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Copies published by the Free Software Foundation raise 21 funds for GNU development. --> 22 <!-- Created by GNU Texinfo 6.4, http://www.gnu.org/software/texinfo/ --> 23 <head> 24 <title>Installing GCC</title> 25 26 <meta name="description" content="Installing GCC"> 27 <meta name="keywords" content="Installing GCC"> 28 <meta name="resource-type" content="document"> 29 <meta name="distribution" content="global"> 30 <meta name="Generator" content="makeinfo"> 31 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 32 <style type="text/css"> 33 <!-- 34 a.summary-letter {text-decoration: none} 35 blockquote.indentedblock {margin-right: 0em} 36 blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} 37 blockquote.smallquotation {font-size: smaller} 38 div.display {margin-left: 3.2em} 39 div.example {margin-left: 3.2em} 40 div.lisp {margin-left: 3.2em} 41 div.smalldisplay {margin-left: 3.2em} 42 div.smallexample {margin-left: 3.2em} 43 div.smalllisp {margin-left: 3.2em} 44 kbd {font-style: oblique} 45 pre.display {font-family: inherit} 46 pre.format {font-family: inherit} 47 pre.menu-comment {font-family: serif} 48 pre.menu-preformatted {font-family: serif} 49 pre.smalldisplay {font-family: inherit; font-size: smaller} 50 pre.smallexample {font-size: smaller} 51 pre.smallformat {font-family: inherit; font-size: smaller} 52 pre.smalllisp {font-size: smaller} 53 span.nolinebreak {white-space: nowrap} 54 span.roman {font-family: initial; font-weight: normal} 55 span.sansserif {font-family: sans-serif; font-weight: normal} 56 ul.no-bullet {list-style: none} 57 --> 58 </style> 59 60 61 </head> 62 63 <body lang="en"> 64 <h1 class="settitle" align="center">Installing GCC</h1> 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 <a name="index-Configuration"></a> 85 <a name="index-Installing-GCC_003a-Configuration"></a> 86 87 <p>Like most GNU software, GCC must be configured before it can be built. 88 This document describes the recommended configuration procedure 89 for both native and cross targets. 90 </p> 91 <p>We use <var>srcdir</var> to refer to the toplevel source directory for 92 GCC; we use <var>objdir</var> to refer to the toplevel build/object directory. 93 </p> 94 <p>If you obtained the sources via SVN, <var>srcdir</var> must refer to the top 95 <samp>gcc</samp> directory, the one where the <samp>MAINTAINERS</samp> file can be 96 found, and not its <samp>gcc</samp> subdirectory, otherwise the build will fail. 97 </p> 98 <p>If either <var>srcdir</var> or <var>objdir</var> is located on an automounted NFS 99 file system, the shell’s built-in <code>pwd</code> command will return 100 temporary pathnames. Using these can lead to various sorts of build 101 problems. To avoid this issue, set the <code>PWDCMD</code> environment 102 variable to an automounter-aware <code>pwd</code> command, e.g., 103 <code>pawd</code> or ‘<samp>amq -w</samp>’, during the configuration and build 104 phases. 105 </p> 106 <p>First, we <strong>highly</strong> recommend that GCC be built into a 107 separate directory from the sources which does <strong>not</strong> reside 108 within the source tree. This is how we generally build GCC; building 109 where <var>srcdir</var> == <var>objdir</var> should still work, but doesn’t 110 get extensive testing; building where <var>objdir</var> is a subdirectory 111 of <var>srcdir</var> is unsupported. 112 </p> 113 <p>If you have previously built GCC in the same directory for a 114 different target machine, do ‘<samp>make distclean</samp>’ to delete all files 115 that might be invalid. One of the files this deletes is <samp>Makefile</samp>; 116 if ‘<samp>make distclean</samp>’ complains that <samp>Makefile</samp> does not exist 117 or issues a message like “don’t know how to make distclean” it probably 118 means that the directory is already suitably clean. However, with the 119 recommended method of building in a separate <var>objdir</var>, you should 120 simply use a different <var>objdir</var> for each target. 121 </p> 122 <p>Second, when configuring a native system, either <code>cc</code> or 123 <code>gcc</code> must be in your path or you must set <code>CC</code> in 124 your environment before running configure. Otherwise the configuration 125 scripts may fail. 126 </p> 127 128 <p>To configure GCC: 129 </p> 130 <div class="smallexample"> 131 <pre class="smallexample">% mkdir <var>objdir</var> 132 % cd <var>objdir</var> 133 % <var>srcdir</var>/configure [<var>options</var>] [<var>target</var>] 134 </pre></div> 135 136 <a name="Distributor-options"></a> 137 <h3 class="heading">Distributor options</h3> 138 139 <p>If you will be distributing binary versions of GCC, with modifications 140 to the source code, you should use the options described in this 141 section to make clear that your version contains modifications. 142 </p> 143 <dl compact="compact"> 144 <dt><code>--with-pkgversion=<var>version</var></code></dt> 145 <dd><p>Specify a string that identifies your package. You may wish 146 to include a build number or build date. This version string will be 147 included in the output of <code>gcc --version</code>. This suffix does 148 not replace the default version string, only the ‘<samp>GCC</samp>’ part. 149 </p> 150 <p>The default value is ‘<samp>GCC</samp>’. 151 </p> 152 </dd> 153 <dt><code>--with-bugurl=<var>url</var></code></dt> 154 <dd><p>Specify the URL that users should visit if they wish to report a bug. 155 You are of course welcome to forward bugs reported to you to the FSF, 156 if you determine that they are not bugs in your modifications. 157 </p> 158 <p>The default value refers to the FSF’s GCC bug tracker. 159 </p> 160 </dd> 161 </dl> 162 163 <a name="Target-specification"></a> 164 <h3 class="heading">Target specification</h3> 165 <ul> 166 <li> GCC has code to correctly determine the correct value for <var>target</var> 167 for nearly all native systems. Therefore, we highly recommend you do 168 not provide a configure target when configuring a native compiler. 169 170 </li><li> <var>target</var> must be specified as <samp>--target=<var>target</var></samp> 171 when configuring a cross compiler; examples of valid targets would be 172 m68k-elf, sh-elf, etc. 173 174 </li><li> Specifying just <var>target</var> instead of <samp>--target=<var>target</var></samp> 175 implies that the host defaults to <var>target</var>. 176 </li></ul> 177 178 179 <a name="Options-specification"></a> 180 <h3 class="heading">Options specification</h3> 181 182 <p>Use <var>options</var> to override several configure time options for 183 GCC. A list of supported <var>options</var> follows; ‘<samp>configure 184 --help</samp>’ may list other options, but those not listed below may not 185 work and should not normally be used. 186 </p> 187 <p>Note that each <samp>--enable</samp> option has a corresponding 188 <samp>--disable</samp> option and that each <samp>--with</samp> option has a 189 corresponding <samp>--without</samp> option. 190 </p> 191 <dl compact="compact"> 192 <dt><code>--prefix=<var>dirname</var></code></dt> 193 <dd><p>Specify the toplevel installation 194 directory. This is the recommended way to install the tools into a directory 195 other than the default. The toplevel installation directory defaults to 196 <samp>/usr/local</samp>. 197 </p> 198 <p>We <strong>highly</strong> recommend against <var>dirname</var> being the same or a 199 subdirectory of <var>objdir</var> or vice versa. If specifying a directory 200 beneath a user’s home directory tree, some shells will not expand 201 <var>dirname</var> correctly if it contains the ‘<samp>~</samp>’ metacharacter; use 202 <code>$HOME</code> instead. 