c++) ICE after diagnostic if fr_FR@euro locale is set 16559 * [31]8906 (c++) ICE (Segmentation fault) when parsing nested-class 16560 definition 16561 * [32]9216 (c++) ICE on missing template parameter 16562 * [33]9261 (c++) ICE in arg_assoc, in cp/decl2.c 16563 * [34]9263 (fortran) ICE caused by invalid PARAMETER in implied DO 16564 loop 16565 * [35]9429 (c++) ICE in template instantiation with a pointered new 16566 operator 16567 * [36]9516 Internal error when using a big array 16568 * [37]9600 (c++) ICE with typedefs in template class 16569 * [38]9629 (c++) virtual inheritance segfault 16570 * [39]9672 (c++) ICE: Error reporting routines re-entered 16571 * [40]9749 (c++) ICE in write_expression on invalid function 16572 prototype 16573 * [41]9794 (fortran) ICE: floating point exception during constant 16574 folding 16575 * [42]9829 (c++) Missing colon in nested namespace usage causes ICE 16576 * [43]9916 (c++) ICE with noreturn function in ?: statement 16577 * [44]9936 ICE with local function and variable-length 2d array 16578 * [45]10262 (c++) cc1plus crashes with large generated code 16579 * [46]10278 (c++) ICE in parser for invalid code 16580 * [47]10446 (c++) ICE on definition of nonexistent member function of 16581 nested class in a class template 16582 * [48]10451 (c++) ICE in grokdeclarator on spurious mutable 16583 declaration 16584 * [49]10506 (c++) ICE in build_new at cp/init.c with 16585 -fkeep-inline-functions and multiple inheritance 16586 * [50]10549 (c++) ICE in store_bit_field on bitfields that exceed the 16587 precision of the declared type 16588 16589 Optimization bugs 16590 16591 * [51]2001 Inordinately long compile times in reload CSE regs 16592 * [52]2391 Exponential compilation time explosion in combine 16593 * [53]2960 Duplicate loop conditions even with -Os 16594 * [54]4046 redundant conditional branch 16595 * [55]6405 Loop-unrolling related performance regressions 16596 * [56]6798 very long compile time with large case-statement 16597 * [57]6871 const objects shouldn't be moved to .bss 16598 * [58]6909 problem w/ -Os on modified loop-2c.c test case 16599 * [59]7189 gcc -O2 -Wall does not print ``control reaches end of 16600 non-void function'' warning 16601 * [60]7642 optimization problem with signbit() 16602 * [61]8634 incorrect code for inlining of memcpy under -O2 16603 * [62]8750 Cygwin prolog generation erroneously emitting __alloca as 16604 regular function call 16605 16606 C front end 16607 16608 * [63]2161 long if-else cascade overflows parser stack 16609 * [64]4319 short accepted on typedef'd char 16610 * [65]8602 incorrect line numbers in warning messages when using 16611 inline functions 16612 * [66]9177 -fdump-translation-unit: C front end deletes function_decl 16613 AST nodes and breaks debugging dumps 16614 * [67]9853 miscompilation of non-constant structure initializer 16615 16616 c++ compiler and library 16617 16618 * [68]45 legal template specialization code is rejected (DUP: 16619 [69]3784) 16620 * [70]764 lookup failure: friend operator and dereferencing a pointer 16621 and templates (DUP: [71]5116) 16622 * [72]2862 gcc accepts invalid explicit instantiation syntax (DUP: 16623 2863) 16624 * [73]3663 G++ doesn't check access control during template 16625 instantiation 16626 * [74]3797 gcc fails to emit explicit specialization of a template 16627 member 16628 * [75]3948 Two destructors are called when no copy destructor is 16629 defined (ABI change) 16630 * [76]4137 Conversion operator within template is not accepted 16631 * [77]4361 bogus ambiguity taking the address of a member template 16632 * [78]4802 g++ accepts illegal template code (access to private 16633 member; DUP: [79]5837) 16634 * [80]4803 inline function is used but never defined, and g++ does 16635 not object 16636 * [81]5094 Partial specialization cannot be friend? 16637 * [82]5730 complex<double>::norm() -- huge slowdown from egcs-2.91.66 16638 * [83]6713 Regression wrt 3.0.4: g++ -O2 leads to seg fault at run 16639 time 16640 * [84]7015 certain __asm__ constructs rejected 16641 * [85]7086 compile time regression (quadratic behavior in 16642 fixup_var_refs) 16643 * [86]7099 G++ doesn't set the noreturn attribute on std::exit and 16644 std::abort 16645 * [87]7247 copy constructor missing when inlining enabled (invalid 16646 optimization?) 16647 * [88]7441 string array initialization compilation time regression 16648 from seconds to minutes 16649 * [89]7768 __PRETTY_FUNCTION__ for template destructor is wrong 16650 * [90]7804 bad printing of floating point constant in warning message 16651 * [91]8099 Friend classes and template specializations 16652 * [92]8117 member function pointers and multiple inheritance 16653 * [93]8205 using declaration and multiple inheritance 16654 * [94]8645 unnecessary non-zero checks in stl_tree.h 16655 * [95]8724 explicit destructor call for incomplete class allowed 16656 * [96]8805 compile time regression with many member variables 16657 * [97]8691 -O3 and -fno-implicit-templates are incompatible 16658 * [98]8700 unhelpful error message for binding temp to reference 16659 * [99]8724 explicit destructor call for incomplete class allowed 16660 * [100]8949 numeric_limits<>::denorm_min() and is_iec559 problems 16661 * [101]9016 Failure to consistently constant fold "constant" C++ 16662 objects 16663 * [102]9053 g++ confused about ambiguity of overloaded function 16664 templates 16665 * [103]9152 undefined virtual thunks 16666 * [104]9182 basic_filebuf<> does not report errors in codecvt<>::out 16667 * [105]9297 data corruption due to codegen bug (when copying.) 16668 * [106]9318 i/ostream::operator>>/<<(streambuf*) broken 16669 * [107]9320 Incorrect usage of traits_type::int_type in stdio_filebuf 16670 * [108]9400 bogus -Wshadow warning: shadowed declaration of this in 16671 local classes 16672 * [109]9424 i/ostream::operator>>/<<(streambuf*) drops characters 16673 * [110]9425 filebuf::pbackfail broken (DUP: [111]9439) 16674 * [112]9474 GCC freezes in compiling a weird code mixing <iostream> 16675 and <iostream.h> 16676 * [113]9548 Incorrect results from setf(ios::fixed) and precision(-1) 16677 [114][DR 231] 16678 * [115]9555 ostream inserters fail to set badbit on exception 16679 * [116]9561 ostream inserters rethrow exception of wrong type 16680 * [117]9563 ostream::sentry returns true after a failed preparation 16681 * [118]9582 one-definition rule violation in std::allocator 16682 * [119]9622 __PRETTY_FUNCTION__ incorrect in template destructors 16683 * [120]9683 bug in initialization chains for static const variables 16684 from template classes 16685 * [121]9791 -Woverloaded-virtual reports hiding of destructor 16686 * [122]9817 collate::compare doesn't handle nul characters 16687 * [123]9825 filebuf::sputbackc breaks sbumpc 16688 * [124]9826 operator>>(basic_istream, basic_string) fails to compile 16689 with custom traits 16690 * [125]9924 Multiple using statements for builtin functions not 16691 allowed 16692 * [126]9946 destructor is not called for temporary object 16693 * [127]9964 filebuf::close() sometimes fails to close file 16694 * [128]9988 filebuf::overflow writes EOF to file 16695 * [129]10033 optimization breaks polymorphic references w/ typeid 16696 operator 16697 * [130]10097 filebuf::underflow drops characters 16698 * [131]10132 filebuf destructor can throw exceptions 16699 * [132]10180 gcc fails to warn about non-inlined function 16700 * [133]10199 method parametrized by template does not work everywhere 16701 * [134]10300 use of array-new (nothrow) in segfaults on NULL return 16702 * [135]10427 Stack corruption with variable-length automatic arrays 16703 and virtual destructors 16704 * [136]10503 Compilation never stops in fixed_type_or_null 16705 16706 Objective-C 16707 16708 * [137]5956 selectors aren't matched properly when added to the 16709 selector table 16710 16711 Fortran compiler and library 16712 16713 * [138]1832 list directed i/o overflow hangs, -fbounds-check doesn't 16714 detect 16715 * [139]3924 g77 generates code that is rejected by GAS if COFF debug 16716 info requested 16717 * [140]5634 doc: explain that configure --prefix=~/... does not work 16718 * [141]6367 multiple repeat counts confuse namelist read into array 16719 * [142]6491 Logical operations error on logicals when using 16720 -fugly-logint 16721 * [143]6742 Generation of C++ Prototype for FORTRAN and extern "C" 16722 * [144]7113 Failure of g77.f-torture/execute/f90-intrinsic-bit.f -Os 16723 on irix6.5 16724 * [145]7236 OPEN(...,RECL=nnn,...) without ACCESS='DIRECT' should 16725 assume a direct access file 16726 * [146]7278 g77 "bug"; the executable misbehaves (with -O2 16727 -fno-automatic) 16728 * [147]7384 DATE_AND_TIME milliseconds field inactive on Windows 16729 * [148]7388 Incorrect output with 0-based array of characters 16730 * [149]8587 Double complex zero ** double precision number -> NaN 16731 instead of zero 16732 * [150]9038 -ffixed-line-length-none -x f77-cpp-input gives: Warning: 16733 unknown register name line-length-none 16734 * [151]10197 Direct access files not unformatted by default 16735 16736 Java compiler and library 16737 16738 * [152]6005 gcj fails to build rhug on alpha 16739 * [153]6389 System.getProperty("") should always throw an 16740 IllegalArgumentException 16741 * [154]6576 java.util.ResourceBundle.getResource ignores locale 16742 * [155]6652 new java.io.File("").getCanonicalFile() throws exception 16743 * [156]7060 getMethod() doesn't search super interface 16744 * [157]7073 bytecode interpreter gives wrong answer for interface 16745 getSuperclass() 16746 * [158]7180 possible bug in 16747 javax.naming.spi.NamingManager.getPlusPath() 16748 * [159]7416 java.security startup refs "GNU libgcj.security" 16749 * [160]7570 Runtime.exec with null envp: child doesn't inherit parent 16750 env (DUP: [161]7578) 16751 * [162]7611 Internal error while compiling libjava with -O 16752 * [163]7709 NullPointerException in _Jv_ResolvePoolEntry 16753 * [164]7766 ZipInputStream.available returns 0 immediately after 16754 construction 16755 * [165]7785 Calendar.getTimeInMillis/setTimeInMillis should be public 16756 * [166]7786 TimeZone.getDSTSavings() from JDK1.4 not implemented 16757 * [167]8142 '$' in class names vs. dlopen 'dynamic string tokens' 16758 * [168]8234 ZipInputStream chokes when InputStream.read() returns 16759 small chunks 16760 * [169]8415 reflection bug: exception info for Method 16761 * [170]8481 java.Random.nextInt(int) may return negative 16762 * [171]8593 Error reading GZIPped files with BufferedReader 16763 * [172]8759 java.beans.Introspector has no flushCaches() or 16764 flushFromCaches() methods 16765 * [173]8997 spin() calls Thread.sleep 16766 * [174]9253 on win32, java.io.File.listFiles("C:\\") returns pwd 16767 instead of the root content of C: 16768 * [175]9254 java::lang::Object::wait(), threads-win32.cc returns 16769 wrong return codes 16770 * [176]9271 Severe bias in java.security.SecureRandom 16771 16772 Ada compiler and library 16773 16774 * [177]6767 make gnatlib-shared fails on -laddr2line 16775 * [178]9911 gnatmake fails to link when GCC configured with 16776 --with-sjlj-exceptions=yes 16777 * [179]10020 Can't bootstrap gcc on AIX with Ada enabled 16778 * [180]10546 Ada tasking not working on Red Hat 9 16779 16780 preprocessor 16781 16782 * [181]7029 preprocessor should ignore #warning with -M 16783 16784 ARM-specific 16785 16786 * [182]2903 [arm] Optimization bug with long long arithmetic 16787 * [183]7873 arm-linux-gcc fails when assigning address to a bit field 16788 16789 FreeBSD-specific 16790 16791 * [184]7680 float functions undefined in math.h/cmath with #define 16792 _XOPEN_SOURCE 16793 16794 HP-UX or HP-PA-specific 16795 16796 * [185]8705 [HP-PA] ICE in emit_move_insn_1, in expr.c 16797 * [186]9986 [HP-UX] Incorrect transformation of fputs_unlocked to 16798 fputc_unlocked 16799 * [187]10056 [HP-PA] ICE at -O2 when building c++ code from doxygen 16800 16801 m68hc11-specific 16802 16803 * [188]6744 Bad assembler code generated: reference to pseudo 16804 register z 16805 * [189]7361 Internal compiler error in reload_cse_simplify_operands, 16806 in reload1.c 16807 16808 MIPS-specific 16809 16810 * [190]9496 [mips-linux] bug in optimizer? 16811 16812 PowerPC-specific 16813 16814 * [191]7067 -Os with -mcpu=powerpc optimizes for speed (?) instead of 16815 space 16816 * [192]8480 reload ICEs for LAPACK code on powerpc64-linux 16817 * [193]8784 [AIX] Internal compiler error in simplify_gen_subreg 16818 * [194]10315 [powerpc] ICE: in extract_insn, in recog.c 16819 16820 SPARC-specific 16821 16822 * [195]10267 (documentation) Wrong build instructions for 16823 *-*-solaris2* 16824 16825 x86-specific (Intel/AMD) 16826 16827 * [196]7916 ICE in instantiate_virtual_register_1 16828 * [197]7926 (c++) i486 instructions in header files make c++ programs 16829 crash on i386 16830 * [198]8555 ICE in gen_split_1231 16831 * [199]8994 ICE with -O -march=pentium4 16832 * [200]9426 ICE with -fssa -funroll-loops -fprofile-arcs 16833 * [201]9806 ICE in inline assembly with -fPIC flag 16834 * [202]10077 gcc -msse2 generates movd to move dwords between xmm 16835 regs 16836 * [203]10233 64-bit comparison only comparing bottom 32-bits 16837 * [204]10286 type-punning doesn't work with __m64 and -O 16838 * [205]10308 [x86] ICE with -O -fgcse or -O2 16839 __________________________________________________________________ 16840 16841 GCC 3.3.1 16842 16843 Bug Fixes 16844 16845 This section lists the problem reports (PRs) from GCC's bug tracking 16846 system that are known to be fixed in the 3.3.1 release. This list might 16847 not be complete (that is, it is possible that some PRs that have been 16848 fixed are not listed here). 16849 16850 Bootstrap failures 16851 16852 * [206]11272 [Solaris] make bootstrap fails while building libstdc++ 16853 16854 Internal compiler errors (multi-platform) 16855 16856 * [207]5754 ICE on invalid nested template class 16857 * [208]6597 ICE in set_mem_alias_set compiling Qt with -O2 on ia64 16858 and --enable-checking 16859 * [209]6949 (c++) ICE in tsubst_decl, in cp/pt.c 16860 * [210]7053 (c++) ICE when declaring a function already defined as a 16861 friend method of a template class 16862 * [211]8164 (c++) ICE when using different const expressions as 16863 template parameter 16864 * [212]8384 (c++) ICE in is_base_type, in dwarf2out.c 16865 * [213]9559 (c++) ICE with invalid initialization of a static const 16866 * [214]9649 (c++) ICE in finish_member_declaration, in cp/semantics.c 16867 when redeclaring a static member variable 16868 * [215]9864 (fortran) ICE in add_abstract_origin_attribute, in 16869 dwarfout.c with -g -O -finline-functions 16870 * [216]10432 (c++) ICE in poplevel, in cp/decl.c 16871 * [217]10475 ICE in subreg_highpart_offset for code with long long 16872 * [218]10635 (c++) ICE when dereferencing an incomplete type casted 16873 from a void pointer 16874 * [219]10661 (c++) ICE in instantiate_decl, in cp/pt.c while 16875 instantiating static member variables 16876 * [220]10700 ICE in copy_to_mode_reg on 64-bit targets 16877 * [221]10712 (c++) ICE in constructor_name_full, in cp/decl2.c 16878 * [222]10796 (c++) ICE when defining an enum with two values: -1 and 16879 MAX_INT_64BIT 16880 * [223]10890 ICE in merge_assigned_reloads building Linux 2.4.2x 16881 sched.c 16882 * [224]10939 (c++) ICE with template code 16883 * [225]10956 (c++) ICE when specializing a template member function 16884 of a template class, in tsubst, in cp/pt.c 16885 * [226]11041 (c++) ICE: const myclass &x = *x; (when operator*() 16886 defined) 16887 * [227]11059 (c++) ICE with empty union 16888 * [228]11083 (c++) ICE in commit_one_edge_insertion, in cfgrtl.c with 16889 -O2 -fnon-call-exceptions 16890 * [229]11105 (c++) ICE in mangle_conv_op_name_for_type 16891 * [230]11149 (c++) ICE on error when instantiation with call function 16892 of a base type 16893 * [231]11228 (c++) ICE on new-expression using array operator new and 16894 default-initialization 16895 * [232]11282 (c++) Infinite memory usage after syntax error 16896 * [233]11301 (fortran) ICE with -fno-globals 16897 * [234]11308 (c++) ICE when using an enum type name as if it were a 16898 class or namespace 16899 * [235]11473 (c++) ICE with -gstabs when empty struct inherits from 16900 an empty struct 16901 * [236]11503 (c++) ICE when instantiating template with ADDR_EXPR 16902 * [237]11513 (c++) ICE in push_template_decl_real, in cp/pt.c: 16903 template member functions 16904 16905 Optimization bugs 16906 16907 * [238]11198 -O2 -frename-registers generates wrong code (aliasing 16908 problem) 16909 * [239]11304 Wrong code production with -fomit-frame-pointer 16910 * [240]11381 volatile memory access optimized away 16911 * [241]11536 [strength-reduce] -O2 optimization produces wrong code 16912 * [242]11557 constant folding bug generates wrong code 16913 16914 C front end 16915 16916 * [243]5897 No warning for statement after return 16917 * [244]11279 DWARF-2 output mishandles large enums 16918 16919 Preprocessor bugs 16920 16921 * [245]11022 no warning for non-compatible macro redefinition 16922 16923 C++ compiler and library 16924 16925 * [246]2330 static_cast<>() to a private base is allowed 16926 * [247]5388 Incorrect message "operands to ?: have different types" 16927 * [248]5390 Libiberty fails to demangle multi-digit template 16928 parameters 16929 * [249]7877 Incorrect parameter passing to specializations of member 16930 function templates 16931 * [250]9393 Anonymous namespaces and compiling the same file twice 16932 * [251]10032 -pedantic converts some errors to warnings 16933 * [252]10468 const typeof(x) is non-const, but only in templates 16934 * [253]10527 confused error message with "new int()" parameter 16935 initializer 16936 * [254]10679 parameter MIN_INLINE_INSNS is not honored 16937 * [255]10682 gcc chokes on a typedef for an enum inside a class 16938 template 16939 * [256]10689 pow(std::complex(0),1/3) returns (nan, nan) instead of 16940 0. 16941 * [257]10845 template member function (with nested template as 16942 parameter) cannot be called anymore if another unrelated template 16943 member function is defined 16944 * [258]10849 Cannot define an out-of-class specialization of a 16945 private nested template class 16946 * [259]10888 Suppress -Winline warnings for system headers 16947 * [260]10929 -Winline warns about functions for which no definition 16948 is visible 16949 * [261]10931 valid conversion static_cast<const unsigned 16950 int&>(lvalue-of-type-int) is rejected 16951 * [262]10940 Bad code with explicit specialization 16952 * [263]10968 If member function implicitly instantiated, explicit 16953 instantiation of class fails to instantiate it 16954 * [264]10990 Cannot convert with dynamic_cast<> to a private base 16955 class from within a member function 16956 * [265]11039 Bad interaction between implicit typename deprecation 16957 and friendship 16958 * [266]11062 (libstdc++) avoid __attribute__ ((unused)); say 16959 "__unused__" instead 16960 * [267]11095 C++ iostream manipulator causes segfault when called 16961 with negative argument 16962 * [268]11098 g++ doesn't emit complete debugging information for 16963 local variables in destructors 16964 * [269]11137 GNU/Linux shared library constructors not called unless 16965 there's one global object 16966 * [270]11154 spurious ambiguity report for template class 16967 specialization 16968 * [271]11329 Compiler cannot find user defined implicit typecast 16969 * [272]11332 Spurious error with casts in ?: expression 16970 * [273]11431 static_cast behavior with subclasses when default 16971 constructor available 16972 * [274]11528 money_get facet does not accept "$.00" as valid 16973 * [275]11546 Type lookup problems in out-of-line definition of a 16974 class doubly nested from a template class 16975 * [276]11567 C++ code containing templated member function with same 16976 name as pure virtual member function results in linking failure 16977 * [277]11645 Failure to deal with using and private inheritance 16978 16979 Java compiler and library 16980 16981 * [278]5179 Qualified static field access doesn't initialize its 16982 class 16983 * [279]8204 gcj -O2 to native reorders certain instructions 16984 improperly 16985 * [280]10838 java.io.ObjectInputStream syntax error 16986 * [281]10886 The RMI registry that comes with GCJ does not work 16987 correctly 16988 * [282]11349 JNDI URL context factories not located correctly 16989 16990 x86-specific (Intel/AMD) 16991 16992 * [283]4823 ICE on inline assembly code 16993 * [284]8878 miscompilation with -O and SSE 16994 * [285]9815 (c++ library) atomicity.h - fails to compile with -O3 16995 -masm=intel 16996 * [286]10402 (inline assembly) [x86] ICE in merge_assigned_reloads, 16997 in reload1.c 16998 * [287]10504 ICE with SSE2 code and -O3 -mcpu=pentium4 -msse2 16999 * [288]10673 ICE for x86-64 on freebsd libc vfprintf.c source 17000 * [289]11044 [x86] out of range loop instructions for FP code on K6 17001 * [290]11089 ICE: instantiate_virtual_regs_lossage while using SSE 17002 built-ins 17003 * [291]11420 [x86_64] gcc generates invalid asm code when "-O -fPIC" 17004 is used 17005 17006 SPARC- or Solaris- specific 17007 17008 * [292]9362 solaris 'as' dies when fed .s and "-gstabs" 17009 * [293]10142 [SPARC64] gcc produces wrong code when passing 17010 structures by value 17011 * [294]10663 New configure check aborts with Sun tools. 