203 </p> 204 <p>The following standard <code>autoconf</code> options are supported. Normally you 205 should not need to use these options. 206 </p><dl compact="compact"> 207 <dt><code>--exec-prefix=<var>dirname</var></code></dt> 208 <dd><p>Specify the toplevel installation directory for architecture-dependent 209 files. The default is <samp><var>prefix</var></samp>. 210 </p> 211 </dd> 212 <dt><code>--bindir=<var>dirname</var></code></dt> 213 <dd><p>Specify the installation directory for the executables called by users 214 (such as <code>gcc</code> and <code>g++</code>). The default is 215 <samp><var>exec-prefix</var>/bin</samp>. 216 </p> 217 </dd> 218 <dt><code>--libdir=<var>dirname</var></code></dt> 219 <dd><p>Specify the installation directory for object code libraries and 220 internal data files of GCC. The default is <samp><var>exec-prefix</var>/lib</samp>. 221 </p> 222 </dd> 223 <dt><code>--libexecdir=<var>dirname</var></code></dt> 224 <dd><p>Specify the installation directory for internal executables of GCC. 225 The default is <samp><var>exec-prefix</var>/libexec</samp>. 226 </p> 227 </dd> 228 <dt><code>--with-slibdir=<var>dirname</var></code></dt> 229 <dd><p>Specify the installation directory for the shared libgcc library. The 230 default is <samp><var>libdir</var></samp>. 231 </p> 232 </dd> 233 <dt><code>--datarootdir=<var>dirname</var></code></dt> 234 <dd><p>Specify the root of the directory tree for read-only architecture-independent 235 data files referenced by GCC. The default is <samp><var>prefix</var>/share</samp>. 236 </p> 237 </dd> 238 <dt><code>--infodir=<var>dirname</var></code></dt> 239 <dd><p>Specify the installation directory for documentation in info format. 240 The default is <samp><var>datarootdir</var>/info</samp>. 241 </p> 242 </dd> 243 <dt><code>--datadir=<var>dirname</var></code></dt> 244 <dd><p>Specify the installation directory for some architecture-independent 245 data files referenced by GCC. The default is <samp><var>datarootdir</var></samp>. 246 </p> 247 </dd> 248 <dt><code>--docdir=<var>dirname</var></code></dt> 249 <dd><p>Specify the installation directory for documentation files (other 250 than Info) for GCC. The default is <samp><var>datarootdir</var>/doc</samp>. 251 </p> 252 </dd> 253 <dt><code>--htmldir=<var>dirname</var></code></dt> 254 <dd><p>Specify the installation directory for HTML documentation files. 255 The default is <samp><var>docdir</var></samp>. 256 </p> 257 </dd> 258 <dt><code>--pdfdir=<var>dirname</var></code></dt> 259 <dd><p>Specify the installation directory for PDF documentation files. 260 The default is <samp><var>docdir</var></samp>. 261 </p> 262 </dd> 263 <dt><code>--mandir=<var>dirname</var></code></dt> 264 <dd><p>Specify the installation directory for manual pages. The default is 265 <samp><var>datarootdir</var>/man</samp>. (Note that the manual pages are only extracts 266 from the full GCC manuals, which are provided in Texinfo format. The manpages 267 are derived by an automatic conversion process from parts of the full 268 manual.) 269 </p> 270 </dd> 271 <dt><code>--with-gxx-include-dir=<var>dirname</var></code></dt> 272 <dd><p>Specify 273 the installation directory for G++ header files. The default depends 274 on other configuration options, and differs between cross and native 275 configurations. 276 </p> 277 </dd> 278 <dt><code>--with-specs=<var>specs</var></code></dt> 279 <dd><p>Specify additional command line driver SPECS. 280 This can be useful if you need to turn on a non-standard feature by 281 default without modifying the compiler’s source code, for instance 282 <samp>--with-specs=%{!fcommon:%{!fno-common:-fno-common}}</samp>. 283 See “Spec Files” in the main manual 284 </p> 285 </dd> 286 </dl> 287 288 </dd> 289 <dt><code>--program-prefix=<var>prefix</var></code></dt> 290 <dd><p>GCC supports some transformations of the names of its programs when 291 installing them. This option prepends <var>prefix</var> to the names of 292 programs to install in <var>bindir</var> (see above). For example, specifying 293 <samp>--program-prefix=foo-</samp> would result in ‘<samp>gcc</samp>’ 294 being installed as <samp>/usr/local/bin/foo-gcc</samp>. 295 </p> 296 </dd> 297 <dt><code>--program-suffix=<var>suffix</var></code></dt> 298 <dd><p>Appends <var>suffix</var> to the names of programs to install in <var>bindir</var> 299 (see above). For example, specifying <samp>--program-suffix=-3.1</samp> 300 would result in ‘<samp>gcc</samp>’ being installed as 301 <samp>/usr/local/bin/gcc-3.1</samp>. 302 </p> 303 </dd> 304 <dt><code>--program-transform-name=<var>pattern</var></code></dt> 305 <dd><p>Applies the ‘<samp>sed</samp>’ script <var>pattern</var> to be applied to the names 306 of programs to install in <var>bindir</var> (see above). <var>pattern</var> has to 307 consist of one or more basic ‘<samp>sed</samp>’ editing commands, separated by 308 semicolons. For example, if you want the ‘<samp>gcc</samp>’ program name to be 309 transformed to the installed program <samp>/usr/local/bin/myowngcc</samp> and 310 the ‘<samp>g++</samp>’ program name to be transformed to 311 <samp>/usr/local/bin/gspecial++</samp> without changing other program names, 312 you could use the pattern 313 <samp>--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'</samp> 314 to achieve this effect. 315 </p> 316 <p>All three options can be combined and used together, resulting in more 317 complex conversion patterns. As a basic rule, <var>prefix</var> (and 318 <var>suffix</var>) are prepended (appended) before further transformations 319 can happen with a special transformation script <var>pattern</var>. 320 </p> 321 <p>As currently implemented, this option only takes effect for native 322 builds; cross compiler binaries’ names are not transformed even when a 323 transformation is explicitly asked for by one of these options. 324 </p> 325 <p>For native builds, some of the installed programs are also installed 326 with the target alias in front of their name, as in 327 ‘<samp>i686-pc-linux-gnu-gcc</samp>’. All of the above transformations happen 328 before the target alias is prepended to the name—so, specifying 329 <samp>--program-prefix=foo-</samp> and <samp>program-suffix=-3.1</samp>, the 330 resulting binary would be installed as 331 <samp>/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1</samp>. 332 </p> 333 <p>As a last shortcoming, none of the installed Ada programs are 334 transformed yet, which will be fixed in some time. 335 </p> 336 </dd> 337 <dt><code>--with-local-prefix=<var>dirname</var></code></dt> 338 <dd><p>Specify the 339 installation directory for local include files. The default is 340 <samp>/usr/local</samp>. Specify this option if you want the compiler to 341 search directory <samp><var>dirname</var>/include</samp> for locally installed 342 header files <em>instead</em> of <samp>/usr/local/include</samp>. 343 </p> 344 <p>You should specify <samp>--with-local-prefix</samp> <strong>only</strong> if your 345 site has a different convention (not <samp>/usr/local</samp>) for where to put 346 site-specific files. 347 </p> 348 <p>The default value for <samp>--with-local-prefix</samp> is <samp>/usr/local</samp> 349 regardless of the value of <samp>--prefix</samp>. Specifying 350 <samp>--prefix</samp> has no effect on which directory GCC searches for 351 local header files. This may seem counterintuitive, but actually it is 352 logical. 353 </p> 354 <p>The purpose of <samp>--prefix</samp> is to specify where to <em>install 355 GCC</em>. The local header files in <samp>/usr/local/include</samp>—if you put 356 any in that directory—are not part of GCC. They are part of other 357 programs—perhaps many others. (GCC installs its own header files in 358 another directory which is based on the <samp>--prefix</samp> value.) 