17012 * [295]10835 combinatorial explosion in scheduler on HyperSPARC 17013 * [296]10876 ICE in calculate_giv_inc when building KDE 17014 * [297]10955 wrong code at -O3 for structure argument in context of 17015 structure return 17016 * [298]11018 -mcpu=ultrasparc busts tar-1.13.25 17017 * [299]11556 [sparc64] ICE in gen_reg_rtx() while compiling 2.6.x 17018 Linux kernel 17019 17020 ia64 specific 17021 17022 * [300]10907 gcc violates the ia64 ABI (GP must be preserved) 17023 * [301]11320 scheduler bug (in machine depended reorganization pass) 17024 * [302]11599 bug with conditional and __builtin_prefetch 17025 17026 PowerPC specific 17027 17028 * [303]9745 [powerpc] gcc mis-compiles libmcrypt (alias problem 17029 during loop) 17030 * [304]10871 error in rs6000_stack_info save_size computation 17031 * [305]11440 gcc mis-compiles c++ code (libkhtml) with -O2, -fno-gcse 17032 cures it 17033 17034 m68k-specific 17035 17036 * [306]7594 [m68k] ICE on legal code associated with simplify-rtx 17037 * [307]10557 [m68k] ICE in subreg_offset_representable_p 17038 * [308]11054 [m68k] ICE in reg_overlap_mentioned_p 17039 17040 ARM-specific 17041 17042 * [309]10834 [arm] GCC 3.3 still generates incorrect instructions for 17043 functions with __attribute__ ((interrupt ("IRQ"))) 17044 * [310]10842 [arm] Clobbered link register is copied to pc under 17045 certain circumstances 17046 * [311]11052 [arm] noce_process_if_block() can lose REG_INC notes 17047 * [312]11183 [arm] ICE in change_address_1 (3.3) / subreg_hard_regno 17048 (3.4) 17049 17050 MIPS-specific 17051 17052 * [313]11084 ICE in propagate_one_insn, in flow.c 17053 17054 SH-specific 17055 17056 * [314]10331 can't compile c++ part of gcc cross compiler for sh-elf 17057 * [315]10413 [SH] ICE in reload_cse_simplify_operands, in reload1.c 17058 * [316]11096 i686-linux to sh-linux cross compiler fails to compile 17059 C++ files 17060 17061 GNU/Linux (or Hurd?) specific 17062 17063 * [317]2873 Bogus fixinclude of stdio.h from glibc 2.2.3 17064 17065 UnixWare specific 17066 17067 * [318]3163 configure bug: gcc/aclocal.m4 mmap test fails on UnixWare 17068 7.1.1 17069 17070 Cygwin (or mingw) specific 17071 17072 * [319]5287 ICE with dllimport attribute 17073 * [320]10148 [MingW/CygWin] Compiler dumps core 17074 17075 DJGPP specific 17076 17077 * [321]8787 GCC fails to emit .intel_syntax when invoked with 17078 -masm=intel on DJGPP 17079 17080 Darwin (and MacOS X) specific 17081 17082 * [322]10900 trampolines crash 17083 17084 Documentation 17085 17086 * [323]1607 (c++) Format attributes on methods undocumented 17087 * [324]4252 Invalid option `-fdump-translation-unit' 17088 * [325]4490 Clarify restrictions on -m96bit-long-double, 17089 -m128bit-long-double 17090 * [326]10355 document an issue with regparm attribute on some systems 17091 (e.g. Solaris) 17092 * [327]10726 (fortran) Documentation for function "IDate Intrinsic 17093 (Unix)" is wrong 17094 * [328]10805 document bug in old version of Sun assembler 17095 * [329]10815 warn against GNU binutils on AIX 17096 * [330]10877 document need for newer binutils on i?86-*-linux-gnu 17097 * [331]11280 Manual incorrect with respect to -freorder-blocks 17098 * [332]11466 Document -mlittle-endian and its restrictions for the 17099 sparc64 port 17100 17101 Testsuite bugs (compiler itself is not affected) 17102 17103 * [333]10737 newer bison causes g++.dg/parse/crash2.C to incorrectly 17104 report failure 17105 * [334]10810 gcc-3.3 fails make check: buffer overrun in 17106 test_demangle.c 17107 __________________________________________________________________ 17108 17109 GCC 3.3.2 17110 17111 Bug Fixes 17112 17113 This section lists the problem reports (PRs) from GCC's bug tracker 17114 that are known to be fixed in the 3.3.2 release. This list might not be 17115 complete (that is, it is possible that some PRs that have been fixed 17116 are not listed here). 17117 17118 Bootstrap failures and problems 17119 17120 * [335]8336 [SCO5] bootstrap config still tries to use COFF options 17121 * [336]9330 [alpha-osf] Bootstrap failure on Compaq Tru64 with 17122 --enable-threads=posix 17123 * [337]9631 [hppa64-linux] gcc-3.3 fails to bootstrap 17124 * [338]9877 fixincludes makes a bad sys/byteorder.h on svr5 (UnixWare 17125 7.1.1) 17126 * [339]11687 xstormy16-elf build fails in libf2c 17127 * [340]12263 [SGI IRIX] bootstrap fails during compile of 17128 libf2c/libI77/backspace.c 17129 * [341]12490 buffer overflow in scan-decls.c (during Solaris 9 17130 fix-header processing) 17131 17132 Internal compiler errors (multi-platform) 17133 17134 * [342]7277 Casting integers to vector types causes ICE 17135 * [343]7939 (c++) ICE on invalid function template specialization 17136 * [344]11063 (c++) ICE on parsing initialization list of const array 17137 member 17138 * [345]11207 ICE with negative index in array element designator 17139 * [346]11522 (fortran) g77 dwarf-2 ICE in 17140 add_abstract_origin_attribute 17141 * [347]11595 (c++) ICE on duplicate label definition 17142 * [348]11646 (c++) ICE in commit_one_edge_insertion with 17143 -fnon-call-exceptions -fgcse -O 17144 * [349]11665 ICE in struct initializer when taking address 17145 * [350]11852 (c++) ICE with bad struct initializer. 17146 * [351]11878 (c++) ICE in cp_expr_size 17147 * [352]11883 ICE with any -O on mercury-generated C code 17148 * [353]11991 (c++) ICE in cxx_incomplete_type_diagnostic, in 17149 cp/typeck2.c when applying typeid operator to template template 17150 parameter 17151 * [354]12146 ICE in lookup_template_function, in cp/pt.c 17152 * [355]12215 ICE in make_label_edge with -fnon-call-exceptions 17153 -fno-gcse -O2 17154 * [356]12369 (c++) ICE with templates and friends 17155 * [357]12446 ICE in emit_move_insn on complicated array reference 17156 * [358]12510 ICE in final_scan_insn 17157 * [359]12544 ICE with large parameters used in nested functions 17158 17159 C and optimization bugs 17160 17161 * [360]9862 spurious warnings with -W -finline-functions 17162 * [361]10962 lookup_field is a linear search on a linked list (can be 17163 slow if large struct) 17164 * [362]11370 -Wunreachable-code gives false complaints 17165 * [363]11637 invalid assembly with -fnon-call-exceptions 17166 * [364]11885 Problem with bitfields in packed structs 17167 * [365]12082 Inappropriate unreachable code warnings 17168 * [366]12180 Inline optimization fails for variadic function 17169 * [367]12340 loop unroller + gcse produces wrong code 17170 17171 C++ compiler and library 17172 17173 * [368]3907 nested template parameter collides with member name 17174 * [369]5293 confusing message when binding a temporary to a reference 17175 * [370]5296 [DR115] Pointers to functions and to template functions 17176 behave differently in deduction 17177 * [371]7939 ICE on function template specialization 17178 * [372]8656 Unable to assign function with __attribute__ and pointer 17179 return type to an appropriate variable 17180 * [373]10147 Confusing error message for invalid template function 17181 argument 17182 * [374]11400 std::search_n() makes assumptions about Size parameter 17183 * [375]11409 issues with using declarations, overloading, and 17184 built-in functions 17185 * [376]11740 ctype<wchar_t>::do_is(mask, wchar_t) doesn't handle 17186 multiple bits in mask 17187 * [377]11786 operator() call on variable in other namespace not 17188 recognized 17189 * [378]11867 static_cast ignores ambiguity 17190 * [379]11928 bug with conversion operators that are typedefs 17191 * [380]12114 Uninitialized memory accessed in dtor 17192 * [381]12163 static_cast + explicit constructor regression 17193 * [382]12181 Wrong code with comma operator and c++ 17194 * [383]12236 regparm and fastcall messes up parameters 17195 * [384]12266 incorrect instantiation of unneeded template during 17196 overload resolution 17197 * [385]12296 istream::peek() doesn't set eofbit 17198 * [386]12298 [sjlj exceptions] Stack unwind destroys 17199 not-yet-constructed object 17200 * [387]12369 ICE with templates and friends 17201 * [388]12337 apparently infinite loop in g++ 17202 * [389]12344 stdcall attribute ignored if function returns a pointer 17203 * [390]12451 missing(late) class forward declaration in cxxabi.h 17204 * [391]12486 g++ accepts invalid use of a qualified name 17205 17206 x86 specific (Intel/AMD) 17207 17208 * [392]8869 [x86 MMX] ICE with const variable optimization and MMX 17209 builtins 17210 * [393]9786 ICE in fixup_abnormal_edges with -fnon-call-exceptions 17211 -O2 17212 * [394]11689 g++3.3 emits un-assembleable code for k6 architecture 17213 * [395]12116 [k6] Invalid assembly output values with X-MAME code 17214 * [396]12070 ICE converting between double and long double with 17215 -msoft-float 17216 17217 ia64-specific 17218 17219 * [397]11184 [ia64 hpux] ICE on __builtin_apply building libobjc 17220 * [398]11535 __builtin_return_address may not work on ia64 17221 * [399]11693 [ia64] ICE in gen_nop_type 17222 * [400]12224 [ia64] Thread-local storage doesn't work 17223 17224 PowerPC-specific 17225 17226 * [401]11087 [powerpc64-linux] GCC miscompiles raid1.c from linux 17227 kernel 17228 * [402]11319 loop miscompiled on ppc32 17229 * [403]11949 ICE Compiler segfault with ffmpeg -maltivec code 17230 17231 SPARC-specific 17232 17233 * [404]11662 wrong code for expr. with cast to long long and 17234 exclusive or 17235 * [405]11965 invalid assembler code for a shift < 32 operation 17236 * [406]12301 (c++) stack corruption when a returned expression throws 17237 an exception 17238 17239 Alpha-specific 17240 17241 * [407]11717 [alpha-linux] unrecognizable insn compiling for.c of 17242 kernel 2.4.22-pre8 17243 17244 HPUX-specific 17245 17246 * [408]11313 problem with #pragma weak and static inline functions 17247 * [409]11712 __STDC_EXT__ not defined for C++ by default anymore? 17248 17249 Solaris specific 17250 17251 * [410]12166 Profiled programs crash if PROFDIR is set 17252 17253 Solaris-x86 specific 17254 17255 * [411]12101 i386 Solaris no longer works with GNU as? 17256 17257 Miscellaneous embedded target-specific bugs 17258 17259 * [412]10988 [m32r-elf] wrong blockmove code with -O3 17260 * [413]11805 [h8300-unknown-coff] [H8300] ICE for simple code with 17261 -O2 17262 * [414]11902 [sh4] spec file improperly inserts rpath even when none 17263 needed 17264 * [415]11903 [sh4] -pthread fails to link due to error in spec file 17265 on sh4 17266 __________________________________________________________________ 17267 17268 GCC 3.3.3 17269 17270 Minor features 17271 17272 In addition to the bug fixes documented below, this release contains 17273 few minor features such as: 17274 * Support for --with-sysroot 17275 * Support for automatic detection of executable stacks 17276 * Support for SSE3 instructions 17277 * Support for thread local storage debugging under GDB on S390 17278 17279 Bug Fixes 17280 17281 This section lists the problem reports (PRs) from GCC's bug tracker 17282 that are known to be fixed in the 3.3.3 release. This list might not be 17283 complete (that is, it is possible that some PRs that have been fixed 17284 are not listed here). 17285 17286 Bootstrap failures and issues 17287 17288 * [416]11890 Building cross gcc-3.3.1 for sparc-sun-solaris2.6 fails 17289 * [417]12399 boehm-gc fails (when building a cross compiler): libtool 17290 unable to infer tagged configuration 17291 * [418]13068 mklibgcc.in doesn't handle multi-level multilib 17292 subdirectories properly 17293 17294 Internal compiler errors (multi-platform) 17295 17296 * [419]10060 ICE (stack overflow) on huge file (300k lines) due to 17297 recursive behaviour of copy_rtx_if_shared, in emit_rtl.c 17298 * [420]10555 (c++) ICE on undefined template argument 17299 * [421]10706 (c++) ICE in mangle_class_name_for_template 17300 * [422]11496 (fortran) error in flow_loops_find when -funroll-loops 17301 active 17302 * [423]11741 ICE in pre_insert_copy_insn, in gcse.c 17303 * [424]12440 GCC crashes during compilation of quicktime4linux 2.0.0 17304 * [425]12632 (fortran) -fbounds-check ICE 17305 * [426]12712 (c++) ICE on short legit C++ code fragment with gcc 17306 3.3.2 17307 * [427]12726 (c++) ICE (segfault) on trivial code 17308 * [428]12890 (c++) ICE on compilation of class with throwing method 17309 * [429]12900 (c++) ICE in rtl_verify_flow_info_1 17310 * [430]13060 (fortran) ICE in fixup_var_refs_1, in function.c on 17311 correct code with -O2 -fno-force-mem 17312 * [431]13289 (c++) ICE in regenerate_decl_from_template on recursive 17313 template 17314 * [432]13318 ICE: floating point exception in the loop optimizer 17315 * [433]13392 (c++) ICE in convert_from_eh_region_ranges_1, in 17316 except.c 17317 * [434]13574 (c++) invalid array default initializer in class lets 17318 gcc consume all memory and die 17319 * [435]13475 ICE on SIMD variables with partial value initialization 17320 * [436]13797 (c++) ICE on invalid template parameter 17321 * [437]13824 (java) gcj SEGV with simple .java program 17322 17323 C and optimization bugs 17324 17325 * [438]8776 loop invariants are not removed (most likely) 17326 * [439]10339 [sparc,ppc,ppc64] Invalid optimization: replacing 17327 strncmp by memcmp 17328 * [440]11350 undefined labels with -Os -fPIC 17329 * [441]12826 Optimizer removes reference through volatile pointer 17330 * [442]12500 stabs debug info: void no longer a predefined / builtin 17331 type 17332 * [443]12941 builtin-bitops-1.c miscompilation (latent bug) 17333 * [444]12953 tree inliner bug (in inline_forbidden_p) and fix 17334 * [445]13041 linux-2.6/sound/core/oss/rate.c miscompiled 17335 * [446]13507 spurious printf format warning 17336 * [447]13382 Type information for const pointer disappears during 17337 optimization. 17338 * [448]13394 noreturn attribute ignored on recursive invokation 17339 * [449]13400 Compiled code crashes storing to read-only location 17340 * [450]13521 Endless loop in calculate_global_regs_live 17341 17342 C++ compiler and library 17343 17344 Some of the bug fixes in this list were made to implement decisions 17345 that the ISO C++ standards committee has made concerning several defect 17346 reports (DRs). Links in the list below point to detailed discussion of 17347 the relevant defect report. 17348 * [451]2094 unimplemented: use of `ptrmem_cst' in template type 17349 unification 17350 * [452]2294 using declaration confusion 17351 * [453]5050 template instantiation depth exceeds limit: recursion 17352 problem? 17353 * [454]9371 Bad exception handling in 17354 i/ostream::operator>>/<<(streambuf*) 17355 * [455]9546 bad exception handling in ostream members 17356 * [456]10081 basic_ios::_M_cache_locale leaves NULL members in the 17357 face of unknown locales 17358 * [457]10093 [458][DR 61] Setting failbit in exceptions doesn't work 17359 * [459]10095 istream::operator>>(int&) sets ios::badbit when 17360 ios::failbit is set. 17361 * [460]11554 Warning about reordering of initializers doesn't mention 17362 location of constructor 17363 * [461]12297 istream::sentry::sentry() handles eof() incorrectly. 17364 * [462]12352 Exception safety problems in src/localename.cc 17365 * [463]12438 Memory leak in locale::combine() 17366 * [464]12540 Memory leak in locale::locale(const char*) 17367 * [465]12594 DRs [466]60 [TC] and [467]63 [TC] not implemented 17368 * [468]12657 Resolution of [469]DR 292 (WP) still unimplemented 17369 * [470]12696 memory eating infinite loop in diagnostics (error 17370 recovery problem) 17371 * [471]12815 Code compiled with optimization behaves unexpectedly 17372 * [472]12862 Conflicts between typedefs/enums and namespace member 17373 declarations 17374 * [473]12926 Wrong value after assignment in initialize list using 17375 bit-fields 17376 * [474]12967 Resolution of [475]DR 300 [WP] still unimplemented 17377 * [476]12971 Resolution of [477]DR 328 [WP] still unimplemented 17378 * [478]13007 basic_streambuf::pubimbue, imbue wrong 17379 * [479]13009 Implicitly-defined assignment operator writes to wrong 17380 memory 17381 * [480]13057 regparm attribute not applied to destructor 17382 * [481]13070 -Wformat option ignored in g++ 17383 * [482]13081 forward template declarations in <complex> let inlining 17384 fail 17385 * [483]13239 Assertion does not seem to work correctly anymore 17386 * [484]13262 "xxx is private within this context" when initializing a 17387 self-contained template class 17388 * [485]13290 simple typo in concept checking for std::generate_n 17389 * [486]13323 Template code does not compile in presence of typedef 17390 * [487]13369 __verify_grouping (and __add_grouping?) not correct 17391 * [488]13371 infinite loop with packed struct and inlining 17392 * [489]13445 Template argument replacement "dereferences" a typedef 17393 * [490]13461 Fails to access protected-ctor from public constant 17394 * [491]13462 Non-standard-conforming type set::pointer 17395 * [492]13478 gcc uses wrong constructor to initialize a const 17396 reference 17397 * [493]13544 "conflicting types" for enums in different scopes 17398 * [494]13650 string::compare should not (always) use 17399 traits_type::length() 17400 * [495]13683 bogus warning about passing non-PODs through ellipsis 17401 * [496]13688 Derived class is denied access to protected base class 17402 member class 17403 * [497]13774 Member variable cleared in virtual multiple inheritance 17404 class 17405 * [498]13884 Protect sstream.tcc from extern template use 17406 17407 Java compiler and library 17408 17409 * [499]10746 [win32] garbage collection crash in GCJ 17410 17411 Objective-C compiler and library 17412 17413 * [500]11433 Crash due to dereferencing null pointer when querying 17414 protocol 17415 17416 Fortran compiler and library 17417 17418 * [501]12633 logical expression gives incorrect result with 17419 -fugly-logint option 17420 * [502]13037 [gcse-lm] g77 generates incorrect code 17421 * [503]13213 Hex constant problem when compiling with -fugly-logint 17422 and -ftypeless-boz 17423 17424 x86-specific (Intel/AMD) 17425 17426 * [504]4490 ICE with -m128bit-long-double 17427 * [505]12292 [x86_64] ICE: RTL check: expected code `const_int', have 17428 `reg' in make_field_assignment, in combine.c 17429 * [506]12441 ICE: can't find a register to spill 17430 * [507]12943 array static-init failure under -fpic, -fPIC 17431 * [508]13608 Incorrect code with -O3 -ffast-math 17432 17433 PowerPC-specific 17434 17435 * [509]11598 testcase gcc.dg/20020118-1.c fails runtime check of 17436 __attribute__((aligned(16))) 17437 * [510]11793 ICE in extract_insn, in recog.c (const_vector's) 17438 * [511]12467 vmsumubm emitted when vmsummbm appropriate (typo in 17439 altivec.md) 17440 * [512]12537 g++ generates writeable text sections 17441 17442 SPARC-specific 17443 17444 * [513]12496 wrong result for __atomic_add(&value, -1) when using -O0 17445 -m64 17446 * [514]12865 mprotect call to make trampoline executable may fail 17447 * [515]13354 ICE in sparc_emit_set_const32 17448 17449 ARM-specific 17450 17451 * [516]10467 [arm] ICE in pre_insert_copy_insn, 17452 17453 ia64-specific 17454 17455 * [517]11226 ICE passing struct arg with two floats 17456 * [518]11227 ICE for _Complex float, _Complex long double args 17457 * [519]12644 GCC 3.3.2 fails to compile glibc on ia64 17458 * [520]13149 build gcc-3.3.2 1305 error:unrecognizable insn 17459 * Various fixes for libunwind 17460 17461 Alpha-specific 17462 17463 * [521]12654 Incorrect comparison code generated for Alpha 17464 * [522]12965 SEGV+ICE in cc1plus on alpha-linux with -O2 17465 * [523]13031 ICE (unrecognizable insn) when building gnome-libs-1.4.2 17466 17467 HPPA-specific 17468 17469 * [524]11634 [hppa] ICE in verify_local_live_at_start, in flow.c 17470 * [525]12158 [hppa] compilation does not terminate at -O1 17471 17472 S390-specific 17473 17474 * [526]11992 Wrong built-in code for memcmp with length 1<<24: only 17475 (1<<24)-1 possible for CLCL-Instruction 17476 17477 SH-specific 17478 17479 * [527]9365 segfault in gen_far_branch (config/sh/sh.c) 17480 * [528]10392 optimizer generates faulty array indexing 17481 * [529]11322 SH profiler outputs multiple definitions of symbol 17482 * [530]13069 gcc/config/sh/rtems.h broken 17483 * [531]13302 Putting a va_list in a struct causes seg fault 17484 * [532]13585 Incorrect optimization of call to sfunc 17485 * Fix inappropriately exported libgcc functions from the shared 17486 library 17487 17488 Other embedded target specific 17489 17490 * [533]8916 [mcore] unsigned char assign gets hosed. 17491 * [534]11576 [h8300] ICE in change_address_1, in emit-rtl.c 17492 * [535]13122 [h8300] local variable gets corrupted by function call 17493 when -fomit-frame-pointer is given 17494 * [536]13256 [cris] strict_low_part mistreated in delay slots 17495 * [537]13373 [mcore] optimization with -frerun-cse-after-loop 17496 -fexpensive-optimizations produces wrong code on mcore 17497 17498 GNU HURD-specific 17499 17500 * [538]12561 gcc/config/t-gnu needs updating to work with 17501 --with-sysroot 17502 17503 Tru64 Unix specific 17504 17505 * [539]6243 testsuite fails almost all tests due to no libintl in 17506 LD_LIBRARY_PATH during test. 17507 * [540]11397 weak aliases broken on Tru64 UNIX 17508 17509 AIX-specific 17510 17511 * [541]12505 build failure due to defines of uchar in cpphash.h and 17512 sys/types.h 17513 * [542]13150 WEAK symbols not exported by collect2 17514 17515 IRIX-specific 17516 17517 * [543]12666 fixincludes problem on IRIX 6.5.19m 17518 17519 Solaris-specific 17520 17521 * [544]12969 Including sys/byteorder.h breaks configure checks 17522 17523 Testsuite problems (compiler is not affected) 17524 17525 * [545]10819 testsuite creates CR+LF on compiler version lines in 17526 test summary files 17527 * [546]11612 abi_check not finding correct libgcc_s.so.1 17528 17529 Miscellaneous 17530 17531 * [547]13211 using -###, incorrect warnings about unused linker file 17532 are produced 17533 __________________________________________________________________ 17534 17535 GCC 3.3.4 17536 17537 This is the [548]list of problem reports (PRs) from GCC's bug tracking 17538 system that are known to be fixed in the 3.3.4 release. This list might 17539 not be complete (that is, it is possible that some PRs that have been 17540 fixed are not listed here). 17541 __________________________________________________________________ 17542 17543 GCC 3.3.5 17544 17545 This is the [549]list of problem reports (PRs) from GCC's bug tracking 17546 system that are known to be fixed in the 3.3.5 release. This list might 17547 not be complete (that is, it is possible that some PRs that have been 17548 fixed are not listed here). 17549 __________________________________________________________________ 17550 17551 GCC 3.3.6 17552 17553 This is the [550]list of problem reports (PRs) from GCC's bug tracking 17554 system that are known to be fixed in the 3.3.6 release. This list might 17555 not be complete (that is, it is possible that some PRs that have been 17556 fixed are not listed here). 17557 17558 17559 For questions related to the use of GCC, please consult these web 17560 pages and the [551]GCC manuals. If that fails, the 17561 [552]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 17562 web pages and the development of GCC are welcome on our developer 17563 list at [553]gcc (a] gcc.gnu.org. All of [554]our lists have public 17564 archives. 