359 </p> 360 <p>Both the local-prefix include directory and the GCC-prefix include 361 directory are part of GCC’s “system include” directories. Although these 362 two directories are not fixed, they need to be searched in the proper 363 order for the correct processing of the include_next directive. The 364 local-prefix include directory is searched before the GCC-prefix 365 include directory. Another characteristic of system include directories 366 is that pedantic warnings are turned off for headers in these directories. 367 </p> 368 <p>Some autoconf macros add <samp>-I <var>directory</var></samp> options to the 369 compiler command line, to ensure that directories containing installed 370 packages’ headers are searched. When <var>directory</var> is one of GCC’s 371 system include directories, GCC will ignore the option so that system 372 directories continue to be processed in the correct order. This 373 may result in a search order different from what was specified but the 374 directory will still be searched. 375 </p> 376 <p>GCC automatically searches for ordinary libraries using 377 <code>GCC_EXEC_PREFIX</code>. Thus, when the same installation prefix is 378 used for both GCC and packages, GCC will automatically search for 379 both headers and libraries. This provides a configuration that is 380 easy to use. GCC behaves in a manner similar to that when it is 381 installed as a system compiler in <samp>/usr</samp>. 382 </p> 383 <p>Sites that need to install multiple versions of GCC may not want to 384 use the above simple configuration. It is possible to use the 385 <samp>--program-prefix</samp>, <samp>--program-suffix</samp> and 386 <samp>--program-transform-name</samp> options to install multiple versions 387 into a single directory, but it may be simpler to use different prefixes 388 and the <samp>--with-local-prefix</samp> option to specify the location of the 389 site-specific files for each version. It will then be necessary for 390 users to specify explicitly the location of local site libraries 391 (e.g., with <code>LIBRARY_PATH</code>). 392 </p> 393 <p>The same value can be used for both <samp>--with-local-prefix</samp> and 394 <samp>--prefix</samp> provided it is not <samp>/usr</samp>. This can be used 395 to avoid the default search of <samp>/usr/local/include</samp>. 396 </p> 397 <p><strong>Do not</strong> specify <samp>/usr</samp> as the <samp>--with-local-prefix</samp>! 398 The directory you use for <samp>--with-local-prefix</samp> <strong>must not</strong> 399 contain any of the system’s standard header files. If it did contain 400 them, certain programs would be miscompiled (including GNU Emacs, on 401 certain targets), because this would override and nullify the header 402 file corrections made by the <code>fixincludes</code> script. 403 </p> 404 <p>Indications are that people who use this option use it based on mistaken 405 ideas of what it is for. People use it as if it specified where to 406 install part of GCC. Perhaps they make this assumption because 407 installing GCC creates the directory. 408 </p> 409 </dd> 410 <dt><code>--with-native-system-header-dir=<var>dirname</var></code></dt> 411 <dd><p>Specifies that <var>dirname</var> is the directory that contains native system 412 header files, rather than <samp>/usr/include</samp>. This option is most useful 413 if you are creating a compiler that should be isolated from the system 414 as much as possible. It is most commonly used with the 415 <samp>--with-sysroot</samp> option and will cause GCC to search 416 <var>dirname</var> inside the system root specified by that option. 417 </p> 418 </dd> 419 <dt><code>--enable-shared[=<var>package</var>[,…]]</code></dt> 420 <dd><p>Build shared versions of libraries, if shared libraries are supported on 421 the target platform. Unlike GCC 2.95.x and earlier, shared libraries 422 are enabled by default on all platforms that support shared libraries. 423 </p> 424 <p>If a list of packages is given as an argument, build shared libraries 425 only for the listed packages. For other packages, only static libraries 426 will be built. Package names currently recognized in the GCC tree are 427 ‘<samp>libgcc</samp>’ (also known as ‘<samp>gcc</samp>’), ‘<samp>libstdc++</samp>’ (not 428 ‘<samp>libstdc++-v3</samp>’), ‘<samp>libffi</samp>’, ‘<samp>zlib</samp>’, ‘<samp>boehm-gc</samp>’, 429 ‘<samp>ada</samp>’, ‘<samp>libada</samp>’, ‘<samp>libjava</samp>’, ‘<samp>libgo</samp>’, and ‘<samp>libobjc</samp>’. 430 Note ‘<samp>libiberty</samp>’ does not support shared libraries at all. 431 </p> 432 <p>Use <samp>--disable-shared</samp> to build only static libraries. Note that 433 <samp>--disable-shared</samp> does not accept a list of package names as 434 argument, only <samp>--enable-shared</samp> does. 435 </p> 436 <p>Contrast with <samp>--enable-host-shared</samp>, which affects <em>host</em> 437 code. 438 </p> 439 </dd> 440 <dt><code>--enable-host-shared</code></dt> 441 <dd><p>Specify that the <em>host</em> code should be built into position-independent 442 machine code (with -fPIC), allowing it to be used within shared libraries, 443 but yielding a slightly slower compiler. 444 </p> 445 <p>This option is required when building the libgccjit.so library. 446 </p> 447 <p>Contrast with <samp>--enable-shared</samp>, which affects <em>target</em> 448 libraries. 449 </p> 450 </dd> 451 <dt><code><a name="with_002dgnu_002das"></a>--with-gnu-as</code></dt> 452 <dd><p>Specify that the compiler should assume that the 453 assembler it finds is the GNU assembler. However, this does not modify 454 the rules to find an assembler and will result in confusion if the 455 assembler found is not actually the GNU assembler. (Confusion may also 456 result if the compiler finds the GNU assembler but has not been 457 configured with <samp>--with-gnu-as</samp>.) If you have more than one 458 assembler installed on your system, you may want to use this option in 459 connection with <samp>--with-as=<var>pathname</var></samp> or 460 <samp>--with-build-time-tools=<var>pathname</var></samp>. 461 </p> 462 <p>The following systems are the only ones where it makes a difference 463 whether you use the GNU assembler. On any other system, 464 <samp>--with-gnu-as</samp> has no effect. 465 </p> 466 <ul> 467 <li> ‘<samp>hppa1.0-<var>any</var>-<var>any</var></samp>’ 468 </li><li> ‘<samp>hppa1.1-<var>any</var>-<var>any</var></samp>’ 469 </li><li> ‘<samp>sparc-sun-solaris2.<var>any</var></samp>’ 470 </li><li> ‘<samp>sparc64-<var>any</var>-solaris2.<var>any</var></samp>’ 471 </li></ul> 472 473 </dd> 474 <dt><code><a name="with_002das"></a>--with-as=<var>pathname</var></code></dt> 475 <dd><p>Specify that the compiler should use the assembler pointed to by 476 <var>pathname</var>, rather than the one found by the standard rules to find 477 an assembler, which are: 478 </p><ul> 479 <li> Unless GCC is being built with a cross compiler, check the 480 <samp><var>libexec</var>/gcc/<var>target</var>/<var>version</var></samp> directory. 481 <var>libexec</var> defaults to <samp><var>exec-prefix</var>/libexec</samp>; 482 <var>exec-prefix</var> defaults to <var>prefix</var>, which 483 defaults to <samp>/usr/local</samp> unless overridden by the 484 <samp>--prefix=<var>pathname</var></samp> switch described above. <var>target</var> 485 is the target system triple, such as ‘<samp>sparc-sun-solaris2.7</samp>’, and 486 <var>version</var> denotes the GCC version, such as 3.0. 487 488 </li><li> If the target system is the same that you are building on, check 489 operating system specific directories (e.g. <samp>/usr/ccs/bin</samp> on 490 Sun Solaris 2). 