17565 17566 Copyright (C) [555]Free Software Foundation, Inc. Verbatim copying and 17567 distribution of this entire article is permitted in any medium, 17568 provided this notice is preserved. 17569 17570 These pages are [556]maintained by the GCC team. Last modified 17571 2023-01-19. 17572 17573 References 17574 17575 1. http://gcc.gnu.org/gcc-3.3/changes.html#3.3.6 17576 2. http://gcc.gnu.org/gcc-3.1/changes.html#obsolete_systems 17577 3. http://gcc.gnu.org/gcc-3.3/changes.html#obsolete_systems 17578 4. http://gcc.gnu.org/gcc-3.3/changes.html#nonnull_attribute 17579 5. http://gcc.gnu.org/news/dfa.html 17580 6. http://gcc.gnu.org/c99status.html 17581 7. https://gcc.gnu.org/onlinedocs/gcc-3.3.6/g77/News.html 17582 8. https://gcc.gnu.org/PR10140 17583 9. https://gcc.gnu.org/PR10198 17584 10. https://gcc.gnu.org/PR10338 17585 11. https://gcc.gnu.org/PR3581 17586 12. https://gcc.gnu.org/PR4382 17587 13. https://gcc.gnu.org/PR5533 17588 14. https://gcc.gnu.org/PR6387 17589 15. https://gcc.gnu.org/PR6412 17590 16. https://gcc.gnu.org/PR6620 17591 17. https://gcc.gnu.org/PR6663 17592 18. https://gcc.gnu.org/PR7068 17593 19. https://gcc.gnu.org/PR7083 17594 20. https://gcc.gnu.org/PR7647 17595 21. https://gcc.gnu.org/PR7675 17596 22. https://gcc.gnu.org/PR7718 17597 23. https://gcc.gnu.org/PR8116 17598 24. https://gcc.gnu.org/PR8358 17599 25. https://gcc.gnu.org/PR8511 17600 26. https://gcc.gnu.org/PR8564 17601 27. https://gcc.gnu.org/PR8660 17602 28. https://gcc.gnu.org/PR8766 17603 29. https://gcc.gnu.org/PR8803 17604 30. https://gcc.gnu.org/PR8846 17605 31. https://gcc.gnu.org/PR8906 17606 32. https://gcc.gnu.org/PR9216 17607 33. https://gcc.gnu.org/PR9261 17608 34. https://gcc.gnu.org/PR9263 17609 35. https://gcc.gnu.org/PR9429 17610 36. https://gcc.gnu.org/PR9516 17611 37. https://gcc.gnu.org/PR9600 17612 38. https://gcc.gnu.org/PR9629 17613 39. https://gcc.gnu.org/PR9672 17614 40. https://gcc.gnu.org/PR9749 17615 41. https://gcc.gnu.org/PR9794 17616 42. https://gcc.gnu.org/PR9829 17617 43. https://gcc.gnu.org/PR9916 17618 44. https://gcc.gnu.org/PR9936 17619 45. https://gcc.gnu.org/PR10262 17620 46. https://gcc.gnu.org/PR10278 17621 47. https://gcc.gnu.org/PR10446 17622 48. https://gcc.gnu.org/PR10451 17623 49. https://gcc.gnu.org/PR10506 17624 50. https://gcc.gnu.org/PR10549 17625 51. https://gcc.gnu.org/PR2001 17626 52. https://gcc.gnu.org/PR2391 17627 53. https://gcc.gnu.org/PR2960 17628 54. https://gcc.gnu.org/PR4046 17629 55. https://gcc.gnu.org/PR6405 17630 56. https://gcc.gnu.org/PR6798 17631 57. https://gcc.gnu.org/PR6871 17632 58. https://gcc.gnu.org/PR6909 17633 59. https://gcc.gnu.org/PR7189 17634 60. https://gcc.gnu.org/PR7642 17635 61. https://gcc.gnu.org/PR8634 17636 62. https://gcc.gnu.org/PR8750 17637 63. https://gcc.gnu.org/PR2161 17638 64. https://gcc.gnu.org/PR4319 17639 65. https://gcc.gnu.org/PR8602 17640 66. https://gcc.gnu.org/PR9177 17641 67. https://gcc.gnu.org/PR9853 17642 68. https://gcc.gnu.org/PR45 17643 69. https://gcc.gnu.org/PR3784 17644 70. https://gcc.gnu.org/PR764 17645 71. https://gcc.gnu.org/PR5116 17646 72. https://gcc.gnu.org/PR2862 17647 73. https://gcc.gnu.org/PR3663 17648 74. https://gcc.gnu.org/PR3797 17649 75. https://gcc.gnu.org/PR3948 17650 76. https://gcc.gnu.org/PR4137 17651 77. https://gcc.gnu.org/PR4361 17652 78. https://gcc.gnu.org/PR4802 17653 79. https://gcc.gnu.org/PR5837 17654 80. https://gcc.gnu.org/PR4803 17655 81. https://gcc.gnu.org/PR5094 17656 82. https://gcc.gnu.org/PR5730 17657 83. https://gcc.gnu.org/PR6713 17658 84. https://gcc.gnu.org/PR7015 17659 85. https://gcc.gnu.org/PR7086 17660 86. https://gcc.gnu.org/PR7099 17661 87. https://gcc.gnu.org/PR7247 17662 88. https://gcc.gnu.org/PR7441 17663 89. https://gcc.gnu.org/PR7768 17664 90. https://gcc.gnu.org/PR7804 17665 91. https://gcc.gnu.org/PR8099 17666 92. https://gcc.gnu.org/PR8117 17667 93. https://gcc.gnu.org/PR8205 17668 94. https://gcc.gnu.org/PR8645 17669 95. https://gcc.gnu.org/PR8724 17670 96. https://gcc.gnu.org/PR8805 17671 97. https://gcc.gnu.org/PR8691 17672 98. https://gcc.gnu.org/PR8700 17673 99. https://gcc.gnu.org/PR8724 17674 100. https://gcc.gnu.org/PR8949 17675 101. https://gcc.gnu.org/PR9016 17676 102. https://gcc.gnu.org/PR9053 17677 103. https://gcc.gnu.org/PR9152 17678 104. https://gcc.gnu.org/PR9182 17679 105. https://gcc.gnu.org/PR9297 17680 106. https://gcc.gnu.org/PR9318 17681 107. https://gcc.gnu.org/PR9320 17682 108. https://gcc.gnu.org/PR9400 17683 109. https://gcc.gnu.org/PR9424 17684 110. https://gcc.gnu.org/PR9425 17685 111. https://gcc.gnu.org/PR9439 17686 112. https://gcc.gnu.org/PR9474 17687 113. https://gcc.gnu.org/PR9548 17688 114. https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#231 17689 115. https://gcc.gnu.org/PR9555 17690 116. https://gcc.gnu.org/PR9561 17691 117. https://gcc.gnu.org/PR9563 17692 118. https://gcc.gnu.org/PR9582 17693 119. https://gcc.gnu.org/PR9622 17694 120. https://gcc.gnu.org/PR9683 17695 121. https://gcc.gnu.org/PR9791 17696 122. https://gcc.gnu.org/PR9817 17697 123. https://gcc.gnu.org/PR9825 17698 124. https://gcc.gnu.org/PR9826 17699 125. https://gcc.gnu.org/PR9924 17700 126. https://gcc.gnu.org/PR9946 17701 127. https://gcc.gnu.org/PR9964 17702 128. https://gcc.gnu.org/PR9988 17703 129. https://gcc.gnu.org/PR10033 17704 130. https://gcc.gnu.org/PR10097 17705 131. https://gcc.gnu.org/PR10132 17706 132. https://gcc.gnu.org/PR10180 17707 133. https://gcc.gnu.org/PR10199 17708 134. https://gcc.gnu.org/PR10300 17709 135. https://gcc.gnu.org/PR10427 17710 136. https://gcc.gnu.org/PR10503 17711 137. https://gcc.gnu.org/PR5956 17712 138. https://gcc.gnu.org/PR1832 17713 139. https://gcc.gnu.org/PR3924 17714 140. https://gcc.gnu.org/PR5634 17715 141. https://gcc.gnu.org/PR6367 17716 142. https://gcc.gnu.org/PR6491 17717 143. https://gcc.gnu.org/PR6742 17718 144. https://gcc.gnu.org/PR7113 17719 145. https://gcc.gnu.org/PR7236 17720 146. https://gcc.gnu.org/PR7278 17721 147. https://gcc.gnu.org/PR7384 17722 148. https://gcc.gnu.org/PR7388 17723 149. https://gcc.gnu.org/PR8587 17724 150. https://gcc.gnu.org/PR9038 17725 151. https://gcc.gnu.org/PR10197 17726 152. https://gcc.gnu.org/PR6005 17727 153. https://gcc.gnu.org/PR6389 17728 154. 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https://gcc.gnu.org/onlinedocs/ 18126 552. mailto:gcc-help (a] gcc.gnu.org 18127 553. mailto:gcc (a] gcc.gnu.org 18128 554. https://gcc.gnu.org/lists.html 18129 555. https://www.fsf.org/ 18130 556. https://gcc.gnu.org/about.html 18131 ====================================================================== 18132 http://gcc.gnu.org/gcc-3.2/index.html 18133 18134 GCC 3.2 Release Series 18135 18136 (This release series is no longer supported.) 18137 18138 April 25, 2003 18139 18140 The [1]GNU project and the GCC developers are pleased to announce the 18141 release of GCC 3.2.3. 18142 18143 The purpose of the GCC 3.2 release series is to provide a stable 18144 platform for OS distributors to use building their next releases. A 18145 primary objective was to stabilize the C++ ABI; we believe that the 18146 interface to the compiler and the C++ standard library are now 18147 relatively stable. 18148 18149 Be aware that C++ code compiled by GCC 3.2.x will (in general) not 18150 interoperate with code compiled by GCC 3.1.1 or earlier. 18151 18152 Please refer to our [2]detailed list of news, caveats, and bug-fixes 18153 for further information. 18154 18155 Release History 18156 18157 GCC 3.2.3 18158 April 25, 2003 ([3]changes) 18159 18160 GCC 3.2.2 18161 February 5, 2003 ([4]changes) 18162 18163 GCC 3.2.1 18164 November 19, 2002 ([5]changes) 18165 18166 GCC 3.2 18167 August 14, 2002 ([6]changes) 18168 18169 References and Acknowledgements 18170 18171 GCC used to stand for the GNU C Compiler, but since the compiler 18172 supports several other languages aside from C, it now stands for the 18173 GNU Compiler Collection. 18174 18175 A list of [7]successful builds is updated as new information becomes 18176 available. 18177 18178 The GCC developers would like to thank the numerous people that have 18179 contributed new features, improvements, bug fixes, and other changes as 18180 well as test results to GCC. This [8]amazing group of volunteers is 18181 what makes GCC successful. 18182 18183 For additional information about GCC please refer to the [9]GCC project 18184 web site or contact the [10]GCC development mailing list. 18185 18186 To obtain GCC please use [11]our mirror sites, or our CVS server. 18187 18188 18189 For questions related to the use of GCC, please consult these web 18190 pages and the [12]GCC manuals. If that fails, the 18191 [13]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 18192 web pages and the development of GCC are welcome on our developer 18193 list at [14]gcc (a] gcc.gnu.org. All of [15]our lists have public 18194 archives. 18195 18196 Copyright (C) [16]Free Software Foundation, Inc. Verbatim copying and 18197 distribution of this entire article is permitted in any medium, 18198 provided this notice is preserved. 18199 18200 These pages are [17]maintained by the GCC team. Last modified 18201 2022-10-26. 18202 18203 References 18204 18205 1. http://www.gnu.org/ 18206 2. http://gcc.gnu.org/gcc-3.2/changes.html 18207 3. http://gcc.gnu.org/gcc-3.2/changes.html#3.2.3 18208 4. http://gcc.gnu.org/gcc-3.2/changes.html#3.2.2 18209 5. http://gcc.gnu.org/gcc-3.2/changes.html#3.2.1 18210 6. http://gcc.gnu.org/gcc-3.2/changes.html#3.2 18211 7. http://gcc.gnu.org/gcc-3.2/buildstat.html 18212 8. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 18213 9. http://gcc.gnu.org/index.html 18214 10. mailto:gcc (a] gcc.gnu.org 18215 11. http://gcc.gnu.org/mirrors.html 18216 12. https://gcc.gnu.org/onlinedocs/ 18217 13. mailto:gcc-help (a] gcc.gnu.org 18218 14. mailto:gcc (a] gcc.gnu.org 18219 15. https://gcc.gnu.org/lists.html 18220 16. https://www.fsf.org/ 18221 17. https://gcc.gnu.org/about.html 18222 ====================================================================== 18223 http://gcc.gnu.org/gcc-3.2/changes.html 18224 18225 GCC 3.2 Release Series 18226 Changes, New Features, and Fixes 18227 18228 The latest release in the 3.2 release series is [1]GCC 3.2.3. 18229 18230 Caveats and New Features 18231 18232 Caveats 18233 18234 * The C++ compiler does not correctly zero-initialize 18235 pointers-to-data members. You must explicitly initialize them. For 18236 example: int S::*m(0); will work, but depending on 18237 default-initialization to zero will not work. This bug cannot be 18238 fixed in GCC 3.2 without inducing unacceptable risks. It will be 18239 fixed in GCC 3.3. 18240 * This GCC release is based on the GCC 3.1 sourcebase, and thus has 18241 all the [2]changes in the GCC 3.1 series. In addition, GCC 3.2 has 18242 a number of C++ ABI fixes which make its C++ compiler generate 18243 binary code which is incompatible with the C++ compilers found in 18244 earlier GCC releases, including GCC 3.1 and GCC 3.1.1. 18245 18246 Frontend Enhancements 18247 18248 C/C++/Objective-C 18249 18250 * The method of constructing the list of directories to be searched 18251 for header files has been revised. If a directory named by a -I 18252 option is a standard system include directory, the option is 18253 ignored to ensure that the default search order for system 18254 directories and the special treatment of system header files are 18255 not defeated. 18256 * The C and Objective-C compilers no longer accept the "Naming Types" 18257 extension (typedef foo = bar); it was already unavailable in C++. 18258 Code which uses it will need to be changed to use the "typeof" 18259 extension instead: typedef typeof(bar) foo. (We have removed this 18260 extension without a period of deprecation because it has caused the 18261 compiler to crash since version 3.0 and no one noticed until very 18262 recently. Thus we conclude it is not in widespread use.) 18263 18264 C++ 18265 18266 * GCC 3.2 fixed serveral differences between the C++ ABI implemented 18267 in GCC and the multi-vendor standard, but more have been found 18268 since the release. 3.2.1 adds a new warning, -Wabi, to warn about 18269 code which is affected by these bugs. We will fix these bugs in 18270 some future release, once we are confident that all have been 18271 found; until then, it is our intention to make changes to the ABI 18272 only if they are necessary for correct compilation of C++, as 18273 opposed to conformance to the ABI documents. 18274 * For details on how to build an ABI compliant compiler for GNU/Linux 18275 systems, check the [3]common C++ ABI page. 18276 18277 New Targets and Target Specific Improvements 18278 18279 IA-32 18280 18281 * Fixed a number of bugs in SSE and MMX intrinsics. 18282 * Fixed common compiler crashes with SSE instruction set enabled 18283 (implied by -march=pentium3, pentium4, athlon-xp) 18284 * __m128 and __m128i is not 128bit aligned when used in structures. 18285 18286 x86-64 18287 18288 * A bug whereby the compiler could generate bad code for bzero has 18289 been fixed. 18290 * ABI fixes (implying ABI incompatibilities with previous version in 18291 some corner cases) 18292 * Fixed prefetch code generation 18293 __________________________________________________________________ 18294 18295 GCC 3.2.3 18296 18297 3.2.3 is a bug fix release only; there are no new features that were 18298 not present in GCC 3.2.2. 18299 18300 Bug Fixes 18301 18302 This section lists the problem reports (PRs) from GCC's bug tracking 18303 system that are known to be fixed in the 3.2.3 release. This list might 18304 not be complete (that is, it is possible that some PRs that have been 18305 fixed are not listed here), and some of the titles have been changed to 18306 make them more clear. 18307 18308 Internal Compiler Errors (multi-platform) 18309 18310 * [4]3782: (c++) -quiet -fstats produces a segmentation fault in 18311 cc1plus 18312 * [5]6440: (c++) template specializations cause ICE 18313 * [6]7050: (c++) ICE on: (i ? get_string() : throw) 18314 * [7]7741: ICE on conflicting types (make_decl_rtl in varasm.c) 18315 * [8]7982: (c++) ICE due to infinite recursion (using STL set) 18316 * [9]8068: exceedingly high (infinite) memory usage 18317 * [10]8178: ICE with __builtin_ffs 18318 * [11]8396: ICE in copy_to_mode_reg, in explow.c 18319 * [12]8674: (c++) ICE in cp_expr_size, in cp/cp-lang.c 18320 * [13]9768: ICE when optimizing inline code at -O2 18321 * [14]9798: (c++) Infinite recursion (segfault) in 18322 cp/decl.c:push_using_directive with recursive using directives 18323 * [15]9799: mismatching structure initializer with nested flexible 18324 array member: ICE 18325 * [16]9928: ICE on duplicate enum declaration 18326 * [17]10114: ICE in mem_loc_descriptor, in dwarf2out.c (affects 18327 sparc, alpha) 18328 * [18]10352: ICE in find_reloads_toplev 18329 * [19]10336: ICE with -Wunreachable-code 18330 18331 C/optimizer bugs: 18332 18333 * [20]8224: Incorrect joining of signed and unsigned division 18334 * [21]8613: -O2 produces wrong code with builtin strlen and 18335 postincrements 18336 * [22]8828: gcc reports some code is unreachable when it is not 18337 * [23]9226: GCSE breaking argument passing 18338 * [24]9853: miscompilation of non-constant structure initializer 18339 * [25]9797: C99-style struct initializers are miscompiled 18340 * [26]9967: Some standard C function calls should not be replaced 18341 when optimizing for size 18342 * [27]10116: ce2: invalid merge of join_bb in the context of switch 18343 statements 18344 * [28]10171: wrong code for inlined function 18345 * [29]10175: -Wunreachable-code doesn't work for single lines 18346 18347 C++ compiler and library: 18348 18349 * [30]8316: Confusing diagnostic for code that misuses conversion 18350 operators 18351 * [31]9169: filebuf output fails if codecvt<>::out returns noconv 18352 * [32]9420: incomplete type incorrectly reported 18353 * [33]9459: typeof in return type specification of template not 18354 supported 18355 * [34]9507: filebuf::open handles ios_base::ate incorrectly 18356 * [35]9538: Out-of-bounds memory access in streambuf::sputbackc 18357 * [36]9602: Total confusion about template/friend/virtual/abstract 18358 * [37]9993: destructor not called for local object created within and 18359 returned from infinite loop 18360 * [38]10167: ieee_1003.1-2001 locale specialisations on a glibc-2.3.2 18361 system 18362 18363 Java compiler and library: 18364 18365 * [39]9652: libgcj build fails on irix6.5.1[78] 18366 * [40]10144: gas on solaris complains about bad .stabs lines for 18367 java, native as unaffected 18368 18369 x86-specific (Intel/AMD): 18370 18371 * [41]8746: gcc miscompiles Linux kernel ppa driver on x86 18372 * [42]9888: -mcpu=k6 -Os produces out of range loop instructions 18373 * [43]9638: Cross-build for target i386-elf and i586-pc-linux-gnu 18374 failed 18375 * [44]9954: Cross-build for target i586-pc-linux-gnu (--with-newlib) 18376 failed 18377 18378 SPARC-specific: 18379 18380 * [45]7784: [Sparc] ICE in extract_insn, in recog.c 18381 * [46]7796: sparc extra failure with -m64 on execute/930921-1.c in 18382 unroll.c 18383 * [47]8281: ICE when compiling with -O2 -fPIC for Ultrasparc 18384 * [48]8366: [Sparc] C testsuite failure with -m64 -fpic -O in 18385 execute/loop-2d.c 18386 * [49]8726: gcc -O2 miscompiles Samba 2.2.7 on 32-bit sparc 18387 * [50]9414: Scheduling bug on Ultrasparc 18388 * [51]10067: GCC-3.2.2 outputs invalid asm on sparc64 18389 18390 m68k-specific: 18391 18392 * [52]7248: broken "inclusive or" code 18393 * [53]8343: m68k-elf/rtems ICE at instantiate_virtual_regs_1 18394 18395 PowerPC-specific: 18396 18397 * [54]9732: Wrong code with -O2 -fPIC 18398 * [55]10073: ICE: powerpc cannot split insn 18399 18400 Alpha-specific: 18401 18402 * [56]7702: optimization problem on a DEC alpha under OSF1 18403 * [57]9671: gcc.3.2.2 does not build on a HP Tru64 Unix v5.1B system 18404 18405 HP-specific: 18406 18407 * [58]8694: <string> breaks <ctype.h> on HP-UX 10.20 (DUP: 9275) 18408 * [59]9953: (ada) gcc 3.2.x can't build 3.3-branch ada on HP-UX 10 18409 (missing symbol) 18410 * [60]10271: Floating point args don't get reloaded across function 18411 calls with -O2 18412 18413 MIPS specific: 18414 18415 * [61]6362: mips-irix6 gcc-3.1 C testsuite failure with -mips4 in 18416 compile/920501-4.c 18417 18418 CRIS specific: 18419 18420 * [62]10377: gcc-3.2.2 creates bad assembler code for cris 18421 18422 Miscellaneous and minor bugs: 18423 18424 * [63]6955: collect2 says "core dumped" when there is no core 18425 __________________________________________________________________ 18426 18427 GCC 3.2.2 18428 18429 Beginning with 3.2.2, GCC's Makefile suite supports redirection of make 18430 install by means of the DESTDIR variable. Parts of the GCC tree have 18431 featured that support long before, but now it is available even from 18432 the top level. 18433 18434 Other than that, GCC 3.2.2 is a bug fix release only; there are no new 18435 features that were not present in GCC 3.2.1. 18436 18437 Bug Fixes 18438 18439 On the following i386-based systems GCC 3.2.1 broke the C ABI wrt. 18440 functions returning structures: Cygwin, FreeBSD (GCC 3.2.1 as shipped 18441 with FreeBSD 5.0 does not have this problem), Interix, a.out-based 18442 GNU/Linux and NetBSD, OpenBSD, and Darwin. GCC 3.2.2 reverts this ABI 18443 change, and thus restores ABI-compatibility with previous releases 18444 (except GCC 3.2.1) on these platforms. 18445 18446 This section lists the problem reports (PRs) from GCC's bug tracking 18447 system that are known to be fixed in the 3.2.2 release. This list might 18448 not be complete (that is, it is possible that some PRs that have been 18449 fixed are not listed here) and some of the titles have been changed to 18450 make them more clear. 18451 18452 Internal Compiler Errors (multi-platform) 18453 18454 * [64]5919: (c++) ICE when passing variable array to template 18455 function 18456 * [65]7129: (c++) ICE with min/max assignment operators (<?= and >?=) 18457 * [66]7507: ICE with -O2 when address of called function is a 18458 complicated expression 18459 * [67]7622: ICE with nested inline functions if function's address is 18460 taken 18461 * [68]7681: (fortran) ICE in compensate_edge, in reg-stack.c (also PR 18462 [69]9258) 18463 * [70]8031: (c++) ICE in code comparing typeids and casting from 18464 virtual base 18465 * [71]8275: ICE in simplify_subreg 18466 * [72]8332: (c++) builtin strlen/template interaction causes ICE 18467 * [73]8372: (c++) ICE on explicit call of destructor 18468 * [74]8439: (c, not c++) empty struct causes ICE 18469 * [75]8442: (c++) ICE with nested template classes 18470 * [76]8518: ICE when compiling mplayer ("extern inline" issue) 18471 * [77]8615: (c++) ICE with out-of-range character constant template 18472 argument 18473 * [78]8663: (c++) ICE in cp_expr_size, at cp-lang.c:307 18474 * [79]8799: (c++) ICE: error reporting routines re-entered 18475 * [80]9328: (c++) ICE with typeof(X) for overloaded X 18476 * [81]9465: (preprocessor) cpp -traditional ICE on null bytes 18477 18478 C++ (compiler and library) bugs 18479 18480 * [82]47: scoping in nested classes is broken 18481 * [83]6745: problems with iostream rdbuf() member function 18482 * [84]8214: conversion from const char* const to char* sometimes 18483 accepted illegally 18484 * [85]8493: builtin strlen and overload resolution (same bug as 18485 [86]8332) 18486 * [87]8503: strange behaviour of function types 18487 * [88]8727: compiler confused by inheritance from an anonymous struct 18488 * [89]7445: poor performance of std::locale::classic() in 18489 multi-threaded applications 18490 * [90]8230: mishandling of overflow in vector<T>::resize 18491 * [91]8399: sync_with_stdio(false) breaks unformatted input 18492 * [92]8662: illegal access of private member of unnamed class is 18493 accepted 18494 * [93]8707: "make distclean" fails in libstdc++-v3 directory 18495 * [94]8708: __USE_MALLOC doesn't work 18496 * [95]8790: Use of non-thread-safe strtok in src/localename.cc 18497 * [96]8887: Bug in date formats with --enable-clocale=generic 18498 * [97]9076: Call Frame Instructions are not handled correctly during 18499 unwind operation 18500 * [98]9151: std::setprecision limited to 16 digits when outputting a 18501 double to a stream 18502 * [99]9168: codecvt<char, char, mbstate_t> overwrites output buffers 18503 * [100]9269: libstdc++ headers: explicit specialization of function 18504 must precede its first use 18505 * [101]9322: return value of basic_streambuf<>::getloc affected by 18506 locale::global 18507 * [102]9433: segfault in runtime support for dynamic_cast 18508 18509 C and optimizer bugs 18510 18511 * [103]8032: GCC incorrectly initializes static structs that have 18512 flexible arrays 18513 * [104]8639: simple arithmetic expression broken 18514 * [105]8794: optimization improperly eliminates certain expressions 18515 * [106]8832: traditional "asm volatile" code is illegally optimized 18516 * [107]8988: loop optimizer bug: with -O2, code is generated that 18517 segfaults (found on i386, bug present for all platforms) 18518 * [108]9492: structure copy clobbers subsequent stores to structure 18519 18520 Objective-C bugs 18521 18522 * [109]9267: Objective-C parser won't build with newer bison versions 18523 (e.g. 1.875) 18524 18525 Ada bugs 18526 18527 * [110]8344: Ada build problem due to conflict between gcc/final.o, 18528 gcc/ada/final.o 18529 18530 Preprocessor bugs 18531 18532 * [111]8524: _Pragma within macros is improperly expanded 18533 * [112]8880: __WCHAR_TYPE__ macro incorrectly set to "long int" with 18534 -fshort-wchar 18535 18536 ARM-specific 18537 18538 * [113]9090: arm ICE with >= -O2; regression from gcc-2.95 18539 18540 x86-specific (Intel/AMD) 18541 18542 * [114]8588: ICE in extract_insn, at recog.c:NNNN (shift instruction) 18543 * [115]8599: loop unroll bug with -march=k6-3 18544 * [116]9506: ABI breakage in structure return (affects BSD and 18545 Cygwin, but not GNU/Linux) 18546 18547 FreeBSD 5.0 specific 18548 18549 * [117]9484: GCC 3.2.1 Bootstrap failure on FreeBSD 5.0 18550 18551 RTEMS-specific 18552 18553 * [118]9292: hppa1.1-rtems configurery problems 18554 * [119]9293: [m68k-elf/rtems] config/m68k/t-crtstuff bug 18555 * [120]9295: [mips-rtems] config/mips/rtems.h init/fini issue 18556 * [121]9296: gthr-rtems regression 18557 * [122]9316: powerpc-rtems: extending multilibs 18558 18559 HP-PA specific 18560 18561 * [123]9493: ICE with -O2 when building a simple function 18562 18563 Documentation 18564 18565 * [124]7341: hyperlink to gcov in GCC documentation doesn't work 18566 * [125]8947: Please add a warning about "-malign-double" in docs 18567 * [126]7448, [127]8882: typo cleanups 18568 __________________________________________________________________ 18569 18570 GCC 3.2.1 18571 18572 3.2.1 adds a new warning, -Wabi. This option warns when GNU C++ 18573 generates code that is known not to be binary-compatible with the 18574 vendor-neutral ia32/ia64 ABI. Please consult the GCC manual, included 18575 in the distribution, for details. 18576 18577 This release also removes an old GCC extension, "naming types", and the 18578 documentation now directs users to use a different GCC extension, 18579 __typeof__, instead. The feature had evidently been broken for a while. 18580 18581 Otherwise, 3.2.1 is a bug fix release only; other than bug fixes and 18582 the new warning there are no new features that were not present in GCC 18583 3.2. 18584 18585 In addition, the previous fix for [128]PR 7445 (poor performance of 18586 std::locale::classic() in multi-threaded applications) was reverted 18587 ("unfixed"), because the "fix" was not thread-safe. 18588 18589 Bug Fixes 18590 18591 This section lists the problem reports (PRs) from GCC's bug tracking 18592 system that are known to be fixed in the 3.2.1 release. This list might 18593 not be complete (that is, it is possible that some PRs that have been 18594 fixed are not listed here). As you can see, the number of bug fixes is 18595 quite large, so it is strongly recommended that users of earlier GCC 18596 3.x releases upgrade to GCC 3.2.1. 18597 18598 Internal Compiler Errors (multi-platform) 18599 18600 * [129]2521: (c++) ICE in build_ptrmemfunc, in cp/typeck.c 18601 * [130]5661: (c++) ICE instantiating template on array of unknown 18602 size (bad code) 18603 * [131]6419: (c++) ICE in make_decl_rtl for "longest" attribute on 18604 64-bit platforms 18605 * [132]6994: (c++) ICE in find_function_data 18606 * [133]7150: preprocessor: GCC -dM -E gives an ICE 18607 * [134]7160: ICE when optimizing branches without a return value 18608 * [135]7228: (c++) ICE when using member template and template 18609 function 18610 * [136]7266: (c++) ICE with -pedantic on missing typename 18611 * [137]7353: ICE from use of "Naming Types" extension, see above 18612 * [138]7411: ICE in instantiate_virtual_regs_1, in function.c 18613 * [139]7478: (c++) ICE on static_cast inside template 18614 * [140]7526: preprocessor core dump when _Pragma implies #pragma 18615 dependency 18616 * [141]7721: (c++) ICE on simple (but incorrect) template ([142]7803 18617 is a duplicate) 18618 * [143]7754: (c++) ICE on union with template parameter 18619 * [144]7788: (c++) redeclaring a definition as an incomplete class 18620 causes ICE 18621 * [145]8031: (c++) ICE in comptypes, in cp/typeck.c 18622 * [146]8055: preprocessor dies with SIG11 when building FreeBSD 18623 kernel 18624 * [147]8067: (c++) ICE due to mishandling of __FUNCTION__ and related 18625 variables 18626 * [148]8134: (c++) ICE in force_store_init_value on legal code 18627 * [149]8149: (c++) ICE on incomplete type 18628 * [150]8160: (c++) ICE in build_modify_expr, in cp/typeck.c: array 18629 initialization 18630 18631 C++ (compiler and library) bugs 18632 18633 * [151]5607: No pointer adjustment in covariant return types 18634 * [152]6579: Infinite loop with statement expressions in member 18635 initialization 18636 * [153]6803: Default copy constructor bug in GCC 3.1 18637 * [154]7176: g++ confused by friend and static member with same name 18638 * [155]7188: Segfault with template class and recursive (incorrect) 18639 initializer list 18640 * [156]7306: Regression: GCC 3.x fails to compile code with virtual 18641 inheritance if a method has a variable number of arguments 18642 * [157]7461: ctype<char>::classic_table() returns offset array on 18643 Cygwin 18644 * [158]7524: f(const float arg[3]) fails 18645 * [159]7584: Erroneous ambiguous base error on using declaration 18646 * [160]7676: Member template overloading problem 18647 * [161]7679: infinite loop when a right parenthesis is missing 18648 * [162]7811: default locale not taken from environment 18649 * [163]7961: compare( char *) implemented incorrectly in 18650 basic_string<> 18651 * [164]8071: basic_ostream::operator<<(streambuf*) loops forever if 18652 streambuf::underflow() leaves gptr() NULL (dups: [165]8127, 18653 [166]6745) 18654 * [167]8096: deque::at() throws std::range_error instead of 18655 std::out_of_range 18656 * [168]8127: cout << cin.rdbuf() infinite loop 18657 * [169]8218: Excessively large memory consumed for classes with large 18658 array members 18659 * [170]8287: GCC 3.2: Destructor called for non-constructed local 18660 object 18661 * [171]8347: empty vector range used in string construction causes 18662 core dump 18663 * [172]8348: fail() flag is set in istringstream when eof() flag is 18664 set 18665 * [173]8391: regression: infinite loop in cp/decl2.c(finish_file) 18666 18667 C and optimizer bugs 18668 18669 * [174]6627: -fno-align-functions doesn't seem to disable function 18670 alignment 18671 * [175]6631: life_analysis misoptimizes code to initialize fields of 18672 a structure 18673 * [176]7102: unsigned char division results in floating exception 18674 * [177]7120: Run once loop should *always* be unrolled 18675 (pessimization) 18676 * [178]7209: Bug involving array referencing and ?: operator 18677 * [179]7515: invalid inlining of global function with -O3 18678 * [180]7814: incorrect scheduling for glibc-2.2.92 strcpy test 18679 * [181]8467: bug in sibling call optimization 18680 18681 Preprocessor bugs 18682 18683 * [182]4890: incorrect line markers from the traditional preprocessor 18684 * [183]7357: -M option omits system headers files (making it the same 18685 as -MM) 18686 * [184]7358: Changes to Sun's make Dependencies 18687 * [185]7602: C++ header files found in CPLUS_INCLUDE_PATH treated as 18688 C headers 18689 * [186]7862: Interrupting GCC -MD removes .d file but not .o 18690 * [187]8190: Failed compilation deletes -MD dependency file 18691 * [188]8524: _Pragma within macro is improperly expanded 18692 18693 x86 specific (Intel/AMD) 18694 18695 * [189]5351: (i686-only) function pass-by-value structure copy 18696 corrupts stack ([190]7591 is a duplicate) 18697 * [191]6845, [192]7034, [193]7124, [194]7174: ICE's with 18698 -march=pentium3/pentium2/athlon (these are all the same underlying 18699 bug, in MMX register use) 18700 * [195]7134, [196]7375, [197]7390: ICE with -march=athlon (maybe same 18701 as above?) 18702 * [198]6890: xmmintrin.h, _MM_TRANSPOSE4_PS is broken 18703 * [199]6981: wrong code in 64-bit manipulation on x86 18704 * [200]7242: GCC -mcpu=pentium[23] doesn't define __tune_pentiumpro__ 18705 macro 18706 * [201]7396: ix86: cmpgt_ss, cmpge_ss, cmpngt_ss, and cmpnge_ss SSE 18707 intrinsics are broken 18708 * [202]7630: GCC 3.2 breaks on Mozilla 1.0's JS sources with 18709 -march=pentium4 18710 * [203]7693: Typo in i386 mmintrin.h header 18711 * [204]7723: ICE - Pentium3 sse - GCC 3.2 18712 * [205]7951: ICE on -march=pentium4 -O2 -mfpmath=sse 18713 * [206]8146: (i686 only) gcc 3.2 miscompiles gcc 2.95.3 18714 18715 PowerPC specific 18716 18717 * [207]5967: GCC bug when profiling nested functions on powerpc 18718 * [208]6984: wrong code generated with -O2, -O3, -Os for do-while 18719 loop on PowerPC 18720 * [209]7114: PowerPC: ICE building strcoll.op from glibc-2.2.5 18721 * [210]7130: miscompiled code for GCC-3.1 on 18722 powerpc-unknown-linux-gnu with -funroll-all-loops 18723 * [211]7133: PowerPC ICE: unrecognizable insn 18724 * [212]7380: ICE in extract_insn, at recog.c:2148 18725 * [213]8252: ICE on Altivec code with optimization turned on 18726 * [214]8451: Altivec ICE in GCC 3.2 18727 18728 HP/PA specific 18729 18730 * [215]7250: __ashrdi3 returns wrong value on 32 bit hppa 18731 18732 SPARC specific 18733 18734 * [216]6668: when using --disable-multilib, libgcc_s.so is installed 18735 in the wrong place on sparc-solaris 18736 * [217]7151: ICE when compiling for UltraSPARC 18737 * [218]7335: SPARC: ICE in verify_wide_reg (flow.c:557) with long 18738 double and -O1 18739 * [219]7842: [REGRESSION] SPARC code gen bug 18740 18741 ARM specific 18742 18743 * [220]7856: [arm] invalid offset in constant pool reference 18744 * [221]7967: optimization produces wrong code (ARM) 18745 18746 Alpha specific 18747 18748 * [222]7374: __builtin_fabsl broken on alpha 18749 18750 IBM s390 specific 18751 18752 * [223]7370: ICE in fixup_var_refs_1 on s390x 18753 * [224]7409: loop optimization bug on s390x-linux-gnu 18754 * [225]8232: s390x: ICE when using bcmp with int length argument 18755 18756 SCO specific 18757 18758 * [226]7623: SCO OpenServer build fails with machmode.def: undefined 18759 symbol: BITS_PER_UNIT 18760 18761 m68k/Coldfire specific 18762 18763 * [227]8314: crtbegin, crtend need to be multilib'ed for this 18764 platform 18765 18766 Documentation 18767 18768 * [228]761: Document some undocumented options 18769 * [229]5610: Fix documentation about invoking SSE instructions 18770 (-mfpmath=sse) 18771 * [230]7484: List -Wmissing-declarations as C-only option 18772 * [231]7531: -mcmodel not documented for x86-64 18773 * [232]8120: Update documentation of bad use of ## 18774 __________________________________________________________________ 18775 18776 GCC 3.2 18777 18778 3.2 is a small bug fix release, but there is a change to the 18779 application binary interface (ABI), hence the change to the second part 18780 of the version number. 18781 18782 The main purpose of the 3.2 release is to correct a couple of problems 18783 in the C++ ABI, with the intention of providing a stable interface 18784 going forward. Accordingly, 3.2 is only a small change to 3.1.1. 18785 18786 Bug Fixes 18787 18788 C++ 18789 18790 * [233]7320: g++ 3.2 relocation problem 18791 * [234]7470: vtable: virtual function pointers not in declaration 18792 order 18793 18794 libstdc++ 18795 18796 * [235]6410: Trouble with non-ASCII monetary symbols and wchar_t 18797 * [236]6503, [237]6642, [238]7186: Problems with comparing or 18798 subtracting various types of const and non-const iterators 18799 * [239]7216: ambiguity with basic_iostream::traits_type 18800 * [240]7220: problem with basic_istream::ignore(0,delimiter) 18801 * [241]7222: locale::operator==() doesn't work on std::locale("") 18802 * [242]7286: placement operator delete issue 18803 * [243]7442: cxxabi.h does not match the C++ ABI 18804 * [244]7445: poor performance of std::locale::classic() in 18805 multi-threaded applications 18806 18807 x86-64 specific 18808 18809 * [245]7291: off-by-one in generated inline bzero code for x86-64 18810 18811 18812 For questions related to the use of GCC, please consult these web 18813 pages and the [246]GCC manuals. If that fails, the 18814 [247]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 18815 web pages and the development of GCC are welcome on our developer 18816 list at [248]gcc (a] gcc.gnu.org. All of [249]our lists have public 18817 archives. 18818 18819 Copyright (C) [250]Free Software Foundation, Inc. Verbatim copying and 18820 distribution of this entire article is permitted in any medium, 18821 provided this notice is preserved. 18822 18823 These pages are [251]maintained by the GCC team. Last modified 18824 2022-10-26. 18825 18826 References 18827 18828 1. http://gcc.gnu.org/gcc-3.2/changes.html#3.2.3 18829 2. http://gcc.gnu.org/gcc-3.1/changes.html 18830 3. http://gcc.gnu.org/gcc-3.2/c++-abi.html 18831 4. https://gcc.gnu.org/PR3782 18832 5. https://gcc.gnu.org/PR6440 18833 6. https://gcc.gnu.org/PR7050 18834 7. https://gcc.gnu.org/PR7741 18835 8. https://gcc.gnu.org/PR7982 18836 9. https://gcc.gnu.org/PR8068 18837 10. https://gcc.gnu.org/PR8178 18838 11. https://gcc.gnu.org/PR8396 18839 12. https://gcc.gnu.org/PR8674 18840 13. https://gcc.gnu.org/PR9768 18841 14. https://gcc.gnu.org/PR9798 18842 15. https://gcc.gnu.org/PR9799 18843 16. https://gcc.gnu.org/PR9928 18844 17. https://gcc.gnu.org/PR10114 18845 18. https://gcc.gnu.org/PR10352 18846 19. https://gcc.gnu.org/PR10336 18847 20. https://gcc.gnu.org/PR8224 18848 21. https://gcc.gnu.org/PR8613 18849 22. https://gcc.gnu.org/PR8828 18850 23. https://gcc.gnu.org/PR9226 18851 24. https://gcc.gnu.org/PR9853 18852 25. https://gcc.gnu.org/PR9797 18853 26. https://gcc.gnu.org/PR9967 18854 27. https://gcc.gnu.org/PR10116 18855 28. https://gcc.gnu.org/PR10171 18856 29. https://gcc.gnu.org/PR10175 18857 30. https://gcc.gnu.org/PR8316 18858 31. https://gcc.gnu.org/PR9169 18859 32. https://gcc.gnu.org/PR9420 18860 33. https://gcc.gnu.org/PR9459 18861 34. https://gcc.gnu.org/PR9507 18862 35. https://gcc.gnu.org/PR9538 18863 36. https://gcc.gnu.org/PR9602 18864 37. https://gcc.gnu.org/PR9993 18865 38. https://gcc.gnu.org/PR10167 18866 39. https://gcc.gnu.org/PR9652 18867 40. https://gcc.gnu.org/PR10144 18868 41. https://gcc.gnu.org/PR8746 18869 42. https://gcc.gnu.org/PR9888 18870 43. https://gcc.gnu.org/PR9638 18871 44. https://gcc.gnu.org/PR9954 18872 45. https://gcc.gnu.org/PR7784 18873 46. https://gcc.gnu.org/PR7796 18874 47. https://gcc.gnu.org/PR8281 18875 48. https://gcc.gnu.org/PR8366 18876 49. https://gcc.gnu.org/PR8726 18877 50. https://gcc.gnu.org/PR9414 18878 51. https://gcc.gnu.org/PR10067 18879 52. https://gcc.gnu.org/PR7248 18880 53. https://gcc.gnu.org/PR8343 18881 54. https://gcc.gnu.org/PR9732 18882 55. https://gcc.gnu.org/PR10073 18883 56. https://gcc.gnu.org/PR7702 18884 57. https://gcc.gnu.org/PR9671 18885 58. https://gcc.gnu.org/PR8694 18886 59. https://gcc.gnu.org/PR9953 18887 60. https://gcc.gnu.org/PR10271 18888 61. https://gcc.gnu.org/PR6362 18889 62. https://gcc.gnu.org/PR10377 18890 63. https://gcc.gnu.org/PR6955 18891 64. https://gcc.gnu.org/PR5919 18892 65. https://gcc.gnu.org/PR7129 18893 66. https://gcc.gnu.org/PR7507 18894 67. https://gcc.gnu.org/PR7622 18895 68. https://gcc.gnu.org/PR7681 18896 69. https://gcc.gnu.org/PR9528 18897 70. https://gcc.gnu.org/PR8031 18898 71. https://gcc.gnu.org/PR8275 18899 72. https://gcc.gnu.org/PR8332 18900 73. https://gcc.gnu.org/PR8372 18901 74. https://gcc.gnu.org/PR8439 18902 75. https://gcc.gnu.org/PR8442 18903 76. https://gcc.gnu.org/PR8518 18904 77. https://gcc.gnu.org/PR8615 18905 78. https://gcc.gnu.org/PR8663 18906 79. https://gcc.gnu.org/PR8799 18907 80. https://gcc.gnu.org/PR9328 18908 81. https://gcc.gnu.org/PR9465 18909 82. https://gcc.gnu.org/PR47 18910 83. https://gcc.gnu.org/PR6745 18911 84. https://gcc.gnu.org/PR8214 18912 85. https://gcc.gnu.org/PR8493 18913 86. https://gcc.gnu.org/PR8332 18914 87. https://gcc.gnu.org/PR8503 18915 88. https://gcc.gnu.org/PR8727 18916 89. https://gcc.gnu.org/PR7445 18917 90. https://gcc.gnu.org/PR8230 18918 91. https://gcc.gnu.org/PR8399 18919 92. https://gcc.gnu.org/PR8662 18920 93. https://gcc.gnu.org/PR8707 18921 94. https://gcc.gnu.org/PR8708 18922 95. https://gcc.gnu.org/PR8790 18923 96. https://gcc.gnu.org/PR8887 18924 97. https://gcc.gnu.org/PR9076 18925 98. https://gcc.gnu.org/PR9151 18926 99. https://gcc.gnu.org/PR9168 18927 100. https://gcc.gnu.org/PR9269 18928 101. https://gcc.gnu.org/PR9322 18929 102. https://gcc.gnu.org/PR9433 18930 103. https://gcc.gnu.org/PR8032 18931 104. https://gcc.gnu.org/PR8639 18932 105. https://gcc.gnu.org/PR8794 18933 106. https://gcc.gnu.org/PR8832 18934 107. https://gcc.gnu.org/PR8988 18935 108. https://gcc.gnu.org/PR9492 18936 109. https://gcc.gnu.org/PR9267 18937 110. https://gcc.gnu.org/PR8344 18938 111. https://gcc.gnu.org/PR8524 18939 112. https://gcc.gnu.org/PR8880 18940 113. https://gcc.gnu.org/PR9090 18941 114. https://gcc.gnu.org/PR8588 18942 115. https://gcc.gnu.org/PR8599 18943 116. https://gcc.gnu.org/PR9506 18944 117. https://gcc.gnu.org/PR9484 18945 118. https://gcc.gnu.org/PR9292 18946 119. https://gcc.gnu.org/PR9293 18947 120. https://gcc.gnu.org/PR9295 18948 121. https://gcc.gnu.org/PR9296 18949 122. https://gcc.gnu.org/PR9316 18950 123. https://gcc.gnu.org/PR9493 18951 124. https://gcc.gnu.org/PR7341 18952 125. https://gcc.gnu.org/PR8947 18953 126. https://gcc.gnu.org/PR7448 18954 127. https://gcc.gnu.org/PR8882 18955 128. https://gcc.gnu.org/PR7445 18956 129. https://gcc.gnu.org/PR2521 18957 130. https://gcc.gnu.org/PR5661 18958 131. https://gcc.gnu.org/PR6419 18959 132. https://gcc.gnu.org/PR6994 18960 133. https://gcc.gnu.org/PR7150 18961 134. https://gcc.gnu.org/PR7160 18962 135. https://gcc.gnu.org/PR7228 18963 136. https://gcc.gnu.org/PR7266 18964 137. https://gcc.gnu.org/PR7353 18965 138. https://gcc.gnu.org/PR7411 18966 139. https://gcc.gnu.org/PR7478 18967 140. https://gcc.gnu.org/PR7526 18968 141. https://gcc.gnu.org/PR7721 18969 142. https://gcc.gnu.org/PR7803 18970 143. https://gcc.gnu.org/PR7754 18971 144. https://gcc.gnu.org/PR7788 18972 145. https://gcc.gnu.org/PR8031 18973 146. https://gcc.gnu.org/PR8055 18974 147. https://gcc.gnu.org/PR8067 18975 148. https://gcc.gnu.org/PR8134 18976 149. https://gcc.gnu.org/PR8149 18977 150. https://gcc.gnu.org/PR8160 18978 151. https://gcc.gnu.org/PR5607 18979 152. https://gcc.gnu.org/PR6579 18980 153. https://gcc.gnu.org/PR6803 18981 154. https://gcc.gnu.org/PR7176 18982 155. https://gcc.gnu.org/PR7188 18983 156. https://gcc.gnu.org/PR7306 18984 157. https://gcc.gnu.org/PR7461 18985 158. https://gcc.gnu.org/PR7524 18986 159. https://gcc.gnu.org/PR7584 18987 160. https://gcc.gnu.org/PR7676 18988 161. https://gcc.gnu.org/PR7679 18989 162. https://gcc.gnu.org/PR7811 18990 163. https://gcc.gnu.org/PR7961 18991 164. https://gcc.gnu.org/PR8071 18992 165. https://gcc.gnu.org/PR8127 18993 166. https://gcc.gnu.org/PR6745 18994 167. https://gcc.gnu.org/PR8096 18995 168. https://gcc.gnu.org/PR8127 18996 169. https://gcc.gnu.org/PR8218 18997 170. https://gcc.gnu.org/PR8287 18998 171. https://gcc.gnu.org/PR8347 18999 172. https://gcc.gnu.org/PR8348 19000 173. https://gcc.gnu.org/PR8391 19001 174. https://gcc.gnu.org/PR6627 19002 175. https://gcc.gnu.org/PR6631 19003 176. https://gcc.gnu.org/PR7102 19004 177. https://gcc.gnu.org/PR7120 19005 178. https://gcc.gnu.org/PR7209 19006 179. https://gcc.gnu.org/PR7515 19007 180. https://gcc.gnu.org/PR7814 19008 181. https://gcc.gnu.org/PR8467 19009 182. https://gcc.gnu.org/PR4890 19010 183. https://gcc.gnu.org/PR7357 19011 184. https://gcc.gnu.org/PR7358 19012 185. https://gcc.gnu.org/PR7602 19013 186. https://gcc.gnu.org/PR7862 19014 187. https://gcc.gnu.org/PR8190 19015 188. https://gcc.gnu.org/PR8524 19016 189. https://gcc.gnu.org/PR5351 19017 190. https://gcc.gnu.org/PR7591 19018 191. https://gcc.gnu.org/PR6845 19019 192. https://gcc.gnu.org/PR7034 19020 193. https://gcc.gnu.org/PR7124 19021 194. https://gcc.gnu.org/PR7174 19022 195. https://gcc.gnu.org/PR7134 19023 196. https://gcc.gnu.org/PR7375 19024 197. https://gcc.gnu.org/PR7390 19025 198. https://gcc.gnu.org/PR6890 19026 199. https://gcc.gnu.org/PR6981 19027 200. https://gcc.gnu.org/PR7242 19028 201. https://gcc.gnu.org/PR7396 19029 202. https://gcc.gnu.org/PR7630 19030 203. https://gcc.gnu.org/PR7693 19031 204. https://gcc.gnu.org/PR7723 19032 205. https://gcc.gnu.org/PR7951 19033 206. https://gcc.gnu.org/PR8146 19034 207. https://gcc.gnu.org/PR5967 19035 208. https://gcc.gnu.org/PR6984 19036 209. https://gcc.gnu.org/PR7114 19037 210. https://gcc.gnu.org/PR7130 19038 211. https://gcc.gnu.org/PR7133 19039 212. https://gcc.gnu.org/PR7380 19040 213. https://gcc.gnu.org/PR8252 19041 214. https://gcc.gnu.org/PR8451 19042 215. https://gcc.gnu.org/PR7250 19043 216. https://gcc.gnu.org/PR6668 19044 217. https://gcc.gnu.org/PR7151 19045 218. https://gcc.gnu.org/PR7335 19046 219. https://gcc.gnu.org/PR7842 19047 220. https://gcc.gnu.org/PR7856 19048 221. https://gcc.gnu.org/PR7967 19049 222. https://gcc.gnu.org/PR7374 19050 223. https://gcc.gnu.org/PR7370 19051 224. https://gcc.gnu.org/PR7409 19052 225. https://gcc.gnu.org/PR8232 19053 226. https://gcc.gnu.org/PR7623 19054 227. https://gcc.gnu.org/PR8314 19055 228. https://gcc.gnu.org/PR761 19056 229. https://gcc.gnu.org/PR5610 19057 230. https://gcc.gnu.org/PR7484 19058 231. https://gcc.gnu.org/PR7531 19059 232. https://gcc.gnu.org/PR8120 19060 233. https://gcc.gnu.org/PR7320 19061 234. https://gcc.gnu.org/PR7470 19062 235. https://gcc.gnu.org/PR6410 19063 236. https://gcc.gnu.org/PR6503 19064 237. https://gcc.gnu.org/PR6642 19065 238. https://gcc.gnu.org/PR7186 19066 239. https://gcc.gnu.org/PR7216 19067 240. https://gcc.gnu.org/PR7220 19068 241. https://gcc.gnu.org/PR7222 19069 242. https://gcc.gnu.org/PR7286 19070 243. https://gcc.gnu.org/PR7442 19071 244. https://gcc.gnu.org/PR7445 19072 245. https://gcc.gnu.org/PR7291 19073 246. https://gcc.gnu.org/onlinedocs/ 19074 247. mailto:gcc-help (a] gcc.gnu.org 19075 248. mailto:gcc (a] gcc.gnu.org 19076 249. https://gcc.gnu.org/lists.html 19077 250. https://www.fsf.org/ 19078 251. https://gcc.gnu.org/about.html 19079 ====================================================================== 19080 http://gcc.gnu.org/gcc-3.1/index.html 19081 19082 GCC 3.1 19083 19084 (This release series is no longer supported.) 