491 492 </li><li> Check in the <code>PATH</code> for a tool whose name is prefixed by the 493 target system triple. 494 495 </li><li> Check in the <code>PATH</code> for a tool whose name is not prefixed by the 496 target system triple, if the host and target system triple are 497 the same (in other words, we use a host tool if it can be used for 498 the target as well). 499 </li></ul> 500 501 <p>You may want to use <samp>--with-as</samp> if no assembler 502 is installed in the directories listed above, or if you have multiple 503 assemblers installed and want to choose one that is not found by the 504 above rules. 505 </p> 506 </dd> 507 <dt><code><a name="with_002dgnu_002dld"></a>--with-gnu-ld</code></dt> 508 <dd><p>Same as <a href="#with-gnu-as"><samp>--with-gnu-as</samp></a> 509 but for the linker. 510 </p> 511 </dd> 512 <dt><code>--with-ld=<var>pathname</var></code></dt> 513 <dd><p>Same as <a href="#with-as"><samp>--with-as</samp></a> 514 but for the linker. 515 </p> 516 </dd> 517 <dt><code>--with-stabs</code></dt> 518 <dd><p>Specify that stabs debugging 519 information should be used instead of whatever format the host normally 520 uses. Normally GCC uses the same debug format as the host system. 521 </p> 522 <p>On MIPS based systems and on Alphas, you must specify whether you want 523 GCC to create the normal ECOFF debugging format, or to use BSD-style 524 stabs passed through the ECOFF symbol table. The normal ECOFF debug 525 format cannot fully handle languages other than C. BSD stabs format can 526 handle other languages, but it only works with the GNU debugger GDB. 527 </p> 528 <p>Normally, GCC uses the ECOFF debugging format by default; if you 529 prefer BSD stabs, specify <samp>--with-stabs</samp> when you configure GCC. 530 </p> 531 <p>No matter which default you choose when you configure GCC, the user 532 can use the <samp>-gcoff</samp> and <samp>-gstabs+</samp> options to specify explicitly 533 the debug format for a particular compilation. 534 </p> 535 <p><samp>--with-stabs</samp> is meaningful on the ISC system on the 386, also, if 536 <samp>--with-gas</samp> is used. It selects use of stabs debugging 537 information embedded in COFF output. This kind of debugging information 538 supports C++ well; ordinary COFF debugging information does not. 539 </p> 540 <p><samp>--with-stabs</samp> is also meaningful on 386 systems running SVR4. It 541 selects use of stabs debugging information embedded in ELF output. The 542 C++ compiler currently (2.6.0) does not support the DWARF debugging 543 information normally used on 386 SVR4 platforms; stabs provide a 544 workable alternative. This requires gas and gdb, as the normal SVR4 545 tools can not generate or interpret stabs. 546 </p> 547 </dd> 548 <dt><code>--with-tls=<var>dialect</var></code></dt> 549 <dd><p>Specify the default TLS dialect, for systems were there is a choice. 550 For ARM targets, possible values for <var>dialect</var> are <code>gnu</code> or 551 <code>gnu2</code>, which select between the original GNU dialect and the GNU TLS 552 descriptor-based dialect. 553 </p> 554 </dd> 555 <dt><code>--enable-multiarch</code></dt> 556 <dd><p>Specify whether to enable or disable multiarch support. The default is 557 to check for glibc start files in a multiarch location, and enable it 558 if the files are found. The auto detection is enabled for native builds, 559 and for cross builds configured with <samp>--with-sysroot</samp>, and without 560 <samp>--with-native-system-header-dir</samp>. 561 More documentation about multiarch can be found at 562 <a href="https://wiki.debian.org/Multiarch">https://wiki.debian.org/Multiarch</a>. 563 </p> 564 </dd> 565 <dt><code>--enable-sjlj-exceptions</code></dt> 566 <dd><p>Force use of the <code>setjmp</code>/<code>longjmp</code>-based scheme for exceptions. 567 ‘<samp>configure</samp>’ ordinarily picks the correct value based on the platform. 568 Only use this option if you are sure you need a different setting. 569 </p> 570 </dd> 571 <dt><code>--enable-vtable-verify</code></dt> 572 <dd><p>Specify whether to enable or disable the vtable verification feature. 573 Enabling this feature causes libstdc++ to be built with its virtual calls 574 in verifiable mode. This means that, when linked with libvtv, every 575 virtual call in libstdc++ will verify the vtable pointer through which the 576 call will be made before actually making the call. If not linked with libvtv, 577 the verifier will call stub functions (in libstdc++ itself) and do nothing. 578 If vtable verification is disabled, then libstdc++ is not built with its 579 virtual calls in verifiable mode at all. However the libvtv library will 580 still be built (see <samp>--disable-libvtv</samp> to turn off building libvtv). 581 <samp>--disable-vtable-verify</samp> is the default. 582 </p> 583 </dd> 584 <dt><code>--disable-multilib</code></dt> 585 <dd><p>Specify that multiple target 586 libraries to support different target variants, calling 587 conventions, etc. should not be built. The default is to build a 588 predefined set of them. 589 </p> 590 <p>Some targets provide finer-grained control over which multilibs are built 591 (e.g., <samp>--disable-softfloat</samp>): 592 </p><dl compact="compact"> 593 <dt><code>arm-*-*</code></dt> 594 <dd><p>fpu, 26bit, underscore, interwork, biendian, nofmult. 595 </p> 596 </dd> 597 <dt><code>m68*-*-*</code></dt> 598 <dd><p>softfloat, m68881, m68000, m68020. 599 </p> 600 </dd> 601 <dt><code>mips*-*-*</code></dt> 602 <dd><p>single-float, biendian, softfloat. 603 </p> 604 </dd> 605 <dt><code>powerpc*-*-*, rs6000*-*-*</code></dt> 606 <dd><p>aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian, 607 sysv, aix. 608 </p> 609 </dd> 610 </dl> 611 612 </dd> 613 <dt><code>--with-multilib-list=<var>list</var></code></dt> 614 <dt><code>--without-multilib-list</code></dt> 615 <dd><p>Specify what multilibs to build. 616 Currently only implemented for arm*-*-*, sh*-*-* and x86-64-*-linux*. 617 </p> 618 <dl compact="compact"> 619 <dt><code>arm*-*-*</code></dt> 620 <dd><p><var>list</var> is either <code>default</code> or <code>aprofile</code>. Specifying 621 <code>default</code> is equivalent to omitting this option while specifying 622 <code>aprofile</code> builds multilibs for each combination of ISA (<code>-marm</code> or 623 <code>-mthumb</code>), architecture (<code>-march=armv7-a</code>, <code>-march=armv7ve</code>, 624 or <code>-march=armv8-a</code>), FPU available (none, <code>-mfpu=vfpv3-d16</code>, 625 <code>-mfpu=neon</code>, <code>-mfpu=vfpv4-d16</code>, <code>-mfpu=neon-vfpv4</code> or 626 <code>-mfpu=neon-fp-armv8</code> depending on architecture) and floating-point ABI 627 (<code>-mfloat-abi=softfp</code> or <code>-mfloat-abi=hard</code>). 628 </p> 629 </dd> 630 <dt><code>sh*-*-*</code></dt> 631 <dd><p><var>list</var> is a comma separated list of CPU names. These must be of the 632 form <code>sh*</code> or <code>m*</code> (in which case they match the compiler option 633 for that processor). The list should not contain any endian options - 634 these are handled by <samp>--with-endian</samp>. 635 </p> 636 <p>If <var>list</var> is empty, then there will be no multilibs for extra 637 processors. The multilib for the secondary endian remains enabled. 638 </p> 639 <p>As a special case, if an entry in the list starts with a <code>!</code> 640 (exclamation point), then it is added to the list of excluded multilibs. 641 Entries of this sort should be compatible with ‘<samp>MULTILIB_EXCLUDES</samp>’ 642 (once the leading <code>!</code> has been stripped). 643 </p> 644 <p>If <samp>--with-multilib-list</samp> is not given, then a default set of 645 multilibs is selected based on the value of <samp>--target</samp>. This is 646 usually the complete set of libraries, but some targets imply a more 647 specialized subset. 648 </p> 649 <p>Example 1: to configure a compiler for SH4A only, but supporting both 650 endians, with little endian being the default: 651 </p><div class="smallexample"> 652 <pre class="smallexample">--with-cpu=sh4a --with-endian=little,big --with-multilib-list= 653 </pre></div> 654 655 <p>Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with 656 only little endian SH4AL: 657 </p><div class="smallexample"> 658 <pre class="smallexample">--with-cpu=sh4a --with-endian=little,big \ 659 --with-multilib-list=sh4al,!mb/m4al 660 </pre></div> 661 662 </dd> 663 <dt><code>x86-64-*-linux*</code></dt> 664 <dd><p><var>list</var> is a comma separated list of <code>m32</code>, <code>m64</code> and 665 <code>mx32</code> to enable 32-bit, 64-bit and x32 run-time libraries, 666 respectively. If <var>list</var> is empty, then there will be no multilibs 667 and only the default run-time library will be enabled. 668 </p> 669 <p>If <samp>--with-multilib-list</samp> is not given, then only 32-bit and 670 64-bit run-time libraries will be enabled. 671 </p></dd> 672 </dl> 673 674 </dd> 675 <dt><code>--with-endian=<var>endians</var></code></dt> 676 <dd><p>Specify what endians to use. 677 Currently only implemented for sh*-*-*. 678 </p> 679 <p><var>endians</var> may be one of the following: 680 </p><dl compact="compact"> 681 <dt><code>big</code></dt> 682 <dd><p>Use big endian exclusively. 683 </p></dd> 684 <dt><code>little</code></dt> 685 <dd><p>Use little endian exclusively. 686 </p></dd> 687 <dt><code>big,little</code></dt> 688 <dd><p>Use big endian by default. Provide a multilib for little endian. 689 </p></dd> 690 <dt><code>little,big</code></dt> 691 <dd><p>Use little endian by default. Provide a multilib for big endian. 692 </p></dd> 693 </dl> 694 695 </dd> 696 <dt><code>--enable-threads</code></dt> 697 <dd><p>Specify that the target 698 supports threads. This affects the Objective-C compiler and runtime 699 library, and exception handling for other languages like C++ and Java. 700 On some systems, this is the default. 701 </p> 702 <p>In general, the best (and, in many cases, the only known) threading 703 model available will be configured for use. Beware that on some 704 systems, GCC has not been taught what threading models are generally 705 available for the system. In this case, <samp>--enable-threads</samp> is an 706 alias for <samp>--enable-threads=single</samp>. 707 </p> 708 </dd> 709 <dt><code>--disable-threads</code></dt> 710 <dd><p>Specify that threading support should be disabled for the system. 711 This is an alias for <samp>--enable-threads=single</samp>. 712 </p> 713 </dd> 714 <dt><code>--enable-threads=<var>lib</var></code></dt> 715 <dd><p>Specify that 716 <var>lib</var> is the thread support library. This affects the Objective-C 717 compiler and runtime library, and exception handling for other languages 718 like C++ and Java. The possibilities for <var>lib</var> are: 719 </p> 720 <dl compact="compact"> 721 <dt><code>aix</code></dt> 722 <dd><p>AIX thread support. 723 </p></dd> 724 <dt><code>dce</code></dt> 725 <dd><p>DCE thread support. 726 </p></dd> 727 <dt><code>lynx</code></dt> 728 <dd><p>LynxOS thread support. 729 </p></dd> 730 <dt><code>mipssde</code></dt> 731 <dd><p>MIPS SDE thread support. 732 </p></dd> 733 <dt><code>no</code></dt> 734 <dd><p>This is an alias for ‘<samp>single</samp>’. 735 </p></dd> 736 <dt><code>posix</code></dt> 737 <dd><p>Generic POSIX/Unix98 thread support. 738 </p></dd> 739 <dt><code>rtems</code></dt> 740 <dd><p>RTEMS thread support. 741 </p></dd> 742 <dt><code>single</code></dt> 743 <dd><p>Disable thread support, should work for all platforms. 744 </p></dd> 745 <dt><code>tpf</code></dt> 746 <dd><p>TPF thread support. 747 </p></dd> 748 <dt><code>vxworks</code></dt> 749 <dd><p>VxWorks thread support. 750 </p></dd> 751 <dt><code>win32</code></dt> 752 <dd><p>Microsoft Win32 API thread support. 753 </p></dd> 754 </dl> 755 756 </dd> 757 <dt><code>--enable-tls</code></dt> 758 <dd><p>Specify that the target supports TLS (Thread Local Storage). Usually 759 configure can correctly determine if TLS is supported. In cases where 760 it guesses incorrectly, TLS can be explicitly enabled or disabled with 761 <samp>--enable-tls</samp> or <samp>--disable-tls</samp>. This can happen if 762 the assembler supports TLS but the C library does not, or if the 763 assumptions made by the configure test are incorrect. 764 </p> 765 </dd> 766 <dt><code>--disable-tls</code></dt> 767 <dd><p>Specify that the target does not support TLS. 768 This is an alias for <samp>--enable-tls=no</samp>. 769 </p> 770 </dd> 771 <dt><code>--with-cpu=<var>cpu</var></code></dt> 772 <dt><code>--with-cpu-32=<var>cpu</var></code></dt> 773 <dt><code>--with-cpu-64=<var>cpu</var></code></dt> 774 <dd><p>Specify which cpu variant the compiler should generate code for by default. 775 <var>cpu</var> will be used as the default value of the <samp>-mcpu=</samp> switch. 776 This option is only supported on some targets, including ARC, ARM, i386, M68k, 777 PowerPC, and SPARC. It is mandatory for ARC. The <samp>--with-cpu-32</samp> and 778 <samp>--with-cpu-64</samp> options specify separate default CPUs for 779 32-bit and 64-bit modes; these options are only supported for i386, 780 x86-64, PowerPC, and SPARC. 781 </p> 782 </dd> 783 <dt><code>--with-schedule=<var>cpu</var></code></dt> 784 <dt><code>--with-arch=<var>cpu</var></code></dt> 785 <dt><code>--with-arch-32=<var>cpu</var></code></dt> 786 <dt><code>--with-arch-64=<var>cpu</var></code></dt> 787 <dt><code>--with-tune=<var>cpu</var></code></dt> 788 <dt><code>--with-tune-32=<var>cpu</var></code></dt> 789 <dt><code>--with-tune-64=<var>cpu</var></code></dt> 790 <dt><code>--with-abi=<var>abi</var></code></dt> 791 <dt><code>--with-fpu=<var>type</var></code></dt> 792 <dt><code>--with-float=<var>type</var></code></dt> 793 <dd><p>These configure options provide default values for the <samp>-mschedule=</samp>, 794 <samp>-march=</samp>, <samp>-mtune=</samp>, <samp>-mabi=</samp>, and <samp>-mfpu=</samp> 795 options and for <samp>-mhard-float</samp> or <samp>-msoft-float</samp>. As with 796 <samp>--with-cpu</samp>, which switches will be accepted and acceptable values 797 of the arguments depend on the target. 798 </p> 799 </dd> 800 <dt><code>--with-mode=<var>mode</var></code></dt> 801 <dd><p>Specify if the compiler should default to <samp>-marm</samp> or <samp>-mthumb</samp>. 802 This option is only supported on ARM targets. 803 </p> 804 </dd> 805 <dt><code>--with-stack-offset=<var>num</var></code></dt> 806 <dd><p>This option sets the default for the -mstack-offset=<var>num</var> option, 807 and will thus generally also control the setting of this option for 808 libraries. This option is only supported on Epiphany targets. 809 </p> 810 </dd> 811 <dt><code>--with-fpmath=<var>isa</var></code></dt> 812 <dd><p>This options sets <samp>-mfpmath=sse</samp> by default and specifies the default 813 ISA for floating-point arithmetics. You can select either ‘<samp>sse</samp>’ which 814 enables <samp>-msse2</samp> or ‘<samp>avx</samp>’ which enables <samp>-mavx</samp> by default. 815 This option is only supported on i386 and x86-64 targets. 816 </p> 817 </dd> 818 <dt><code>--with-fp-32=<var>mode</var></code></dt> 819 <dd><p>On MIPS targets, set the default value for the <samp>-mfp</samp> option when using 820 the o32 ABI. The possibilities for <var>mode</var> are: 821 </p><dl compact="compact"> 822 <dt><code>32</code></dt> 823 <dd><p>Use the o32 FP32 ABI extension, as with the <samp>-mfp32</samp> command-line 824 option. 825 </p></dd> 826 <dt><code>xx</code></dt> 827 <dd><p>Use the o32 FPXX ABI extension, as with the <samp>-mfpxx</samp> command-line 828 option. 