19085 19086 July 27, 2002 19087 19088 The [1]GNU project and the GCC developers are pleased to announce the 19089 release of GCC 3.1.1. 19090 19091 The links below still apply to GCC 3.1.1. 19092 19093 May 15, 2002 19094 19095 The [2]GNU project and the GCC developers are pleased to announce the 19096 release of GCC 3.1. 19097 19098 GCC used to stand for the GNU C Compiler, but since the compiler 19099 supports several other languages aside from C, it now stands for the 19100 GNU Compiler Collection. 19101 19102 A list of [3]successful builds is updated as new information becomes 19103 available. 19104 19105 The GCC developers would like to thank the numerous people that have 19106 contributed [4]new features, improvements, bug fixes, and other changes 19107 as well as test results to GCC. This [5]amazing group of volunteers is 19108 what makes GCC successful. 19109 19110 For additional information about GCC please refer to the [6]GCC project 19111 web site or contact the [7]GCC development mailing list. 19112 19113 To obtain GCC please use [8]our mirror sites, or our CVS server. 19114 __________________________________________________________________ 19115 19116 19117 For questions related to the use of GCC, please consult these web 19118 pages and the [9]GCC manuals. If that fails, the 19119 [10]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 19120 web pages and the development of GCC are welcome on our developer 19121 list at [11]gcc (a] gcc.gnu.org. All of [12]our lists have public 19122 archives. 19123 19124 Copyright (C) [13]Free Software Foundation, Inc. Verbatim copying and 19125 distribution of this entire article is permitted in any medium, 19126 provided this notice is preserved. 19127 19128 These pages are [14]maintained by the GCC team. Last modified 19129 2022-10-26. 19130 19131 References 19132 19133 1. http://www.gnu.org/ 19134 2. http://www.gnu.org/ 19135 3. http://gcc.gnu.org/gcc-3.1/buildstat.html 19136 4. http://gcc.gnu.org/gcc-3.1/changes.html 19137 5. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 19138 6. http://gcc.gnu.org/index.html 19139 7. mailto:gcc (a] gcc.gnu.org 19140 8. http://gcc.gnu.org/mirrors.html 19141 9. https://gcc.gnu.org/onlinedocs/ 19142 10. mailto:gcc-help (a] gcc.gnu.org 19143 11. mailto:gcc (a] gcc.gnu.org 19144 12. https://gcc.gnu.org/lists.html 19145 13. https://www.fsf.org/ 19146 14. https://gcc.gnu.org/about.html 19147 ====================================================================== 19148 http://gcc.gnu.org/gcc-3.1/changes.html 19149 19150 GCC 3.1 Release Series 19151 Changes, New Features, and Fixes 19152 19153 Additional changes in GCC 3.1.1 19154 19155 * A bug related to how structures and unions are returned has been 19156 fixed for powerpc-*-netbsd*. 19157 * An important bug in the implementation of -fprefetch-loop-arrays 19158 has been fixed. Previously the optimization prefetched random 19159 blocks of memory for most targets except for i386. 19160 * The Java compiler now compiles Java programs much faster and also 19161 works with parallel make. 19162 * Nested functions have been fixed for mips*-*-netbsd*. 19163 * Some missing floating point support routines have beed added for 19164 mips*-*-netbsd*. 19165 * This [1]message gives additional information about the bugs fixed 19166 in this release. 19167 19168 Caveats 19169 19170 * The -traditional C compiler option has been deprecated and will be 19171 removed in GCC 3.3. (It remains possible to preprocess non-C code 19172 with the traditional preprocessor.) 19173 * The default debugging format for most ELF platforms (including 19174 GNU/Linux and FreeBSD; notable exception is Solaris) has changed 19175 from stabs to DWARF2. This requires GDB 5.1.1 or later. 19176 19177 General Optimizer Improvements 19178 19179 * Jan Hubicka, SuSE Labs, together with Richard Henderson, Red Hat, 19180 and Andreas Jaeger, SuSE Labs, has contributed [2]infrastructure 19181 for profile driven optimizations. 19182 Options -fprofile-arcs and -fbranch-probabilities can now be used 19183 to improve speed of the generated code by profiling the actual 19184 program behaviour on typical runs. In the absence of profile info 19185 the compiler attempts to guess the profile statically. 19186 * [3]SPEC2000 and SPEC95 benchmark suites are now used daily to 19187 monitor performance of the generated code. 19188 According to the SPECInt2000 results on an AMD Athlon CPU, the code 19189 generated by GCC 3.1 is 6% faster on the average (8.2% faster with 19190 profile feedback) compared to GCC 3.0. The code produced by GCC 3.0 19191 is about 2.1% faster compared to 2.95.3. Tests were done using the 19192 -O2 -march=athlon command-line options. 19193 * Alexandre Oliva, of Red Hat, has generalized the tree inlining 19194 infrastructure developed by CodeSourcery, LLC for the C++ front 19195 end, so that it is now used in the C front end too. Inlining 19196 functions as trees exposes them earlier to the compiler, giving it 19197 more opportunities for optimization. 19198 * Support for data prefetching instructions has been added to the GCC 19199 back end and several targets. A new __builtin_prefetch intrinsic is 19200 available to explicitly insert prefetch instructions and 19201 experimental support for loop array prefetching has been added (see 19202 -fprefetch-loop-array documentation). 19203 * Support for emitting debugging information for macros has been 19204 added for DWARF2. It is activated using -g3. 19205 19206 New Languages and Language specific improvements 19207 19208 C/C++ 19209 19210 * A few more [4]ISO C99 features. 19211 * The preprocessor is 10-50% faster than the preprocessor in GCC 3.0. 19212 * The preprocessor's symbol table has been merged with the symbol 19213 table of the C, C++ and Objective-C front ends. 19214 * The preprocessor consumes less memory than the preprocessor in GCC 19215 3.0, often significantly so. On normal input files, it typically 19216 consumes less memory than pre-3.0 cccp-based GCC, too. 19217 19218 C++ 19219 19220 * -fhonor-std and -fno-honor-std have been removed. -fno-honor-std 19221 was a workaround to allow std compliant code to work with the 19222 non-std compliant libstdc++-v2. libstdc++-v3 is std compliant. 19223 * The C++ ABI has been fixed so that void (A::*)() const is mangled 19224 as "M1AKFvvE", rather than "MK1AFvvE" as before. This change only 19225 affects pointer to cv-qualified member function types. 19226 * The C++ ABI has been changed to correctly handle this code: 19227 struct A { 19228 void operator delete[] (void *, size_t); 19229 }; 19230 19231 struct B : public A { 19232 }; 19233 19234 new B[10]; 19235 19236 The amount of storage allocated for the array will be greater than 19237 it was in 3.0, in order to store the number of elements in the 19238 array, so that the correct size can be passed to operator delete[] 19239 when the array is deleted. Previously, the value passed to operator 19240 delete[] was unpredictable. 19241 This change will only affect code that declares a two-argument 19242 operator delete[] with a second parameter of type size_t in a base 19243 class, and does not override that definition in a derived class. 19244 * The C++ ABI has been changed so that: 19245 struct A { 19246 void operator delete[] (void *, size_t); 19247 void operator delete[] (void *); 19248 }; 19249 19250 does not cause unnecessary storage to be allocated when an array of 19251 A objects is allocated. 19252 This change will only affect code that declares both of these forms 19253 of operator delete[], and declared the two-argument form before the 19254 one-argument form. 19255 * The C++ ABI has been changed so that when a parameter is passed by 19256 value, any cleanup for that parameter is performed in the caller, 19257 as specified by the ia64 C++ ABI, rather than the called function 19258 as before. As a result, classes with a non-trivial destructor but a 19259 trivial copy constructor will be passed and returned by invisible 19260 reference, rather than by bitwise copy as before. 19261 * G++ now supports the "named return value optimization": for code 19262 like 19263 A f () { 19264 A a; 19265 ... 19266 return a; 19267 } 19268 19269 G++ will allocate a in the return value slot, so that the return 19270 becomes a no-op. For this to work, all return statements in the 19271 function must return the same variable. 19272 * Improvements to the C++ library are listed in [5]the libstdc++-v3 19273 FAQ. 19274 19275 Objective-C 19276 19277 * Annoying linker warnings (due to incorrect code being generated) 19278 have been fixed. 19279 * If a class method cannot be found, the compiler no longer issues a 19280 warning if a corresponding instance method exists in the root 19281 class. 19282 * Forward @protocol declarations have been fixed. 19283 * Loading of categories has been fixed in certain situations (GNU run 19284 time only). 19285 * The class lookup in the run-time library has been rewritten so that 19286 class method dispatch is more than twice as fast as it used to be 19287 (GNU run time only). 19288 19289 Java 19290 19291 * libgcj now includes RMI, java.lang.ref.*, javax.naming, and 19292 javax.transaction. 19293 * Property files and other system resources can be compiled into 19294 executables which use libgcj using the new gcj --resource feature. 19295 * libgcj has been ported to more platforms. In particular there is 19296 now a mostly-functional mingw32 (Windows) target port. 19297 * JNI and CNI invocation interfaces were implemented, so gcj-compiled 19298 Java code can now be called from a C/C++ application. 19299 * gcj can now use builtin functions for certain known methods, for 19300 instance Math.cos. 19301 * gcj can now automatically remove redundant array-store checks in 19302 some common cases. 19303 * The --no-store-checks optimization option was added. This can be 19304 used to omit runtime store checks for code which is known not to 19305 throw ArrayStoreException 19306 * The following third party interface standards were added to libgcj: 19307 org.w3c.dom and org.xml.sax. 19308 * java.security has been merged with GNU Classpath. The new package 19309 is now JDK 1.2 compliant, and much more complete. 19310 * A bytecode verifier was added to the libgcj interpreter. 19311 * java.lang.Character was rewritten to comply with the Unicode 3.0 19312 standard, and improve performance. 19313 * Partial support for many more locales was added to libgcj. 19314 * Socket timeouts have been implemented. 19315 * libgcj has been merged into a single shared library. There are no 19316 longer separate shared libraries for the garbage collector and 19317 zlib. 19318 * Several performance improvements were made to gcj and libgcj: 19319 + Hash synchronization (thin locks) 19320 + A special allocation path for finalizer-free objects 19321 + Thread-local allocation 19322 + Parallel GC, and other GC tweaks 19323 19324 Fortran 19325 19326 Fortran improvements are listed in [6]the Fortran documentation. 19327 19328 Ada 19329 19330 [7]AdaCore, has contributed its GNAT Ada 95 front end and associated 19331 tools. The GNAT compiler fully implements the Ada language as defined 19332 by the ISO/IEC 8652 standard. 19333 19334 Please note that the integration of the Ada front end is still work in 19335 progress. 19336 19337 New Targets and Target Specific Improvements 19338 19339 * Hans-Peter Nilsson has contributed a port to MMIX, the CPU 19340 architecture used in new editions of Donald E. Knuth's The Art of 19341 Computer Programming. 19342 * Axis Communications has contributed its port to the CRIS CPU 19343 architecture, used in the ETRAX system-on-a-chip series. 19344 * Alexandre Oliva, of Red Hat, has contributed a port to the SuperH 19345 SH5 64-bit RISC microprocessor architecture, extending the existing 19346 SH port. 19347 * UltraSPARC is fully supported in 64-bit mode. The option -m64 19348 enables it. 19349 * For compatibility with the Sun compiler #pragma redefine_extname 19350 has been implemented on Solaris. 19351 * The x86 back end has had some noticeable work done to it. 19352 + SuSE Labs developers Jan Hubicka, Bo Thorsen and Andreas 19353 Jaeger have contributed a port to the AMD x86-64 architecture. 19354 For more information on x86-64 see http://www.x86-64.org. 19355 + The compiler now supports MMX, 3DNow!, SSE, and SSE2 19356 instructions. Options -mmmx, -m3dnow, -msse, and -msse2 will 19357 enable the respective instruction sets. Intel C++ compatible 19358 MMX/3DNow!/SSE intrinsics are implemented. SSE2 intrinsics 19359 will be added in next major release. 19360 + Following those improvements, targets for Pentium MMX, K6-2, 19361 K6-3, Pentium III, Pentium 4, and Athlon 4 Mobile/XP/MP were 19362 added. Refer to the documentation on -march= and -mcpu= 19363 options for details. 19364 + For those targets that support it, -mfpmath=sse will cause the 19365 compiler to generate SSE/SSE2 instructions for floating point 19366 math instead of x87 instructions. Usually, this will lead to 19367 quicker code -- especially on the Pentium 4. Note that only 19368 scalar floating point instructions are used and GCC does not 19369 exploit SIMD features yet. 19370 + Prefetch support has been added to the Pentium III, Pentium 4, 19371 K6-2, K6-3, and Athlon series. 19372 + Code generated for floating point to integer conversions has 19373 been improved leading to better performance of many 3D 19374 applications. 19375 * The PowerPC back end has added 64-bit PowerPC GNU/Linux support. 19376 * C++ support for AIX has been improved. 19377 * Aldy Hernandez, of Red Hat, Inc, has contributed extensions to the 19378 PowerPC port supporting the AltiVec programming model (SIMD). The 19379 support, though presently useful, is experimental and is expected 19380 to stabilize for 3.2. The support is written to conform to 19381 Motorola's AltiVec specs. See -maltivec. 19382 19383 Obsolete Systems 19384 19385 Support for a number of older systems has been declared obsolete in GCC 19386 3.1. Unless there is activity to revive them, the next release of GCC 19387 will have their sources permanently removed. 19388 19389 All configurations of the following processor architectures have been 19390 declared obsolete: 19391 * MIL-STD-1750A, 1750a-*-* 19392 * AMD A29k, a29k-*-* 19393 * Convex, c*-convex-* 19394 * Clipper, clipper-*-* 19395 * Elxsi, elxsi-*-* 19396 * Intel i860, i860-*-* 19397 * Sun picoJava, pj-*-* and pjl-*-* 19398 * Western Electric 32000, we32k-*-* 19399 19400 Most configurations of the following processor architectures have been 19401 declared obsolete, but we are preserving a few systems which may have 19402 active developers. It is unlikely that the remaining systems will 19403 survive much longer unless we see definite signs of port activity. 19404 * Motorola 88000 except 19405 + Generic a.out, m88k-*-aout* 19406 + Generic SVR4, m88k-*-sysv4 19407 + OpenBSD, m88k-*-openbsd* 19408 * NS32k except 19409 + NetBSD, ns32k-*-netbsd* 19410 + OpenBSD, ns32k-*-openbsd*. 19411 * ROMP except 19412 + OpenBSD, romp-*-openbsd*. 19413 19414 Finally, only some configurations of these processor architectures are 19415 being obsoleted. 19416 * Alpha: 19417 + OSF/1, alpha*-*-osf[123]*. (Digital Unix and Tru64 Unix, aka 19418 alpha*-*-osf[45], are still supported.) 19419 * ARM: 19420 + RISCiX, arm-*-riscix*. 19421 * i386: 19422 + 386BSD, i?86-*-bsd* 19423 + Chorus, i?86-*-chorusos* 19424 + DG/UX, i?86-*-dgux* 19425 + FreeBSD 1.x, i?86-*-freebsd1.* 19426 + IBM AIX, i?86-*-aix* 19427 + ISC UNIX, i?86-*-isc* 19428 + GNU/Linux with pre-BFD linker, i?86-*-linux*oldld* 19429 + NEXTstep, i?86-next-* 19430 + OSF UNIX, i?86-*-osf1* and i?86-*-osfrose* 19431 + RTEMS/coff, i?86-*-rtemscoff* 19432 + RTEMS/go32, i?86-go32-rtems* 19433 + Sequent/BSD, i?86-sequent-bsd* 19434 + Sequent/ptx before version 3, i?86-sequent-ptx[12]* and 19435 i?86-sequent-sysv3* 19436 + SunOS, i?86-*-sunos* 19437 * Motorola 68000: 19438 + Altos, m68[k0]*-altos-* 19439 + Apollo, m68[k0]*-apollo-* 19440 + Apple A/UX, m68[k0]*-apple-* 19441 + Bull, m68[k0]*-bull-* 19442 + Convergent, m68[k0]*-convergent-* 19443 + Generic SVR3, m68[k0]*-*-sysv3* 19444 + ISI, m68[k0]*-isi-* 19445 + LynxOS, m68[k0]*-*-lynxos* 19446 + NEXT, m68[k0]*-next-* 19447 + RTEMS/coff, m68[k0]*-*-rtemscoff* 19448 + Sony, m68[k0]*-sony-* 19449 * MIPS: 19450 + DEC Ultrix, mips-*-ultrix* and mips-dec-* 19451 + Generic BSD, mips-*-bsd* 19452 + Generic System V, mips-*-sysv* 19453 + IRIX before version 5, mips-sgi-irix[1234]* 19454 + RiscOS, mips-*-riscos* 19455 + Sony, mips-sony-* 19456 + Tandem, mips-tandem-* 19457 * SPARC: 19458 + RTEMS/a.out, sparc-*-rtemsaout*. 19459 19460 Documentation improvements 19461 19462 * The old manual ("Using and Porting the GNU Compiler Collection") 19463 has been replaced by a users manual ("Using the GNU Compiler 19464 Collection") and a separate internals reference manual ("GNU 19465 Compiler Collection Internals"). 19466 * More complete and much improved documentation about GCC's internal 19467 representation used by the C and C++ front ends. 19468 * Many cleanups and improvements in general. 19469 19470 19471 For questions related to the use of GCC, please consult these web 19472 pages and the [8]GCC manuals. If that fails, the 19473 [9]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 19474 web pages and the development of GCC are welcome on our developer 19475 list at [10]gcc (a] gcc.gnu.org. All of [11]our lists have public 19476 archives. 19477 19478 Copyright (C) [12]Free Software Foundation, Inc. Verbatim copying and 19479 distribution of this entire article is permitted in any medium, 19480 provided this notice is preserved. 19481 19482 These pages are [13]maintained by the GCC team. Last modified 19483 2022-10-26. 19484 19485 References 19486 19487 1. https://gcc.gnu.org/ml/gcc/2002-07/msg01208.html 19488 2. http://gcc.gnu.org/news/profiledriven.html 19489 3. http://gcc.gnu.org/benchmarks/ 19490 4. http://gcc.gnu.org/c99status.html 19491 5. https://gcc.gnu.org/onlinedocs/libstdc++/faq.html 19492 6. https://gcc.gnu.org/onlinedocs/gcc-3.1.1/g77/News.html 19493 7. https://www.adacore.com/ 19494 8. https://gcc.gnu.org/onlinedocs/ 19495 9. mailto:gcc-help (a] gcc.gnu.org 19496 10. mailto:gcc (a] gcc.gnu.org 19497 11. https://gcc.gnu.org/lists.html 19498 12. https://www.fsf.org/ 19499 13. https://gcc.gnu.org/about.html 19500 ====================================================================== 19501 http://gcc.gnu.org/gcc-3.0/index.html 19502 19503 GCC 3.0.4 19504 19505 (This release series is no longer supported.) 19506 19507 February 20, 2002 19508 19509 The [1]GNU project and the GCC developers are pleased to announce the 19510 release of GCC 3.0.4, which is a bug-fix release for the GCC 3.0 19511 series. 19512 19513 GCC used to stand for the GNU C Compiler, but since the compiler 19514 supports several other languages aside from C, it now stands for the 19515 GNU Compiler Collection. 19516 19517 GCC 3.0.x has several new optimizations, new targets, new languages and 19518 many other new features, relative to GCC 2.95.x. See the [2]new 19519 features page for a more complete list. 19520 19521 A list of [3]successful builds is updated as new information becomes 19522 available. 19523 19524 The GCC developers would like to thank the numerous people that have 19525 contributed new features, test results, bug fixes, etc to GCC. This 19526 [4]amazing group of volunteers is what makes GCC successful. 19527 19528 And finally, we can't in good conscience fail to mention some 19529 [5]caveats to using GCC 3.0.x. 19530 19531 For additional information about GCC please refer to the [6]GCC project 19532 web site or contact the [7]GCC development mailing list. 19533 19534 To obtain GCC please use [8]our mirror sites, or our CVS server. 19535 __________________________________________________________________ 19536 19537 Previous 3.0.x Releases 19538 19539 December 20, 2001: GCC 3.0.3 has been released. 19540 October 25, 2001: GCC 3.0.2 has been released. 19541 August 20, 2001: GCC 3.0.1 has been released. 19542 June 18, 2001: GCC 3.0 has been released. 19543 19544 19545 For questions related to the use of GCC, please consult these web 19546 pages and the [9]GCC manuals. If that fails, the 19547 [10]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 19548 web pages and the development of GCC are welcome on our developer 19549 list at [11]gcc (a] gcc.gnu.org. All of [12]our lists have public 19550 archives. 19551 19552 Copyright (C) [13]Free Software Foundation, Inc. Verbatim copying and 19553 distribution of this entire article is permitted in any medium, 19554 provided this notice is preserved. 19555 19556 These pages are [14]maintained by the GCC team. Last modified 19557 2022-10-26. 19558 19559 References 19560 19561 1. http://www.gnu.org/ 19562 2. http://gcc.gnu.org/gcc-3.0/features.html 19563 3. http://gcc.gnu.org/gcc-3.0/buildstat.html 19564 4. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 19565 5. http://gcc.gnu.org/gcc-3.0/caveats.html 19566 6. http://gcc.gnu.org/index.html 19567 7. mailto:gcc (a] gcc.gnu.org 19568 8. http://gcc.gnu.org/mirrors.html 19569 9. https://gcc.gnu.org/onlinedocs/ 19570 10. mailto:gcc-help (a] gcc.gnu.org 19571 11. mailto:gcc (a] gcc.gnu.org 19572 12. https://gcc.gnu.org/lists.html 19573 13. https://www.fsf.org/ 19574 14. https://gcc.gnu.org/about.html 19575 ====================================================================== 19576 http://gcc.gnu.org/gcc-3.0/features.html 19577 19578 GCC 3.0 New Features 19579 19580 Additional changes in GCC 3.0.4 19581 19582 * GCC 3.0 now supports newer versions of the [1]NetBSD operating 19583 system, which use the ELF object file format, on x86 processors. 