829 </p></dd> 830 <dt><code>64</code></dt> 831 <dd><p>Use the o32 FP64 ABI extension, as with the <samp>-mfp64</samp> command-line 832 option. 833 </p></dd> 834 </dl> 835 <p>In the absence of this configuration option the default is to use the o32 836 FP32 ABI extension. 837 </p> 838 </dd> 839 <dt><code>--with-odd-spreg-32</code></dt> 840 <dd><p>On MIPS targets, set the <samp>-modd-spreg</samp> option by default when using 841 the o32 ABI. 842 </p> 843 </dd> 844 <dt><code>--without-odd-spreg-32</code></dt> 845 <dd><p>On MIPS targets, set the <samp>-mno-odd-spreg</samp> option by default when using 846 the o32 ABI. This is normally used in conjunction with 847 <samp>--with-fp-32=64</samp> in order to target the o32 FP64A ABI extension. 848 </p> 849 </dd> 850 <dt><code>--with-nan=<var>encoding</var></code></dt> 851 <dd><p>On MIPS targets, set the default encoding convention to use for the 852 special not-a-number (NaN) IEEE 754 floating-point data. The 853 possibilities for <var>encoding</var> are: 854 </p><dl compact="compact"> 855 <dt><code>legacy</code></dt> 856 <dd><p>Use the legacy encoding, as with the <samp>-mnan=legacy</samp> command-line 857 option. 858 </p></dd> 859 <dt><code>2008</code></dt> 860 <dd><p>Use the 754-2008 encoding, as with the <samp>-mnan=2008</samp> command-line 861 option. 862 </p></dd> 863 </dl> 864 <p>To use this configuration option you must have an assembler version 865 installed that supports the <samp>-mnan=</samp> command-line option too. 866 In the absence of this configuration option the default convention is 867 the legacy encoding, as when neither of the <samp>-mnan=2008</samp> and 868 <samp>-mnan=legacy</samp> command-line options has been used. 869 </p> 870 </dd> 871 <dt><code>--with-divide=<var>type</var></code></dt> 872 <dd><p>Specify how the compiler should generate code for checking for 873 division by zero. This option is only supported on the MIPS target. 874 The possibilities for <var>type</var> are: 875 </p><dl compact="compact"> 876 <dt><code>traps</code></dt> 877 <dd><p>Division by zero checks use conditional traps (this is the default on 878 systems that support conditional traps). 879 </p></dd> 880 <dt><code>breaks</code></dt> 881 <dd><p>Division by zero checks use the break instruction. 882 </p></dd> 883 </dl> 884 885 886 </dd> 887 <dt><code>--with-llsc</code></dt> 888 <dd><p>On MIPS targets, make <samp>-mllsc</samp> the default when no 889 <samp>-mno-llsc</samp> option is passed. This is the default for 890 Linux-based targets, as the kernel will emulate them if the ISA does 891 not provide them. 892 </p> 893 </dd> 894 <dt><code>--without-llsc</code></dt> 895 <dd><p>On MIPS targets, make <samp>-mno-llsc</samp> the default when no 896 <samp>-mllsc</samp> option is passed. 897 </p> 898 </dd> 899 <dt><code>--with-synci</code></dt> 900 <dd><p>On MIPS targets, make <samp>-msynci</samp> the default when no 901 <samp>-mno-synci</samp> option is passed. 902 </p> 903 </dd> 904 <dt><code>--without-synci</code></dt> 905 <dd><p>On MIPS targets, make <samp>-mno-synci</samp> the default when no 906 <samp>-msynci</samp> option is passed. This is the default. 907 </p> 908 </dd> 909 <dt><code>--with-mips-plt</code></dt> 910 <dd><p>On MIPS targets, make use of copy relocations and PLTs. 911 These features are extensions to the traditional 912 SVR4-based MIPS ABIs and require support from GNU binutils 913 and the runtime C library. 914 </p> 915 </dd> 916 <dt><code>--enable-__cxa_atexit</code></dt> 917 <dd><p>Define if you want to use __cxa_atexit, rather than atexit, to 918 register C++ destructors for local statics and global objects. 919 This is essential for fully standards-compliant handling of 920 destructors, but requires __cxa_atexit in libc. This option is currently 921 only available on systems with GNU libc. When enabled, this will cause 922 <samp>-fuse-cxa-atexit</samp> to be passed by default. 923 </p> 924 </dd> 925 <dt><code>--enable-gnu-indirect-function</code></dt> 926 <dd><p>Define if you want to enable the <code>ifunc</code> attribute. This option is 927 currently only available on systems with GNU libc on certain targets. 928 </p> 929 </dd> 930 <dt><code>--enable-target-optspace</code></dt> 931 <dd><p>Specify that target 932 libraries should be optimized for code space instead of code speed. 933 This is the default for the m32r platform. 934 </p> 935 </dd> 936 <dt><code>--with-cpp-install-dir=<var>dirname</var></code></dt> 937 <dd><p>Specify that the user visible <code>cpp</code> program should be installed 938 in <samp><var>prefix</var>/<var>dirname</var>/cpp</samp>, in addition to <var>bindir</var>. 939 </p> 940 </dd> 941 <dt><code>--enable-comdat</code></dt> 942 <dd><p>Enable COMDAT group support. This is primarily used to override the 943 automatically detected value. 944 </p> 945 </dd> 946 <dt><code>--enable-initfini-array</code></dt> 947 <dd><p>Force the use of sections <code>.init_array</code> and <code>.fini_array</code> 948 (instead of <code>.init</code> and <code>.fini</code>) for constructors and 949 destructors. Option <samp>--disable-initfini-array</samp> has the 950 opposite effect. If neither option is specified, the configure script 951 will try to guess whether the <code>.init_array</code> and 952 <code>.fini_array</code> sections are supported and, if they are, use them. 953 </p> 954 </dd> 955 <dt><code>--enable-link-mutex</code></dt> 956 <dd><p>When building GCC, use a mutex to avoid linking the compilers for 957 multiple languages at the same time, to avoid thrashing on build 958 systems with limited free memory. The default is not to use such a mutex. 959 </p> 960 </dd> 961 <dt><code>--enable-maintainer-mode</code></dt> 962 <dd><p>The build rules that regenerate the Autoconf and Automake output files as 963 well as the GCC master message catalog <samp>gcc.pot</samp> are normally 964 disabled. This is because it can only be rebuilt if the complete source 965 tree is present. If you have changed the sources and want to rebuild the 966 catalog, configuring with <samp>--enable-maintainer-mode</samp> will enable 967 this. Note that you need a recent version of the <code>gettext</code> tools 968 to do so. 969 </p> 970 </dd> 971 <dt><code>--disable-bootstrap</code></dt> 972 <dd><p>For a native build, the default configuration is to perform 973 a 3-stage bootstrap of the compiler when ‘<samp>make</samp>’ is invoked, 974 testing that GCC can compile itself correctly. If you want to disable 975 this process, you can configure with <samp>--disable-bootstrap</samp>. 976 </p> 977 </dd> 978 <dt><code>--enable-bootstrap</code></dt> 979 <dd><p>In special cases, you may want to perform a 3-stage build 980 even if the target and host triplets are different. 981 This is possible when the host can run code compiled for 982 the target (e.g. host is i686-linux, target is i486-linux). 983 Starting from GCC 4.2, to do this you have to configure explicitly 984 with <samp>--enable-bootstrap</samp>. 985 </p> 986 </dd> 987 <dt><code>--enable-generated-files-in-srcdir</code></dt> 988 <dd><p>Neither the .c and .h files that are generated from Bison and flex nor the 989 info manuals and man pages that are built from the .texi files are present 990 in the SVN development tree. When building GCC from that development tree, 991 or from one of our snapshots, those generated files are placed in your 992 build directory, which allows for the source to be in a readonly 993 directory. 994 </p> 995 <p>If you configure with <samp>--enable-generated-files-in-srcdir</samp> then those 996 generated files will go into the source directory. This is mainly intended 997 for generating release or prerelease tarballs of the GCC sources, since it 998 is not a requirement that the users of source releases to have flex, Bison, 999 or makeinfo. 