19584 * Correct debugging information is generated from functions that have 19585 lines from multiple files (e.g. yacc output). 19586 * A fix for whitespace handling in the -traditional preprocessor, 19587 which can affect Fortran. 19588 * Fixes to the exception handling runtime. 19589 * More fixes for bad code generation in C++. 19590 * A fix for shared library generation under AIX 4.3. 19591 * Documentation updates. 19592 * Port of GCC to Tensilica's Xtensa processor contributed. 19593 * A fix for compiling the PPC Linux kernel (FAT fs wouldn't link). 19594 19595 Additional changes in GCC 3.0.3 19596 19597 * A fix to correct an accidental change to the PowerPC ABI. 19598 * Fixes for bad code generation on a variety of architectures. 19599 * Improvements to the debugging information generated for C++ 19600 classes. 19601 * Fixes for bad code generation in C++. 19602 * A fix to avoid crashes in the C++ demangler. 19603 * A fix to the C++ standard library to avoid buffer overflows. 19604 * Miscellaneous improvements for a variety of architectures. 19605 19606 Additional changes in GCC 3.0.2 19607 19608 * Fixes for bad code generation during loop unrolling. 19609 * Fixes for bad code generation by the sibling call optimization. 19610 * Minor improvements to x86 code generation. 19611 * Implementation of function descriptors in C++ vtables for IA64. 19612 * Numerous minor bug-fixes. 19613 19614 Additional changes in GCC 3.0.1 19615 19616 * C++ fixes for incorrect code-generation. 19617 * Improved cross-compiling support for the C++ standard library. 19618 * Fixes for some embedded targets that worked in GCC 2.95.3, but not 19619 in GCC 3.0. 19620 * Fixes for various exception-handling bugs. 19621 * A port to the S/390 architecture. 19622 19623 General Optimizer Improvements 19624 19625 * [2]Basic block reordering pass. 19626 * New if-conversion pass with support for conditional (predicated) 19627 execution. 19628 * New tail call and sibling call elimination optimizations. 19629 * New register renaming pass. 19630 * New (experimental) [3]static single assignment (SSA) representation 19631 support. 19632 * New dead-code elimination pass implemented using the SSA 19633 representation. 19634 * [4]Global null pointer test elimination. 19635 * [5]Global code hoisting/unification. 19636 * More builtins and optimizations for stdio.h, string.h and old BSD 19637 functions, as well as for ISO C99 functions. 19638 * New builtin __builtin_expect for giving hints to the branch 19639 predictor. 19640 19641 New Languages and Language specific improvements 19642 19643 * The GNU Compiler for the Java(TM) language (GCJ) is now integrated 19644 and supported, including the run-time library containing most 19645 common non-GUI Java classes, a bytecode interpreter, and the Boehm 19646 conservative garbage collector. Many bugs have been fixed. GCJ can 19647 compile Java source or Java bytecodes to either native code or Java 19648 class files, and supports native methods written in either the 19649 standard JNI or the more efficient and convenient CNI. 19650 * Here is a [6]partial list of C++ improvements, both new features 19651 and those no longer supported. 19652 * New C++ ABI. On the IA-64 platform GCC is capable of 19653 inter-operating with other IA-64 compilers. 19654 * The new ABI also significantly reduces the size of symbol and debug 19655 information. 19656 * New C++ support library and many C++ bug fixes, vastly improving 19657 our conformance to the ISO C++ standard. 19658 * New [7]inliner for C++. 19659 * Rewritten C preprocessor, integrated into the C, C++ and Objective 19660 C compilers, with very many improvements including ISO C99 support 19661 and [8]improvements to dependency generation. 19662 * Support for more [9]ISO C99 features. 19663 * Many improvements to support for checking calls to format functions 19664 such as printf and scanf, including support for ISO C99 format 19665 features, extensions from the Single Unix Specification and GNU 19666 libc 2.2, checking of strfmon formats and features to assist in 19667 auditing for format string security bugs. 19668 * New warnings for C code that may have undefined semantics because 19669 of violations of sequence point rules in the C standard (such as a 19670 = a++;, a[n] = b[n++]; and a[i++] = i;), included in -Wall. 19671 * Additional warning option -Wfloat-equal. 19672 * Improvements to -Wtraditional. 19673 * Fortran improvements are listed in [10]the Fortran documentation. 19674 19675 New Targets and Target Specific Improvements 19676 19677 * New x86 back end, generating much improved code. 19678 * Support for a generic i386-elf target contributed. 19679 * New option to emit x86 assembly code using Intel style syntax 19680 (-mintel-syntax). 19681 * HPUX 11 support contributed. 19682 * Improved PowerPC code generation, including scheduled prologue and 19683 epilogue. 19684 * Port of GCC to Intel's IA-64 processor contributed. 19685 * Port of GCC to Motorola's MCore 210 and 340 contributed. 19686 * New unified back-end for Arm, Thumb and StrongArm contributed. 19687 * Port of GCC to Intel's XScale processor contributed. 19688 * Port of GCC to Atmel's AVR microcontrollers contributed. 19689 * Port of GCC to Mitsubishi's D30V processor contributed. 19690 * Port of GCC to Matsushita's AM33 processor (a member of the MN10300 19691 processor family) contributed. 19692 * Port of GCC to Fujitsu's FR30 processor contributed. 19693 * Port of GCC to Motorola's 68HC11 and 68HC12 processors contributed. 19694 * Port of GCC to Sun's picoJava processor core contributed. 19695 19696 Documentation improvements 19697 19698 * Substantially rewritten and improved C preprocessor manual. 19699 * Many improvements to other documentation. 19700 * Manpages for gcc, cpp and gcov are now generated automatically from 19701 the master Texinfo manual, eliminating the problem of manpages 19702 being out of date. (The generated manpages are only extracts from 19703 the full manual, which is provided in Texinfo form, from which 19704 info, HTML, other formats and a printed manual can be generated.) 19705 * Generated info files are included in the release tarballs alongside 19706 their Texinfo sources, avoiding problems on some platforms with 19707 building makeinfo as part of the GCC distribution. 19708 19709 Other significant improvements 19710 19711 * Garbage collection used internally by the compiler for most memory 19712 allocation instead of obstacks. 19713 * Lengauer and Tarjan algorithm used for computing dominators in the 19714 CFG. This algorithm can be significantly faster and more space 19715 efficient than our older algorithm. 19716 * gccbug script provided to assist in submitting bug reports to our 19717 bug tracking system. (Bug reports previously submitted directly to 19718 our mailing lists, for which you received no bug tracking number, 19719 should be submitted again using gccbug if you can reproduce the 19720 problem with GCC 3.0.) 19721 * The internal libgcc library is [11]built as a shared library on 19722 systems that support it. 19723 * Extensive testsuite included with GCC, with many new tests. In 19724 addition to tests for GCC bugs that have been fixed, many tests 19725 have been added for language features, compiler warnings and 19726 builtin functions. 19727 * Additional language-independent warning options -Wpacked, -Wpadded, 19728 -Wunreachable-code and -Wdisabled-optimization. 19729 * Target-independent options -falign-functions, -falign-loops and 19730 -falign-jumps. 19731 19732 Plus a great many bug fixes and almost all the [12]features found in 19733 GCC 2.95. 19734 19735 19736 For questions related to the use of GCC, please consult these web 19737 pages and the [13]GCC manuals. If that fails, the 19738 [14]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 19739 web pages and the development of GCC are welcome on our developer 19740 list at [15]gcc (a] gcc.gnu.org. All of [16]our lists have public 19741 archives. 19742 19743 Copyright (C) [17]Free Software Foundation, Inc. Verbatim copying and 19744 distribution of this entire article is permitted in any medium, 19745 provided this notice is preserved. 19746 19747 These pages are [18]maintained by the GCC team. Last modified 19748 2022-10-26. 19749 19750 References 19751 19752 1. http://www.netbsd.org/ 19753 2. http://gcc.gnu.org/news/reorder.html 19754 3. http://gcc.gnu.org/news/ssa.html 19755 4. http://gcc.gnu.org/news/null.html 19756 5. http://gcc.gnu.org/news/unify.html 19757 6. http://gcc.gnu.org/gcc-3.0/c++features.html 19758 7. http://gcc.gnu.org/news/inlining.html 19759 8. http://gcc.gnu.org/news/dependencies.html 19760 9. http://gcc.gnu.org/c99status.html 19761 10. https://gcc.gnu.org/onlinedocs/gcc-3.4.6/g77/News.html 19762 11. http://gcc.gnu.org/gcc-3.0/libgcc.html 19763 12. http://gcc.gnu.org/gcc-2.95/features.html 19764 13. https://gcc.gnu.org/onlinedocs/ 19765 14. mailto:gcc-help (a] gcc.gnu.org 19766 15. mailto:gcc (a] gcc.gnu.org 19767 16. https://gcc.gnu.org/lists.html 19768 17. https://www.fsf.org/ 19769 18. https://gcc.gnu.org/about.html 19770 ====================================================================== 19771 http://gcc.gnu.org/gcc-3.0/caveats.html 19772 19773 GCC 3.0 Caveats 19774 19775 * -fstrict-aliasing is now part of -O2 and higher optimization 19776 levels. This allows the compiler to assume the strictest aliasing 19777 rules applicable to the language being compiled. For C and C++, 19778 this activates optimizations based on the type of expressions. This 19779 optimization may thus break old, non-compliant code. 19780 * Enumerations are now properly promoted to int in function 19781 parameters and function returns. Normally this change is not 19782 visible, but when using -fshort-enums this is an ABI change. 19783 * The undocumented extension that allowed C programs to have a label 19784 at the end of a compound statement has been deprecated and may be 19785 removed in a future version. Programs that now generate a warning 19786 about this may be fixed by adding a null statement (a single 19787 semicolon) after the label. 19788 * The poorly documented extension that allowed string constants in C, 19789 C++ and Objective C to contain unescaped newlines has been 19790 deprecated and may be removed in a future version. Programs using 19791 this extension may be fixed in several ways: the bare newline may 19792 be replaced by \n, or preceded by \n\, or string concatenation may 19793 be used with the bare newline preceded by \n" and " placed at the 19794 start of the next line. 19795 * The Chill compiler is not included in GCC 3.0, because of the lack 19796 of a volunteer to convert it to use garbage collection. 19797 * Certain non-standard iostream methods from earlier versions of 19798 libstdc++ are not included in libstdc++ v3, i.e. filebuf::attach, 19799 ostream::form, and istream::gets. 19800 * The new C++ ABI is not yet fully supported by current (as of 19801 2001-07-01) releases and development versions of GDB, or any 19802 earlier versions. There is a problem setting breakpoints by line 19803 number, and other related issues that have been fixed in GCC 3.0 19804 but not yet handled in GDB: 19805 [1]https://gcc.gnu.org/ml/gcc-bugs/2001-06/msg00421.html 19806 19807 19808 For questions related to the use of GCC, please consult these web 19809 pages and the [2]GCC manuals. If that fails, the 19810 [3]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 19811 web pages and the development of GCC are welcome on our developer 19812 list at [4]gcc (a] gcc.gnu.org. All of [5]our lists have public archives. 19813 19814 Copyright (C) [6]Free Software Foundation, Inc. Verbatim copying and 19815 distribution of this entire article is permitted in any medium, 19816 provided this notice is preserved. 19817 19818 These pages are [7]maintained by the GCC team. Last modified 19819 2022-10-26. 19820 19821 References 19822 19823 1. https://gcc.gnu.org/ml/gcc-bugs/2001-06/msg00421.html 19824 2. https://gcc.gnu.org/onlinedocs/ 19825 3. mailto:gcc-help (a] gcc.gnu.org 19826 4. mailto:gcc (a] gcc.gnu.org 19827 5. https://gcc.gnu.org/lists.html 19828 6. https://www.fsf.org/ 19829 7. https://gcc.gnu.org/about.html 19830 ====================================================================== 19831 http://gcc.gnu.org/gcc-2.95/index.html 19832 19833 GCC 2.95 19834 19835 (This release series is no longer supported.) 19836 19837 March 16, 2001: The GNU project and the GCC developers are pleased to 19838 announce the release of GCC version 2.95.3. 19839 19840 Release History 19841 19842 GCC 2.95.3 19843 March 16, 2001 19844 19845 GCC 2.95.2 19846 October 27, 1999 19847 19848 GCC 2.95.1 19849 August 19, 1999 19850 19851 GCC 2.95 19852 July 31, 1999. This is the first release of GCC since the April 19853 1999 GCC/EGCS reunification and includes nearly a year's worth 19854 of new development and bugfixes. 19855 19856 References and Acknowledgements 19857 19858 GCC used to stand for the GNU C Compiler, but since the compiler 19859 supports several other languages aside from C, it now stands for the 19860 GNU Compiler Collection. 19861 19862 The whole suite has been extensively [1]regression tested and 19863 [2]package tested. It should be reliable and suitable for widespread 19864 use. 19865 19866 The compiler has several new optimizations, new targets, new languages 19867 and other new features. See the [3]new features page for a more 19868 complete list of new features found in the GCC 2.95 releases. 19869 19870 The sources include installation instructions in both HTML and 19871 plaintext forms in the install directory in the distribution. However, 19872 the most up to date installation instructions and [4]build/test status 19873 are on the web pages. We will update those pages as new information 19874 becomes available. 19875 19876 The GCC developers would like to thank the numerous people that have 19877 contributed new features, test results, bugfixes, etc to GCC. This 19878 [5]amazing group of volunteers is what makes GCC successful. 19879 19880 And finally, we can't in good conscience fail to mention some 19881 [6]caveats to using GCC 2.95. 19882 19883 Download GCC 2.95 from one of our many [7]mirror sites. 19884 19885 For additional information about GCC please see the [8]GCC project web 19886 server or contact the [9]GCC development mailing list. 19887 19888 19889 For questions related to the use of GCC, please consult these web 19890 pages and the [10]GCC manuals. If that fails, the 19891 [11]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 19892 web pages and the development of GCC are welcome on our developer 19893 list at [12]gcc (a] gcc.gnu.org. All of [13]our lists have public 19894 archives. 19895 19896 Copyright (C) [14]Free Software Foundation, Inc. Verbatim copying and 19897 distribution of this entire article is permitted in any medium, 19898 provided this notice is preserved. 19899 19900 These pages are [15]maintained by the GCC team. Last modified 19901 2022-10-26. 19902 19903 References 19904 19905 1. http://gcc.gnu.org/gcc-2.95/regress.html 19906 2. http://gcc.gnu.org/gcc-2.95/othertest.html 19907 3. http://gcc.gnu.org/gcc-2.95/features.html 19908 4. http://gcc.gnu.org/gcc-2.95/buildstat.html 19909 5. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 19910 6. http://gcc.gnu.org/gcc-2.95/caveats.html 19911 7. http://gcc.gnu.org/mirrors.html 19912 8. http://gcc.gnu.org/index.html 19913 9. mailto:gcc (a] gcc.gnu.org 19914 10. https://gcc.gnu.org/onlinedocs/ 19915 11. mailto:gcc-help (a] gcc.gnu.org 19916 12. mailto:gcc (a] gcc.gnu.org 19917 13. https://gcc.gnu.org/lists.html 19918 14. https://www.fsf.org/ 19919 15. https://gcc.gnu.org/about.html 19920 ====================================================================== 19921 http://gcc.gnu.org/gcc-2.95/features.html 19922 19923 GCC 2.95 New Features 19924 19925 * General Optimizer Improvements: 19926 + [1]Localized register spilling to improve speed and code 19927 density especially on small register class machines. 19928 + [2]Global CSE using lazy code motion algorithms. 19929 + [3]Improved global constant/copy propagation. 19930 + [4]Improved control flow graph analysis and manipulation. 19931 + [5]Local dead store elimination. 19932 + [6]Memory Load hoisting/store sinking in loops. 19933 + [7]Type based alias analysis is enabled by default. Note this 19934 feature will expose bugs in the Linux kernel. Please refer to 19935 the FAQ (as shipped with GCC 2.95) for additional information 19936 on this issue. 19937 + Major revamp of GIV detection, combination and simplification 19938 to improve loop performance. 19939 + Major improvements to register allocation and reloading. 19940 * New Languages and Language specific improvements 19941 + [8]Many C++ improvements. 19942 + [9]Many Fortran improvements. 19943 + [10]Java front-end has been integrated. A [11]runtime library 19944 is available separately. 19945 + [12]ISO C99 support 19946 + [13]Chill front-end and runtime has been integrated. 19947 + Boehm garbage collector support in libobjc. 19948 + More support for various pragmas which appear in vendor 19949 include files 19950 * New Targets and Target Specific Improvements 19951 + [14]SPARC backend rewrite. 19952 + -mschedule=8000 will optimize code for PA8000 class 19953 processors; -mpa-risc-2-0 will generate code for PA2.0 19954 processors 19955 + Various micro-optimizations for the ia32 port. K6 19956 optimizations 19957 + Compiler will attempt to align doubles in the stack on the 19958 ia32 port 19959 + Alpha EV6 support 19960 + PowerPC 750 19961 + RS6000/PowerPC: -mcpu=401 was added as an alias for -mcpu=403. 19962 -mcpu=e603e was added to do -mcpu=603e and -msoft-float. 19963 + c3x, c4x 19964 + HyperSPARC 19965 + SparcLite86x 19966 + sh4 19967 + Support for new systems (OpenBSD, FreeBSD, UWIN, Interix, 19968 arm-linux) 19969 + vxWorks targets include support for vxWorks threads 19970 + StrongARM 110 and ARM9 support added. ARM Scheduling 19971 parameters rewritten. 19972 + Various changes to the MIPS port to avoid assembler macros, 19973 which in turn improves performance 19974 + Various performance improvements to the i960 port. 19975 + Major rewrite of ns32k port 19976 * Other significant improvements 19977 + [15]Ability to dump cfg information and display it using vcg. 19978 + The new faster scheme for fixing vendor header files is 19979 enabled by default. 19980 + Experimental internationalization support. 19981 + multibyte character support 19982 + Some compile-time speedups for pathological problems 19983 + Better support for complex types 19984 * Plus the usual mountain of bugfixes 19985 * Core compiler is based on the gcc2 development tree from Sept 30, 19986 1998, so we have all of the [16]features found in GCC 2.8. 19987 19988 Additional Changes in GCC 2.95.1 19989 19990 * Generic bugfixes and improvements 19991 + Various documentation fixes related to the GCC/EGCS merger. 19992 + Fix memory management bug which could lead to spurious aborts, 19993 core dumps or random parsing errors in the compiler. 19994 + Fix a couple bugs in the dwarf1 and dwarf2 debug record 19995 support. 19996 + Fix infinite loop in the CSE optimizer. 19997 + Avoid undefined behavior in compiler FP emulation code 19998 + Fix install problem when prefix is overridden on the make 19999 install command. 20000 + Fix problem with unwanted installation of assert.h on some 20001 systems. 20002 + Fix problem with finding the wrong assembler in a single tree 20003 build. 20004 + Avoid increasing the known alignment of a register that is 20005 already known to be a pointer. 20006 * Platform specific bugfixes and improvements 20007 + Codegen bugfix for prologue/epilogue for cpu32 target. 20008 + Fix long long code generation bug for the Coldfire target. 20009 + Fix various aborts in the SH compiler. 20010 + Fix bugs in libgcc support library for the SH. 20011 + Fix alpha ev6 code generation bug. 20012 + Fix problems with EXIT_SUCCESS/EXIT_FAILURE redefinitions on 20013 AIX platforms. 20014 + Fix -fpic code generation bug for rs6000/ppc svr4 targets. 20015 + Fix varargs/stdarg code generation bug for rs6000/ppc svr4 20016 targets. 20017 + Fix weak symbol handling for rs6000/ppc svr4 targets. 20018 + Fix various problems with 64bit code generation for the 20019 rs6000/ppc port. 20020 + Fix codegen bug which caused tetex to be mis-compiled on the 20021 x86. 20022 + Fix compiler abort in new cfg code exposed by x86 port. 20023 + Fix out of range array reference in code convert flat 20024 registers to the x87 stacked FP register file. 20025 + Fix minor vxworks configuration bug. 20026 + Fix return type of bsearch for SunOS 4.x. 20027 * Language & Runtime specific fixes. 20028 + The G++ signature extension has been deprecated. It will be 20029 removed in the next major release of G++. Use of signatures 20030 will result in a warning from the compiler. 20031 + Several bugs relating to templates and namespaces were fixed. 20032 + A bug that caused crashes when combining templates with -g on 20033 DWARF1 platforms was fixed. 20034 + Pointers-to-members, virtual functions, and multiple 20035 inheritance should now work together correctly. 20036 + Some code-generation bugs relating to function try blocks were 20037 fixed. 20038 + G++ is a little bit more lenient with certain archaic 20039 constructs than in GCC 2.95. 20040 + Fix to prevent shared library version #s from bring truncated 20041 to 1 digit 20042 + Fix missing std:: in the libstdc++ library. 20043 + Fix stream locking problems in libio. 20044 + Fix problem in java compiler driver. 