1000 </p> 1001 </dd> 1002 <dt><code>--enable-version-specific-runtime-libs</code></dt> 1003 <dd><p>Specify 1004 that runtime libraries should be installed in the compiler specific 1005 subdirectory (<samp><var>libdir</var>/gcc</samp>) rather than the usual places. In 1006 addition, ‘<samp>libstdc++</samp>’’s include files will be installed into 1007 <samp><var>libdir</var></samp> unless you overruled it by using 1008 <samp>--with-gxx-include-dir=<var>dirname</var></samp>. Using this option is 1009 particularly useful if you intend to use several versions of GCC in 1010 parallel. This is currently supported by ‘<samp>libgfortran</samp>’, 1011 ‘<samp>libjava</samp>’, ‘<samp>libstdc++</samp>’, and ‘<samp>libobjc</samp>’. 1012 </p> 1013 </dd> 1014 <dt><code><a name="WithAixSoname"></a>--with-aix-soname=‘<samp>aix</samp>’, ‘<samp>svr4</samp>’ or ‘<samp>both</samp>’</code></dt> 1015 <dd><p>Traditional AIX shared library versioning (versioned <code>Shared Object</code> 1016 files as members of unversioned <code>Archive Library</code> files named 1017 ‘<samp>lib.a</samp>’) causes numerous headaches for package managers. However, 1018 <code>Import Files</code> as members of <code>Archive Library</code> files allow for 1019 <strong>filename-based versioning</strong> of shared libraries as seen on Linux/SVR4, 1020 where this is called the "SONAME". But as they prevent static linking, 1021 <code>Import Files</code> may be used with <code>Runtime Linking</code> only, where the 1022 linker does search for ‘<samp>libNAME.so</samp>’ before ‘<samp>libNAME.a</samp>’ library 1023 filenames with the ‘<samp>-lNAME</samp>’ linker flag. 1024 </p> 1025 <a name="AixLdCommand"></a><p>For detailed information please refer to the AIX 1026 <a href="http://www-01.ibm.com/support/knowledgecenter/search/%22the%20ld%20command%2C%20also%20called%20the%20linkage%20editor%20or%20binder%22">ld 1027 Command</a> reference. 1028 </p> 1029 <p>As long as shared library creation is enabled, upon: 1030 </p><dl compact="compact"> 1031 <dt><code>--with-aix-soname=aix</code></dt> 1032 <dt><code>--with-aix-soname=both</code></dt> 1033 <dd><p>A (traditional AIX) <code>Shared Archive Library</code> file is created: 1034 </p><ul> 1035 <li> using the ‘<samp>libNAME.a</samp>’ filename scheme 1036 </li><li> with the <code>Shared Object</code> file as archive member named 1037 ‘<samp>libNAME.so.V</samp>’ (except for ‘<samp>libgcc_s</samp>’, where the <code>Shared 1038 Object</code> file is named ‘<samp>shr.o</samp>’ for backwards compatibility), which 1039 <ul class="no-bullet"> 1040 <li>- is used for runtime loading from inside the ‘<samp>libNAME.a</samp>’ file 1041 </li><li>- is used for dynamic loading via 1042 <code>dlopen("libNAME.a(libNAME.so.V)", RTLD_MEMBER)</code> 1043 </li><li>- is used for shared linking 1044 </li><li>- is used for static linking, so no separate <code>Static Archive 1045 Library</code> file is needed 1046 </li></ul> 1047 </li></ul> 1048 </dd> 1049 <dt><code>--with-aix-soname=both</code></dt> 1050 <dt><code>--with-aix-soname=svr4</code></dt> 1051 <dd><p>A (second) <code>Shared Archive Library</code> file is created: 1052 </p><ul> 1053 <li> using the ‘<samp>libNAME.so.V</samp>’ filename scheme 1054 </li><li> with the <code>Shared Object</code> file as archive member named 1055 ‘<samp>shr.o</samp>’, which 1056 <ul class="no-bullet"> 1057 <li>- is created with the <code>-G linker flag</code> 1058 </li><li>- has the <code>F_LOADONLY</code> flag set 1059 </li><li>- is used for runtime loading from inside the ‘<samp>libNAME.so.V</samp>’ file 1060 </li><li>- is used for dynamic loading via <code>dlopen("libNAME.so.V(shr.o)", 1061 RTLD_MEMBER)</code> 1062 </li></ul> 1063 </li><li> with the <code>Import File</code> as archive member named ‘<samp>shr.imp</samp>’, 1064 which 1065 <ul class="no-bullet"> 1066 <li>- refers to ‘<samp>libNAME.so.V(shr.o)</samp>’ as the "SONAME", to be recorded 1067 in the <code>Loader Section</code> of subsequent binaries 1068 </li><li>- indicates whether ‘<samp>libNAME.so.V(shr.o)</samp>’ is 32 or 64 bit 1069 </li><li>- lists all the public symbols exported by ‘<samp>lib.so.V(shr.o)</samp>’, 1070 eventually decorated with the <code>‘<samp>weak</samp>’ Keyword</code> 1071 </li><li>- is necessary for shared linking against ‘<samp>lib.so.V(shr.o)</samp>’ 1072 </li></ul> 1073 </li></ul> 1074 <p>A symbolic link using the ‘<samp>libNAME.so</samp>’ filename scheme is created: 1075 </p><ul> 1076 <li> pointing to the ‘<samp>libNAME.so.V</samp>’ <code>Shared Archive Library</code> file 1077 </li><li> to permit the <code>ld Command</code> to find ‘<samp>lib.so.V(shr.imp)</samp>’ via 1078 the ‘<samp>-lNAME</samp>’ argument (requires <code>Runtime Linking</code> to be enabled) 1079 </li><li> to permit dynamic loading of ‘<samp>lib.so.V(shr.o)</samp>’ without the need 1080 to specify the version number via <code>dlopen("libNAME.so(shr.o)", 1081 RTLD_MEMBER)</code> 1082 </li></ul> 1083 </dd> 1084 </dl> 1085 1086 <p>As long as static library creation is enabled, upon: 1087 </p><dl compact="compact"> 1088 <dt><code>--with-aix-soname=svr4</code></dt> 1089 <dd><p>A <code>Static Archive Library</code> is created: 1090 </p><ul> 1091 <li> using the ‘<samp>libNAME.a</samp>’ filename scheme 1092 </li><li> with all the <code>Static Object</code> files as archive members, which 1093 <ul class="no-bullet"> 1094 <li>- are used for static linking 1095 </li></ul> 1096 </li></ul> 1097 </dd> 1098 </dl> 1099 1100 <p>While the aix-soname=‘<samp>svr4</samp>’ option does not create <code>Shared Object</code> 1101 files as members of unversioned <code>Archive Library</code> files any more, package 1102 managers still are responsible to 1103 <a href="./specific.html#TransferAixShobj">transfer</a> <code>Shared Object</code> files 1104 found as member of a previously installed unversioned <code>Archive Library</code> 1105 file into the newly installed <code>Archive Library</code> file with the same 1106 filename. 1107 </p> 1108 <p><em>WARNING:</em> Creating <code>Shared Object</code> files with <code>Runtime Linking</code> 1109 enabled may bloat the TOC, eventually leading to <code>TOC overflow</code> errors, 1110 requiring the use of either the <samp>-Wl,-bbigtoc</samp> linker flag (seen to 1111 break with the <code>GDB</code> debugger) or some of the TOC-related compiler flags, 1112 see “RS/6000 and PowerPC Options” in the main manual. 1113 </p> 1114 <p><samp>--with-aix-soname</samp> is currently supported by ‘<samp>libgcc_s</samp>’ only, so 1115 this option is still experimental and not for normal use yet. 1116 </p> 1117 <p>Default is the traditional behavior <samp>--with-aix-soname=‘<samp>aix</samp>’</samp>. 1118 </p> 1119 </dd> 1120 <dt><code>--enable-languages=<var>lang1</var>,<var>lang2</var>,…</code></dt> 1121 <dd><p>Specify that only a particular subset of compilers and 1122 their runtime libraries should be built. For a list of valid values for 1123 <var>langN</var> you can issue the following command in the 1124 <samp>gcc</samp> directory of your GCC source tree:<br> 1125 </p><div class="smallexample"> 1126 <pre class="smallexample">grep ^language= */config-lang.in 1127 </pre></div> 1128 <p>Currently, you can use any of the following: 1129 <code>all</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>fortran</code>, 1130 <code>go</code>, <code>java</code>, <code>jit</code>, <code>lto</code>, <code>objc</code>, <code>obj-c++</code>. 1131 Building the Ada compiler has special requirements, see below. 