20045 20046 Additional Changes in GCC 2.95.2 20047 20048 The -fstrict-aliasing is not enabled by default for GCC 2.95.2. While 20049 the optimizations performed by -fstrict-aliasing are valid according to 20050 the C and C++ standards, the optimization have caused some problems, 20051 particularly with old non-conforming code. 20052 20053 The GCC developers are experimenting with ways to warn users about code 20054 which violates the C/C++ standards, but those warnings are not ready 20055 for widespread use at this time. Rather than wait for those warnings 20056 the GCC developers have chosen to disable -fstrict-aliasing by default 20057 for the GCC 2.95.2 release. 20058 20059 We strongly encourage developers to find and fix code which violates 20060 the C/C++ standards as -fstrict-aliasing may be enabled by default in 20061 future releases. Use the option -fstrict-aliasing to re-enable these 20062 optimizations. 20063 * Generic bugfixes and improvements 20064 + Fix incorrectly optimized memory reference in global common 20065 subexpression elimination (GCSE) optimization pass. 20066 + Fix code generation bug in regmove.c in which it could 20067 incorrectly change a "const" value. 20068 + Fix bug in optimization of conditionals involving volatile 20069 memory references. 20070 + Avoid over-allocation of stack space for some procedures. 20071 + Fixed bug in the compiler which caused incorrect optimization 20072 of an obscure series of bit manipulations, shifts and 20073 arithmetic. 20074 + Fixed register allocator bug which caused teTeX to be 20075 mis-compiled on SPARC targets. 20076 + Avoid incorrect optimization of degenerate case statements for 20077 certain targets such as the ARM. 20078 + Fix out of range memory reference in the jump optimizer. 20079 + Avoid dereferencing null pointer in fix-header. 20080 + Fix test for GCC specific features so that it is possible to 20081 bootstrap with gcc-2.6.2 and older versions of GCC. 20082 + Fix typo in scheduler which could potentially cause out of 20083 range memory accesses. 20084 + Avoid incorrect loop reversal which caused incorrect code for 20085 certain loops on PowerPC targets. 20086 + Avoid incorrect optimization of switch statements on certain 20087 targets (for example the ARM). 20088 * Platform specific bugfixes and improvements 20089 + Work around bug in Sun V5.0 compilers which caused bootstrap 20090 comparison failures on SPARC targets. 20091 + Fix SPARC backend bug which caused aborts in final.c. 20092 + Fix sparc-hal-solaris2* configuration fragments. 20093 + Fix bug in sparc block profiling. 20094 + Fix obscure code generation bug for the PARISC targets. 20095 + Define __STDC_EXT__ for HPUX configurations. 20096 + Various POWERPC64 code generation bugfixes. 20097 + Fix abort for PPC targets using ELF (ex GNU/Linux). 20098 + Fix collect2 problems for AIX targets. 20099 + Correct handling of .file directive for PPC targets. 20100 + Fix bug in fix_trunc x86 patterns. 20101 + Fix x86 port to correctly pop the FP stack for functions that 20102 return structures in memory. 20103 + Fix minor bug in strlen x86 pattern. 20104 + Use stabs debugging instead of dwarf1 for x86-solaris targets. 20105 + Fix template repository code to handle leading underscore in 20106 mangled names. 20107 + Fix weak/weak alias support for OpenBSD. 20108 + GNU/Linux for the ARM has C++ compatible include files. 20109 * Language & Runtime specific fixes. 20110 + Fix handling of constructor attribute in the C front-end which 20111 caused problems building the Chill runtime library on some 20112 targets. 20113 + Fix minor problem merging type qualifiers in the C front-end. 20114 + Fix aliasing bug for pointers and references (C/C++). 20115 + Fix incorrect "non-constant initializer bug" when -traditional 20116 or -fwritable-strings is enabled. 20117 + Fix build error for Chill front-end on SunOS. 20118 + Do not complain about duplicate instantiations when using 20119 -frepo (C++). 20120 + Fix array bounds handling in C++ front-end which caused 20121 problems with dwarf debugging information in some 20122 circumstances. 20123 + Fix minor namespace problem. 20124 + Fix problem linking java programs. 20125 20126 Additional Changes in GCC 2.95.3 20127 20128 * Generic bugfixes and improvements 20129 + Fix numerous problems that caused incorrect optimization in 20130 the register reloading code. 20131 + Fix numerous problems that caused incorrect optimization in 20132 the loop optimizer. 20133 + Fix aborts in the functions build_insn_chain and scan_loops 20134 under some circumstances. 20135 + Fix an alias analysis bug. 20136 + Fix an infinite compilation bug in the combiner. 20137 + A few problems with complex number support have been fixed. 20138 + It is no longer possible for gcc to act as a fork bomb when 20139 installed incorrectly. 20140 + The -fpack-struct option should be recognized now. 20141 + Fixed a bug that caused incorrect code to be generated due to 20142 a lost stack adjustment. 20143 * Platform specific bugfixes and improvements 20144 + Support building ARM toolchains hosted on Windows. 20145 + Fix attribute calculations in ARM toolchains. 20146 + arm-linux support has been improved. 20147 + Fix a PIC failure on sparc targets. 20148 + On ix86 targets, the regparm attribute should now work 20149 reliably. 20150 + Several updates for the h8300 port. 20151 + Fix problem building libio with glibc 2.2. 20152 20153 20154 For questions related to the use of GCC, please consult these web 20155 pages and the [17]GCC manuals. If that fails, the 20156 [18]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20157 web pages and the development of GCC are welcome on our developer 20158 list at [19]gcc (a] gcc.gnu.org. All of [20]our lists have public 20159 archives. 20160 20161 Copyright (C) [21]Free Software Foundation, Inc. Verbatim copying and 20162 distribution of this entire article is permitted in any medium, 20163 provided this notice is preserved. 20164 20165 These pages are [22]maintained by the GCC team. Last modified 20166 2022-10-26. 20167 20168 References 20169 20170 1. http://gcc.gnu.org/news/spill.html 20171 2. http://gcc.gnu.org/news/lcm.html 20172 3. http://gcc.gnu.org/news/cprop.html 20173 4. http://gcc.gnu.org/news/cfg.html 20174 5. http://gcc.gnu.org/news/dse.html 20175 6. http://gcc.gnu.org/news/hoist.html 20176 7. http://gcc.gnu.org/news/alias.html 20177 8. http://gcc.gnu.org/gcc-2.95/c++features.html 20178 9. https://gcc.gnu.org/onlinedocs/gcc-3.4.6/g77/News.html 20179 10. http://gcc.gnu.org/news/gcj-announce.txt 20180 11. http://gcc.gnu.org/news/javaannounce.html 20181 12. http://gcc.gnu.org/c99status.html 20182 13. http://gcc.gnu.org/news/chill.html 20183 14. http://gcc.gnu.org/news/sparc.html 20184 15. http://gcc.gnu.org/news/egcs-vcg.html 20185 16. http://gcc.gnu.org/egcs-1.0/features-2.8.html 20186 17. https://gcc.gnu.org/onlinedocs/ 20187 18. mailto:gcc-help (a] gcc.gnu.org 20188 19. mailto:gcc (a] gcc.gnu.org 20189 20. https://gcc.gnu.org/lists.html 20190 21. https://www.fsf.org/ 20191 22. https://gcc.gnu.org/about.html 20192 ====================================================================== 20193 http://gcc.gnu.org/gcc-2.95/caveats.html 20194 20195 GCC 2.95 Caveats 20196 20197 * GCC 2.95 will issue an error for invalid asm statements that had 20198 been silently accepted by earlier versions of the compiler. This is 20199 particularly noticeable when compiling older versions of the Linux 20200 kernel (2.0.xx). Please refer to the FAQ (as shipped with GCC 2.95) 20201 for more information on this issue. 20202 * GCC 2.95 implements type based alias analysis to disambiguate 20203 memory references. Some programs, particularly the Linux kernel 20204 violate ANSI/ISO aliasing rules and therefore may not operate 20205 correctly when compiled with GCC 2.95. Please refer to the FAQ (as 20206 shipped with GCC 2.95) for more information on this issue. 20207 * GCC 2.95 has a known bug in its handling of complex variables for 20208 64bit targets. Instead of silently generating incorrect code, GCC 20209 2.95 will issue a fatal error for situations it can not handle. 20210 This primarily affects the Fortran community as Fortran makes more 20211 use of complex variables than C or C++. 20212 * GCC 2.95 has an integrated libstdc++, but does not have an 20213 integrated libg++. Furthermore old libg++ releases will not work 20214 with GCC 2.95. You can retrieve a recent copy of libg++ from the 20215 [1]GCC ftp server. 20216 Note most C++ programs only need libstdc++. 20217 * Exception handling may not work with shared libraries, particularly 20218 on alphas, hppas, rs6000/powerpc and mips based platforms. 20219 Exception handling is known to work on x86 GNU/Linux platforms with 20220 shared libraries. 20221 * In general, GCC 2.95 is more rigorous about rejecting invalid C++ 20222 code or deprecated C++ constructs than G++ 2.7, G++ 2.8, EGCS 1.0, 20223 or EGCS 1.1. As a result it may be necessary to fix C++ code before 20224 it will compile with GCC 2.95. 20225 * G++ is also converting toward the ISO C++ standard; as a result 20226 code which was previously valid (and thus accepted by other 20227 compilers and older versions of g++) may no longer be accepted. The 20228 flag -fpermissive may allow some non-conforming code to compile 20229 with GCC 2.95. 20230 * GCC 2.95 compiled C++ code is not binary compatible with EGCS 20231 1.1.x, EGCS 1.0.x or GCC 2.8.x. 20232 * GCC 2.95 does not have changes from the GCC 2.8 tree that were made 20233 between Sept 30, 1998 and April 30, 1999 (the official end of the 20234 GCC 2.8 project). Future GCC releases will include all the changes 20235 from the defunct GCC 2.8 sources. 20236 20237 20238 For questions related to the use of GCC, please consult these web 20239 pages and the [2]GCC manuals. If that fails, the 20240 [3]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20241 web pages and the development of GCC are welcome on our developer 20242 list at [4]gcc (a] gcc.gnu.org. All of [5]our lists have public archives. 20243 20244 Copyright (C) [6]Free Software Foundation, Inc. Verbatim copying and 20245 distribution of this entire article is permitted in any medium, 20246 provided this notice is preserved. 20247 20248 These pages are [7]maintained by the GCC team. Last modified 20249 2022-10-26. 20250 20251 References 20252 20253 1. ftp://gcc.gnu.org/pub/gcc/infrastructure/libg++-2.8.1.3.tar.gz 20254 2. https://gcc.gnu.org/onlinedocs/ 20255 3. mailto:gcc-help (a] gcc.gnu.org 20256 4. mailto:gcc (a] gcc.gnu.org 20257 5. https://gcc.gnu.org/lists.html 20258 6. https://www.fsf.org/ 20259 7. https://gcc.gnu.org/about.html 20260 ====================================================================== 20261 http://gcc.gnu.org/egcs-1.1/index.html 20262 20263 EGCS 1.1 20264 20265 September 3, 1998: We are pleased to announce the release of EGCS 1.1. 20266 December 1, 1998: We are pleased to announce the release of EGCS 1.1.1. 20267 March 15, 1999: We are pleased to announce the release of EGCS 1.1.2. 20268 20269 EGCS is a free software project to further the development of the GNU 20270 compilers using an open development environment. 20271 20272 EGCS 1.1 is a major new release of the EGCS compiler system. It has 20273 been [1]extensively tested and is believed to be stable and suitable 20274 for widespread use. 20275 20276 EGCS 1.1 is based on an June 6, 1998 snapshot of the GCC 2.8 20277 development sources; it contains all of the new features found in GCC 20278 2.8.1 as well as all new development from GCC up to June 6, 1998. 20279 20280 EGCS 1.1 also contains many improvements and features not found in GCC 20281 or in older versions of EGCS: 20282 * Global common subexpression elimination and global constant/copy 20283 propagation (aka [2]gcse) 20284 * Ongoing improvements to the [3]alias analysis support to allow for 20285 better optimizations throughout the compiler. 20286 * Vastly improved [4]C++ compiler and integrated C++ runtime 20287 libraries. 20288 * Fixes for the /tmp symlink race security problems. 20289 * New targets including mips16, arm-thumb and 64 bit PowerPC. 20290 * Improvements to GNU Fortran (g77) compiler and runtime library made 20291 since g77 version 0.5.23. 20292 20293 See the [5]new features page for a more complete list of new features 20294 found in EGCS 1.1 releases. 20295 20296 EGCS 1.1.1 is a minor update to fix several serious problems in EGCS 20297 1.1: 20298 * General improvements and fixes 20299 + Avoid some stack overflows when compiling large functions. 20300 + Avoid incorrect loop invariant code motions. 20301 + Fix some core dumps on Linux kernel code. 20302 + Bring back the imake -Di386 and friends fix from EGCS 1.0.2. 20303 + Fix code generation problem in gcse. 20304 + Various documentation related fixes. 20305 * g++/libstdc++ improvements and fixes 20306 + MT safe EH fix for setjmp/longjmp based exception handling. 20307 + Fix a few bad interactions between optimization and exception 20308 handling. 20309 + Fixes for demangling of template names starting with "__". 20310 + Fix a bug that would fail to run destructors in some cases 20311 with -O2. 20312 + Fix 'new' of classes with virtual bases. 20313 + Fix crash building Qt on the Alpha. 20314 + Fix failure compiling WIFEXITED macro on GNU/Linux. 20315 + Fix some -frepo failures. 20316 * g77 and libf2c improvements and fixes 20317 + Various documentation fixes. 20318 + Avoid compiler crash on RAND intrinsic. 20319 + Fix minor bugs in makefiles exposed by BSD make programs. 20320 + Define _XOPEN_SOURCE for libI77 build to avoid potential 20321 problems on some 64-bit systems. 20322 + Fix problem with implicit endfile on rewind. 20323 + Fix spurious recursive I/O errors. 20324 * platform specific improvements and fixes 20325 + Match all versions of UnixWare7. 20326 + Do not assume x86 SVR4 or UnixWare targets can handle stabs. 20327 + Fix PPC/RS6000 LEGITIMIZE_ADDRESS macro and bug in conversion 20328 from unsigned ints to double precision floats. 20329 + Fix ARM ABI issue with NetBSD. 20330 + Fix a few arm code generation bugs. 20331 + Fixincludes will fix additional broken SCO OpenServer header 20332 files. 20333 + Fix a m68k backend bug which caused invalid offsets in reg+d 20334 addresses. 20335 + Fix problems with 64bit AIX 4.3 support. 20336 + Fix handling of long longs for varargs/stdarg functions on the 20337 ppc. 20338 + Minor fixes to CPP predefines for Windows. 20339 + Fix code generation problems with gpr<->fpr copies for 64bit 20340 ppc. 20341 + Fix a few coldfire code generation bugs. 20342 + Fix some more header file problems on SunOS 4.x. 20343 + Fix assert.h handling for RTEMS. 20344 + Fix Windows handling of TREE_SYMBOL_REFERENCED. 20345 + Fix x86 compiler abort in reg-stack pass. 20346 + Fix cygwin/windows problem with section attributes. 20347 + Fix Alpha code generation problem exposed by SMP Linux 20348 kernels. 20349 + Fix typo in m68k 32->64bit integer conversion. 20350 + Make sure target libraries build with -fPIC for PPC & Alpha 20351 targets. 20352 20353 EGCS 1.1.2 is a minor update to fix several serious problems in EGCS 20354 1.1.1: 20355 * General improvements and fixes 20356 + Fix bug in loop optimizer which caused the SPARC (and 20357 potentially other) ports to segfault. 20358 + Fix infinite recursion in alias analysis and combiner code. 20359 + Fix bug in regclass preferencing. 20360 + Fix incorrect loop reversal which caused incorrect code to be 20361 generated for several targets. 20362 + Fix return value for builtin memcpy. 20363 + Reduce compile time for certain loops which exposed quadratic 20364 behavior in the loop optimizer. 20365 + Fix bug which caused volatile memory to be written multiple 20366 times when only one write was needed/desired. 20367 + Fix compiler abort in caller-save.c 20368 + Fix combiner bug which caused incorrect code generation for 20369 certain division by constant operations. 20370 + Fix incorrect code generation due to a bug in range check 20371 optimizations. 20372 + Fix incorrect code generation due to mis-handling of clobbered 20373 values in CSE. 20374 + Fix compiler abort/segfault due to incorrect register 20375 splitting when unrolling loops. 20376 + Fix code generation involving autoincremented addresses with 20377 ternary operators. 20378 + Work around bug in the scheduler which caused qt to be 20379 mis-compiled on some platforms. 20380 + Fix code generation problems with -fshort-enums. 20381 + Tighten security for temporary files. 20382 + Improve compile time for codes which make heavy use of 20383 overloaded functions. 20384 + Fix multiply defined constructor/destructor symbol problems. 20385 + Avoid setting bogus RPATH environment variable during 20386 bootstrap. 20387 + Avoid GNU-make dependencies in the texinfo subdir. 20388 + Install CPP wrapper script in $(prefix)/bin if --enable-cpp. 20389 --enable-cpp=<dirname> can be used to specify an additional 20390 install directory for the cpp wrapper script. 20391 + Fix CSE bug which caused incorrect label-label refs to appear 20392 on some platforms. 20393 + Avoid linking in EH routines from libgcc if they are not 20394 needed. 20395 + Avoid obscure bug in aliasing code. 20396 + Fix bug in weak symbol handling. 20397 * Platform-specific improvements and fixes 20398 + Fix detection of PPro/PII on Unixware 7. 20399 + Fix compiler segfault when building spec99 and other programs 20400 for SPARC targets. 20401 + Fix code-generation bugs for integer and floating point 20402 conditional move instructions on the PPro/PII. 20403 + Use fixincludes to fix byteorder problems on i?86-*-sysv. 20404 + Fix build failure for the arc port. 20405 + Fix floating point format configuration for i?86-gnu port. 20406 + Fix problems with hppa1.0-hp-hpux10.20 configuration when 20407 threads are enabled. 20408 + Fix coldfire code generation bugs. 20409 + Fix "unrecognized insn" problems for Alpha and PPC ports. 20410 + Fix h8/300 code generation problem with floating point values 20411 in memory. 20412 + Fix unrecognized insn problems for the m68k port. 20413 + Fix namespace-pollution problem for the x86 port. 20414 + Fix problems with old assembler on x86 NeXT systems. 20415 + Fix PIC code-generation problems for the SPARC port. 20416 + Fix minor bug with LONG_CALLS in PowerPC SVR4 support. 20417 + Fix minor ISO namespace violation in Alpha varargs/stdarg 20418 support. 20419 + Fix incorrect "braf" instruction usage for the SH port. 20420 + Fix minor bug in va-sh which prevented its use with -ansi. 20421 + Fix problems recognizing and supporting FreeBSD. 20422 + Handle OpenBSD systems correctly. 20423 + Minor fixincludes fix for Digital UNIX 4.0B. 20424 + Fix problems with ctors/dtors in SCO shared libraries. 20425 + Abort instead of generating incorrect code for PPro/PII 20426 floating point conditional moves. 20427 + Avoid multiply defined symbols on GNU/Linux systems using 20428 libc-5.4.xx. 20429 + Fix abort in alpha compiler. 20430 * Fortran-specific fixes 20431 + Fix the IDate intrinsic (VXT) (in libg2c) so the returned year 20432 is in the documented, non-Y2K-compliant range of 0-99, instead 20433 of being returned as 100 in the year 2000. 20434 + Fix the `Date_and_Time' intrinsic (in libg2c) to return the 20435 milliseconds value properly in Values(8). 20436 + Fix the `LStat' intrinsic (in libg2c) to return device-ID 20437 information properly in SArray(7). 20438 20439 Each release includes installation instructions in both HTML and 20440 plaintext forms (see the INSTALL directory in the toplevel directory of 20441 the distribution). However, we also keep the most up to date 20442 installation instructions and [6]build/test status on our web page. We 20443 will update those pages as new information becomes available. 20444 20445 The EGCS project would like to thank the numerous people that have 20446 contributed new features, test results, bugfixes, etc. This [7]amazing 20447 group of volunteers is what makes EGCS successful. 20448 20449 And finally, we can't in good conscience fail to mention some 20450 [8]caveats to using EGCS 1.1. 20451 20452 Download EGCS from egcs.cygnus.com (USA California). 20453 20454 The EGCS 1.1 release is also available on many mirror sites. 20455 [9]Goto mirror list to find a closer site. 20456 20457 20458 For questions related to the use of GCC, please consult these web 20459 pages and the [10]GCC manuals. If that fails, the 20460 [11]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20461 web pages and the development of GCC are welcome on our developer 20462 list at [12]gcc (a] gcc.gnu.org. All of [13]our lists have public 20463 archives. 20464 20465 Copyright (C) [14]Free Software Foundation, Inc. Verbatim copying and 20466 distribution of this entire article is permitted in any medium, 20467 provided this notice is preserved. 20468 20469 These pages are [15]maintained by the GCC team. Last modified 20470 2023-01-21. 20471 20472 References 20473 20474 1. http://gcc.gnu.org/egcs-1.1/egcs-1.1-test.html 20475 2. http://gcc.gnu.org/news/gcse.html 20476 3. http://gcc.gnu.org/news/alias.html 20477 4. http://gcc.gnu.org/egcs-1.1/c++features.html 20478 5. http://gcc.gnu.org/egcs-1.1/features.html 20479 6. http://gcc.gnu.org/egcs-1.1/buildstat.html 20480 7. https://gcc.gnu.org/onlinedocs/gcc/Contributors.html 20481 8. http://gcc.gnu.org/egcs-1.1/caveats.html 20482 9. http://gcc.gnu.org/mirrors.html 20483 10. https://gcc.gnu.org/onlinedocs/ 20484 11. mailto:gcc-help (a] gcc.gnu.org 20485 12. mailto:gcc (a] gcc.gnu.org 20486 13. https://gcc.gnu.org/lists.html 20487 14. https://www.fsf.org/ 20488 15. https://gcc.gnu.org/about.html 20489 ====================================================================== 20490 http://gcc.gnu.org/egcs-1.1/features.html 20491 20492 EGCS 1.1 new features 20493 20494 * Integrated GNU Fortran (g77) compiler and runtime library with 20495 improvements, based on g77 version 0.5.23. 20496 * Vast improvements in the C++ compiler; so many they have [1]page of 20497 their own! 20498 * Compiler implements [2]global common subexpression elimination and 20499 global copy/constant propagation. 20500 * More major improvements in the [3]alias analysis code. 20501 * More major improvements in the exception handling code to improve 20502 performance, lower static overhead and provide the infrastructure 20503 for future improvements. 20504 * The infamous /tmp symlink race security problems have been fixed. 20505 * The regmove optimization pass has been nearly completely rewritten 20506 to improve performance of generated code. 20507 * The compiler now recomputes register usage information before local 20508 register allocation. By providing more accurate information to the 20509 priority based allocator, we get better register allocation. 20510 * The register reloading phase of the compiler optimizes spill code 20511 much better than in previous releases. 20512 * Some bad interactions between the register allocator and 20513 instruction scheduler have been fixed, resulting in much better 20514 code for certain programs. Additionally, we have tuned the 20515 scheduler in various ways to improve performance of generated code 20516 for some architectures. 20517 * The compiler's branch shortening algorithms have been significantly 20518 improved to work better on targets which align jump targets. 20519 * The compiler now supports -Os to prefer optimizing for code space 20520 over optimizing for code speed. 20521 * The compiler will now totally eliminate library calls which compute 20522 constant values. This primarily helps targets with no integer 20523 div/mul support and targets without floating point support. 20524 * The compiler now supports an extensive "--help" option. 20525 * cpplib has been greatly improved and may be suitable for limited 20526 use. 20527 * Memory footprint for the compiler has been significantly reduced 20528 for some pathological cases. 20529 * The time to build EGCS has been improved for certain targets 20530 (particularly the alpha and mips platforms). 20531 * Many infrastructure improvements throughout the compiler, plus the 20532 usual mountain of bugfixes and minor improvements. 20533 * Target dependent improvements: 20534 + SPARC port now includes V8 plus and V9 support as well as 20535 performance tuning for Ultra class machines. The SPARC port 20536 now uses the Haifa scheduler. 20537 + Alpha port has been tuned for the EV6 processor and has an 20538 optimized expansion of memcpy/bzero. The Alpha port now uses 20539 the Haifa scheduler. 20540 + RS6000/PowerPC: support for the Power64 architecture and AIX 20541 4.3. The RS6000/PowerPC port now uses the Haifa scheduler. 20542 + x86: Alignment of static store data and jump targets is per 20543 Intel recommendations now. Various improvements throughout the 20544 x86 port to improve performance on Pentium processors 20545 (including improved epilogue sequences for Pentium chips and 20546 backend improvements which should help register allocation on 20547 all x86 variants. Conditional move support has been fixed and 20548 enabled for PPro processors. The x86 port also better supports 20549 64bit operations now. Unixware 7, a System V Release 5 target, 20550 is now supported and SCO OpenServer targets can support GAS. 20551 + MIPS has improved multiply/multiply-add support and now 20552 includes mips16 ISA support. 20553 + M68k has many micro-optimizations and Coldfire fixes. 20554 * Core compiler is based on the GCC development tree from June 9, 20555 1998, so we have all of the [4]features found in GCC 2.8. 20556 20557 20558 For questions related to the use of GCC, please consult these web 20559 pages and the [5]GCC manuals. If that fails, the 20560 [6]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20561 web pages and the development of GCC are welcome on our developer 20562 list at [7]gcc (a] gcc.gnu.org. All of [8]our lists have public archives. 20563 20564 Copyright (C) [9]Free Software Foundation, Inc. Verbatim copying and 20565 distribution of this entire article is permitted in any medium, 20566 provided this notice is preserved. 20567 20568 These pages are [10]maintained by the GCC team. Last modified 20569 2022-10-26. 20570 20571 References 20572 20573 1. http://gcc.gnu.org/egcs-1.1/c++features.html 20574 2. http://gcc.gnu.org/news/gcse.html 20575 3. http://gcc.gnu.org/news/alias.html 20576 4. http://gcc.gnu.org/egcs-1.0/features-2.8.html 20577 5. https://gcc.gnu.org/onlinedocs/ 20578 6. mailto:gcc-help (a] gcc.gnu.org 20579 7. mailto:gcc (a] gcc.gnu.org 20580 8. https://gcc.gnu.org/lists.html 20581 9. https://www.fsf.org/ 20582 10. https://gcc.gnu.org/about.html 20583 ====================================================================== 20584 http://gcc.gnu.org/egcs-1.1/caveats.html 20585 20586 EGCS 1.1 Caveats 20587 20588 * EGCS has an integrated libstdc++, but does not have an integrated 20589 libg++. Furthermore old libg++ releases will not work with EGCS; HJ 20590 Lu has made a libg++-2.8.1.2 snapshot available which may work with 20591 EGCS. 20592 Note most C++ programs only need libstdc++. 20593 * Exception handling may not work with shared libraries, particularly 20594 on alphas, hppas, rs6000/powerpc and mips based platforms. 20595 Exception handling is known to work on x86-linux platforms with 20596 shared libraries. 20597 * Some versions of the Linux kernel have bugs which prevent them from 20598 being compiled or from running when compiled by EGCS. See the FAQ 20599 (as shipped with EGCS 1.1) for additional information. 20600 * In general, EGCS is more rigorous about rejecting invalid C++ code 20601 or deprecated C++ constructs than g++-2.7, g++-2.8 or EGCS 1.0. As 20602 a result it may be necessary to fix C++ code before it will compile 20603 with EGCS. 20604 * G++ is also converting toward the ISO C++ standard; as a result 20605 code which was previously valid (and thus accepted by other 20606 compilers and older versions of g++) may no longer be accepted. 20607 * EGCS 1.1 compiled C++ code is not binary compatible with EGCS 1.0.x 20608 or GCC 2.8.x due to changes necessary to support thread safe 20609 exception handling. 20610 20611 20612 For questions related to the use of GCC, please consult these web 20613 pages and the [1]GCC manuals. If that fails, the 20614 [2]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20615 web pages and the development of GCC are welcome on our developer 20616 list at [3]gcc (a] gcc.gnu.org. All of [4]our lists have public archives. 20617 20618 Copyright (C) [5]Free Software Foundation, Inc. Verbatim copying and 20619 distribution of this entire article is permitted in any medium, 20620 provided this notice is preserved. 20621 20622 These pages are [6]maintained by the GCC team. Last modified 20623 2022-10-26. 20624 20625 References 20626 20627 1. https://gcc.gnu.org/onlinedocs/ 20628 2. mailto:gcc-help (a] gcc.gnu.org 20629 3. mailto:gcc (a] gcc.gnu.org 20630 4. https://gcc.gnu.org/lists.html 20631 5. https://www.fsf.org/ 20632 6. https://gcc.gnu.org/about.html 20633 ====================================================================== 20634 http://gcc.gnu.org/egcs-1.0/index.html 20635 20636 EGCS 1.0 20637 20638 December 3, 1997: We are pleased to announce the release of EGCS 1.0. 20639 January 6, 1998: We are pleased to announce the release of EGCS 1.0.1. 20640 March 16, 1998: We are pleased to announce the release of EGCS 1.0.2. 20641 May 15, 1998 We are pleased to announce the release of EGCS 1.0.3. 20642 20643 EGCS is a collaborative effort involving several groups of hackers 20644 using an open development model to accelerate development and testing 20645 of GNU compilers and runtime libraries. 20646 20647 An important goal of EGCS is to allow wide scale testing of 20648 experimental features and optimizations; therefore, EGCS contains some 20649 features and optimizations which are still under development. However, 20650 EGCS has been carefully tested and should be comparable in quality to 20651 most GCC releases. 20652 20653 EGCS 1.0 is based on an August 2, 1997 snapshot of the GCC 2.8 20654 development sources; it contains nearly all of the new features found 20655 in GCC 2.8. 20656 20657 EGCS 1.0 also contains many improvements and features not found in GCC 20658 2.7 and even the GCC 2.8 series (which was released after the original 20659 EGCS 1.0 release). 20660 * Integrated C++ runtime libraries, including support for most major 20661 GNU/Linux systems! 20662 * The integrated libstdc++ library includes a verbatim copy of SGI's 20663 STL release. 20664 * Integrated GNU Fortran compiler. 20665 * New instruction scheduler. 20666 * New alias analysis code. 20667 20668 See the [1]new features page for a more complete list of new features. 20669 20670 EGCS 1.0.1 is a minor update to the EGCS 1.0 compiler to fix a few 20671 critical bugs and add support for Red Hat 5.0 Linux. Changes since the 20672 EGCS 1.0 release: 20673 * Add support for Red Hat 5.0 Linux and better support for Linux 20674 systems using glibc2. 20675 Many programs failed to link when compiled with EGCS 1.0 on Red Hat 20676 5.0 or on systems with newer versions of glibc2. EGCS 1.0.1 should 20677 fix these problems. 20678 * Compatibility with both EGCS 1.0 and GCC 2.8 libgcc exception 20679 handling interfaces. 20680 To avoid future compatibility problems, we strongly urge anyone who 20681 is planning on distributing shared libraries that contain C++ code 20682 to upgrade to EGCS 1.0.1 first. 20683 Soon after EGCS 1.0 was released, the GCC developers made some 20684 incompatible changes in libgcc's exception handling interfaces. 20685 These changes were needed to solve problems on some platforms. This 20686 means that GCC 2.8.0, when released, will not be seamlessly 20687 compatible with shared libraries built by EGCS 1.0. The reason is 20688 that the libgcc.a in GCC 2.8.0 will not contain a function needed 20689 by the old interface. 20690 The result of this is that there may be compatibility problems with 20691 shared libraries built by EGCS 1.0 when used with GCC 2.8.0. 20692 With EGCS 1.0.1, generated code uses the new (GCC 2.8.0) interface, 20693 and libgcc.a has the support routines for both the old and the new 20694 interfaces (so EGCS 1.0.1 and EGCS 1.0 code can be freely mixed, 20695 and EGCS 1.0.1 and GCC 2.8.0 code can be freely mixed). 20696 The maintainers of GCC 2.x have decided against including seamless 20697 support for the old interface in 2.8.0, since it was never 20698 "official", so to avoid future compatibility problems we recommend 20699 against distributing any shared libraries built by EGCS 1.0 that 20700 contain C++ code (upgrade to 1.0.1 and use that). 20701 * Various bugfixes in the x86, hppa, mips, and rs6000/ppc back ends. 20702 The x86 changes fix code generation errors exposed when building 20703 glibc2 and the usual GNU/Linux dynamic linker (ld.so). 20704 The hppa change fixes a compiler abort when configured for use with 20705 RTEMS. 20706 The MIPS changes fix problems with the definition of LONG_MAX on 20707 newer systems, allow for command line selection of the target ABI, 20708 and fix one code generation problem. 20709 The rs6000/ppc change fixes some problems with passing structures 20710 to varargs/stdarg functions. 20711 * A few machine independent bugfixes, mostly to fix code generation 20712 errors when building Linux kernels or glibc. 20713 * Fix a few critical exception handling and template bugs in the C++ 20714 compiler. 20715 * Fix Fortran namelist bug on alphas. 20716 * Fix build problems on x86-solaris systems. 20717 20718 EGCS 1.0.2 is a minor update to the EGCS 1.0.1 compiler to fix several 20719 serious problems in EGCS 1.0.1. 20720 * General improvements and fixes 20721 + Memory consumption significantly reduced, especially for 20722 templates and inline functions. 20723 + Fix various problems with glibc2.1. 20724 + Fix loop optimization bug exposed by rs6000/ppc port. 20725 + Fix to avoid potential code generation problems in jump.c. 20726 + Fix some undefined symbol problems in dwarf1 debug support. 20727 * g++/libstdc++ improvements and fixes 20728 + libstdc++ in the EGCS release has been updated and should be 20729 link compatible with libstdc++-2.8. 20730 + Various fixes in libio/libstdc++ to work better on GNU/Linux 20731 systems. 20732 + Fix problems with duplicate symbols on systems that do not 20733 support weak symbols. 20734 + Memory corruption bug and undefined symbols in bastring have 20735 been fixed. 20736 + Various exception handling fixes. 20737 + Fix compiler abort for very long thunk names. 20738 * g77 improvements and fixes 20739 + Fix compiler crash for omitted bound in Fortran CASE 20740 statement. 20741 + Add missing entries to g77 lang-options. 20742 + Fix problem with -fpedantic in the g77 compiler. 20743 + Fix "backspace" problem with g77 on alphas. 20744 + Fix x86 backend problem with Fortran literals and -fpic. 20745 + Fix some of the problems with negative subscripts for g77 on 20746 alphas. 20747 + Fixes for Fortran builds on cygwin32/mingw32. 20748 * platform specific improvements and fixes 20749 + Fix long double problems on x86 (exposed by glibc). 20750 + x86 ports define i386 again to keep imake happy. 20751 + Fix exception handling support on NetBSD ports. 20752 + Several changes to collect2 to fix many problems with AIX. 20753 + Define __ELF__ for GNU/Linux on rs6000. 20754 + Fix -mcall-linux problem on GNU/Linux on rs6000. 20755 + Fix stdarg/vararg problem for GNU/Linux on rs6000. 20756 + Allow autoconf to select a proper install problem on AIX 3.1. 20757 + m68k port support includes -mcpu32 option as well as cpu32 20758 multilibs. 20759 + Fix stdarg bug for irix6. 20760 + Allow EGCS to build on irix5 without the gnu assembler. 20761 + Fix problem with static linking on sco5. 20762 + Fix bootstrap on sco5 with native compiler. 20763 + Fix for abort building newlib on H8 target. 20764 + Fix fixincludes handling of math.h on SunOS. 20765 + Minor fix for Motorola 3300 m68k systems. 20766 20767 EGCS 1.0.3 is a minor update to the EGCS 1.0.2 compiler to fix a few 20768 problems reported by Red Hat for builds of Red Hat 5.1. 20769 * Generic bugfixes: 20770 + Fix a typo in the libio library which resulted in incorrect 20771 behavior of istream::get. 20772 + Fix the Fortran negative array index problem. 20773 + Fix a major problem with the ObjC runtime thread support 20774 exposed by glibc2. 20775 + Reduce memory consumption of the Haifa scheduler. 20776 * Target specific bugfixes: 20777 + Fix one x86 floating point code generation bug exposed by 20778 glibc2 builds. 20779 + Fix one x86 internal compiler error exposed by glibc2 builds. 20780 + Fix profiling bugs on the Alpha. 20781 + Fix ImageMagick & emacs 20.2 build problems on the Alpha. 20782 + Fix rs6000/ppc bug when converting values from integer types 20783 to floating point types. 20784 20785 The EGCS 1.0 releases include installation instructions in both HTML 20786 and plaintext forms (see the INSTALL directory in the toplevel 20787 directory of the distribution). However, we also keep the most up to 20788 date installation instructions and [2]build/test status on our web 20789 page. We will update those pages as new information becomes available. 20790 20791 And, we can't in good conscience fail to mention some [3]caveats to 20792 using EGCS. 20793 20794 Update: Big thanks to Stanford for providing a high speed link for 20795 downloading EGCS (go.cygnus.com)! 20796 20797 Download EGCS from ftp.cygnus.com (USA California) or go.cygnus.com 20798 (USA California -- High speed link provided by Stanford). 20799 20800 The EGCS 1.0 release is also available many mirror sites. 20801 [4]Goto mirror list to find a closer site 20802 20803 We'd like to thank the numerous people that have contributed new 20804 features, test results, bugfixes, etc. Unfortunately, they're far too 20805 numerous to mention by name. 20806 20807 20808 For questions related to the use of GCC, please consult these web 20809 pages and the [5]GCC manuals. If that fails, the 20810 [6]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20811 web pages and the development of GCC are welcome on our developer 20812 list at [7]gcc (a] gcc.gnu.org. All of [8]our lists have public archives. 20813 20814 Copyright (C) [9]Free Software Foundation, Inc. Verbatim copying and 20815 distribution of this entire article is permitted in any medium, 20816 provided this notice is preserved. 20817 20818 These pages are [10]maintained by the GCC team. Last modified 20819 2023-01-21. 20820 20821 References 20822 20823 1. http://gcc.gnu.org/egcs-1.0/features.html 20824 2. http://gcc.gnu.org/egcs-1.0/buildstat.html 20825 3. http://gcc.gnu.org/egcs-1.0/caveats.html 20826 4. http://gcc.gnu.org/mirrors.html 20827 5. https://gcc.gnu.org/onlinedocs/ 20828 6. mailto:gcc-help (a] gcc.gnu.org 20829 7. mailto:gcc (a] gcc.gnu.org 20830 8. https://gcc.gnu.org/lists.html 20831 9. https://www.fsf.org/ 20832 10. https://gcc.gnu.org/about.html 20833 ====================================================================== 20834 http://gcc.gnu.org/egcs-1.0/features.html 20835 20836 EGCS 1.0 features 20837 20838 * Core compiler is based on the gcc2 development tree from Aug 2, 20839 1997, so we have most of the [1]features found in GCC 2.8. 20840 * Integrated GNU Fortran compiler based on g77-0.5.22-19970929. 20841 * Vast improvements in the C++ compiler; so many they have [2]page of 20842 their own! 20843 * Integrated C++ runtime libraries, including support for most major 20844 GNU/Linux systems! 20845 * New instruction scheduler from IBM Haifa which includes support for 20846 function wide instruction scheduling as well as superscalar 20847 scheduling. 20848 * Significantly improved alias analysis code. 20849 * Improved register allocation for two address machines. 20850 * Significant code generation improvements for Fortran code on 20851 Alphas. 20852 * Various optimizations from the g77 project as well as improved loop 20853 optimizations. 20854 * Dwarf2 debug format support for some targets. 20855 * egcs libstdc++ includes the SGI STL implementation without changes. 20856 * As a result of these and other changes, egcs libstc++ is not binary 20857 compatible with previous releases of libstdc++. 20858 * Various new ports -- UltraSPARC, Irix6.2 & Irix6.3 support, The SCO 20859 Openserver 5 family (5.0.{0,2,4} and Internet FastStart 1.0 and 20860 1.1), Support for RTEMS on several embedded targets, Support for 20861 arm-linux, Mitsubishi M32R, Hitachi H8/S, Matsushita MN102 and 20862 MN103, NEC V850, Sparclet, Solaris & GNU/Linux on PowerPCs, etc. 20863 * Integrated testsuites for gcc, g++, g77, libstdc++ and libio. 20864 * RS6000/PowerPC ports generate code which can run on all 20865 RS6000/PowerPC variants by default. 20866 * -mcpu= and -march= switches for the x86 port to allow better 20867 control over how the x86 port generates code. 20868 * Includes the template repository patch (aka repo patch); note the 20869 new template code makes repo obsolete for ELF systems using gnu-ld 20870 such as GNU/Linux. 20871 * Plus the usual assortment of bugfixes and improvements. 20872 20873 20874 For questions related to the use of GCC, please consult these web 20875 pages and the [3]GCC manuals. If that fails, the 20876 [4]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20877 web pages and the development of GCC are welcome on our developer 20878 list at [5]gcc (a] gcc.gnu.org. All of [6]our lists have public archives. 20879 20880 Copyright (C) [7]Free Software Foundation, Inc. Verbatim copying and 20881 distribution of this entire article is permitted in any medium, 20882 provided this notice is preserved. 20883 20884 These pages are [8]maintained by the GCC team. Last modified 20885 2022-10-26. 20886 20887 References 20888 20889 1. http://gcc.gnu.org/egcs-1.0/features-2.8.html 20890 2. http://gcc.gnu.org/egcs-1.0/c++features.html 20891 3. https://gcc.gnu.org/onlinedocs/ 20892 4. mailto:gcc-help (a] gcc.gnu.org 20893 5. mailto:gcc (a] gcc.gnu.org 20894 6. https://gcc.gnu.org/lists.html 20895 7. https://www.fsf.org/ 20896 8. https://gcc.gnu.org/about.html 20897 ====================================================================== 20898 http://gcc.gnu.org/egcs-1.0/caveats.html 20899 20900 EGCS 1.0 Caveats 20901 20902 * EGCS has an integrated libstdc++, but does not have an integrated 20903 libg++. Furthermore old libg++ releases will not work with egc; HJ 20904 Lu has made a libg++-2.8.1.2 available which may work with EGCS. 20905 Note most C++ programs only need libstdc++. 20906 * Note that using -pedantic or -Wreturn-type can cause an explosion 20907 in the amount of memory needed for template-heavy C++ code, such as 20908 code that uses STL. Also note that -Wall includes -Wreturn-type, so 20909 if you use -Wall you will need to specify -Wno-return-type to turn 20910 it off. 20911 * Exception handling may not work with shared libraries, particularly 20912 on alphas, hppas, and mips based platforms. Exception handling is 20913 known to work on x86-linux platforms with shared libraries. 20914 * Some versions of the Linux kernel have bugs which prevent them from 20915 being compiled or from running when compiled by EGCS. See the FAQ 20916 (as shipped with EGCS 1.0) for additional information. 20917 * In general, EGCS is more rigorous about rejecting invalid C++ code 20918 or deprecated C++ constructs than G++ 2.7. As a result it may be 20919 necessary to fix C++ code before it will compile with EGCS. 20920 * G++ is also aggressively tracking the C++ standard; as a result 20921 code which was previously valid (and thus accepted by other 20922 compilers and older versions of G++) may no longer be accepted. 20923 * EGCS 1.0 may not work with Red Hat Linux 5.0 on all targets. EGCS 20924 1.0.x and later releases should work with Red Hat Linux 5.0. 20925 20926 20927 For questions related to the use of GCC, please consult these web 20928 pages and the [1]GCC manuals. If that fails, the 20929 [2]gcc-help (a] gcc.gnu.org mailing list might help. Comments on these 20930 web pages and the development of GCC are welcome on our developer 20931 list at [3]gcc (a] gcc.gnu.org. All of [4]our lists have public archives. 20932 20933 Copyright (C) [5]Free Software Foundation, Inc. Verbatim copying and 20934 distribution of this entire article is permitted in any medium, 20935 provided this notice is preserved. 20936 20937 These pages are [6]maintained by the GCC team. Last modified 20938 2022-10-26. 20939 20940 References 20941 20942 1. https://gcc.gnu.org/onlinedocs/ 20943 2. mailto:gcc-help (a] gcc.gnu.org 20944 3. mailto:gcc (a] gcc.gnu.org 20945 4. https://gcc.gnu.org/lists.html 20946 5. https://www.fsf.org/ 20947 6. https://gcc.gnu.org/about.html 20948 ====================================================================== 20949
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