1132 If you do not pass this flag, or specify the option <code>all</code>, then all 1133 default languages available in the <samp>gcc</samp> sub-tree will be configured. 1134 Ada, Go, Jit, and Objective-C++ are not default languages. LTO is not a 1135 default language, but is built by default because <samp>--enable-lto</samp> is 1136 enabled by default. The other languages are default languages. 1137 </p> 1138 </dd> 1139 <dt><code>--enable-stage1-languages=<var>lang1</var>,<var>lang2</var>,…</code></dt> 1140 <dd><p>Specify that a particular subset of compilers and their runtime 1141 libraries should be built with the system C compiler during stage 1 of 1142 the bootstrap process, rather than only in later stages with the 1143 bootstrapped C compiler. The list of valid values is the same as for 1144 <samp>--enable-languages</samp>, and the option <code>all</code> will select all 1145 of the languages enabled by <samp>--enable-languages</samp>. This option is 1146 primarily useful for GCC development; for instance, when a development 1147 version of the compiler cannot bootstrap due to compiler bugs, or when 1148 one is debugging front ends other than the C front end. When this 1149 option is used, one can then build the target libraries for the 1150 specified languages with the stage-1 compiler by using <code>make 1151 stage1-bubble all-target</code>, or run the testsuite on the stage-1 compiler 1152 for the specified languages using <code>make stage1-start check-gcc</code>. 1153 </p> 1154 </dd> 1155 <dt><code>--disable-libada</code></dt> 1156 <dd><p>Specify that the run-time libraries and tools used by GNAT should not 1157 be built. This can be useful for debugging, or for compatibility with 1158 previous Ada build procedures, when it was required to explicitly 1159 do a ‘<samp>make -C gcc gnatlib_and_tools</samp>’. 1160 </p> 1161 </dd> 1162 <dt><code>--disable-libsanitizer</code></dt> 1163 <dd><p>Specify that the run-time libraries for the various sanitizers should 1164 not be built. 1165 </p> 1166 </dd> 1167 <dt><code>--disable-libssp</code></dt> 1168 <dd><p>Specify that the run-time libraries for stack smashing protection 1169 should not be built. 1170 </p> 1171 </dd> 1172 <dt><code>--disable-libquadmath</code></dt> 1173 <dd><p>Specify that the GCC quad-precision math library should not be built. 1174 On some systems, the library is required to be linkable when building 1175 the Fortran front end, unless <samp>--disable-libquadmath-support</samp> 1176 is used. 1177 </p> 1178 </dd> 1179 <dt><code>--disable-libquadmath-support</code></dt> 1180 <dd><p>Specify that the Fortran front end and <code>libgfortran</code> do not add 1181 support for <code>libquadmath</code> on systems supporting it. 1182 </p> 1183 </dd> 1184 <dt><code>--disable-libgomp</code></dt> 1185 <dd><p>Specify that the GNU Offloading and Multi Processing Runtime Library 1186 should not be built. 1187 </p> 1188 </dd> 1189 <dt><code>--disable-libvtv</code></dt> 1190 <dd><p>Specify that the run-time libraries used by vtable verification 1191 should not be built. 1192 </p> 1193 </dd> 1194 <dt><code>--with-dwarf2</code></dt> 1195 <dd><p>Specify that the compiler should 1196 use DWARF 2 debugging information as the default. 1197 </p> 1198 </dd> 1199 <dt><code>--with-advance-toolchain=<var>at</var></code></dt> 1200 <dd><p>On 64-bit PowerPC Linux systems, configure the compiler to use the 1201 header files, library files, and the dynamic linker from the Advance 1202 Toolchain release <var>at</var> instead of the default versions that are 1203 provided by the Linux distribution. In general, this option is 1204 intended for the developers of GCC, and it is not intended for general 1205 use. 1206 </p> 1207 </dd> 1208 <dt><code>--enable-targets=all</code></dt> 1209 <dt><code>--enable-targets=<var>target_list</var></code></dt> 1210 <dd><p>Some GCC targets, e.g. powerpc64-linux, build bi-arch compilers. 1211 These are compilers that are able to generate either 64-bit or 32-bit 1212 code. Typically, the corresponding 32-bit target, e.g. 1213 powerpc-linux for powerpc64-linux, only generates 32-bit code. This 1214 option enables the 32-bit target to be a bi-arch compiler, which is 1215 useful when you want a bi-arch compiler that defaults to 32-bit, and 1216 you are building a bi-arch or multi-arch binutils in a combined tree. 1217 On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64), 1218 defaulted to o32. 1219 Currently, this option only affects sparc-linux, powerpc-linux, x86-linux, 1220 mips-linux and s390-linux. 1221 </p> 1222 </dd> 1223 <dt><code>--enable-default-pie</code></dt> 1224 <dd><p>Turn on <samp>-fPIE</samp> and <samp>-pie</samp> by default. 1225 </p> 1226 </dd> 1227 <dt><code>--enable-secureplt</code></dt> 1228 <dd><p>This option enables <samp>-msecure-plt</samp> by default for powerpc-linux. 1229 See “RS/6000 and PowerPC Options” in the main manual 1230 </p> 1231 </dd> 1232 <dt><code>--enable-default-ssp</code></dt> 1233 <dd><p>Turn on <samp>-fstack-protector-strong</samp> by default. 1234 </p> 1235 </dd> 1236 <dt><code>--enable-cld</code></dt> 1237 <dd><p>This option enables <samp>-mcld</samp> by default for 32-bit x86 targets. 1238 See “i386 and x86-64 Options” in the main manual 1239 </p> 1240 </dd> 1241 <dt><code>--enable-win32-registry</code></dt> 1242 <dt><code>--enable-win32-registry=<var>key</var></code></dt> 1243 <dt><code>--disable-win32-registry</code></dt> 1244 <dd><p>The <samp>--enable-win32-registry</samp> option enables Microsoft Windows-hosted GCC 1245 to look up installations paths in the registry using the following key: 1246 </p> 1247 <div class="smallexample"> 1248 <pre class="smallexample"><code>HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<var>key</var></code> 1249 </pre></div> 1250 1251 <p><var>key</var> defaults to GCC version number, and can be overridden by the 1252 <samp>--enable-win32-registry=<var>key</var></samp> option. Vendors and distributors 1253 who use custom installers are encouraged to provide a different key, 1254 perhaps one comprised of vendor name and GCC version number, to 1255 avoid conflict with existing installations. This feature is enabled 1256 by default, and can be disabled by <samp>--disable-win32-registry</samp> 1257 option. This option has no effect on the other hosts. 1258 </p> 1259 </dd> 1260 <dt><code>--nfp</code></dt> 1261 <dd><p>Specify that the machine does not have a floating point unit. This 1262 option only applies to ‘<samp>m68k-sun-sunos<var>n</var></samp>’. On any other 1263 system, <samp>--nfp</samp> has no effect. 1264 </p> 1265 </dd> 1266 <dt><code>--enable-werror</code></dt> 1267 <dt><code>--disable-werror</code></dt> 1268 <dt><code>--enable-werror=yes</code></dt> 1269 <dt><code>--enable-werror=no</code></dt> 1270 <dd><p>When you specify this option, it controls whether certain files in the 1271 compiler are built with <samp>-Werror</samp> in bootstrap stage2 and later. 1272 If you don’t specify it, <samp>-Werror</samp> is turned on for the main 1273 development trunk. However it defaults to off for release branches and 1274 final releases. The specific files which get <samp>-Werror</samp> are 1275 controlled by the Makefiles. 1276 </p> 1277 </dd> 1278 <dt><code>--enable-checking</code></dt> 1279 <dt><code>--enable-checking=<var>list</var></code></dt> 1280 <dd><p>When you specify this option, the compiler is built to perform internal 1281 consistency checks of the requested complexity. This does not change the 1282 generated code, but adds error checking within the compiler. This will 1283 slow down the compiler and may only work properly if you are building 1284 the compiler with GCC. This is ‘<samp>yes</samp>’ by default when building 1285 from SVN or snapshots, but ‘<samp>release</samp>’ for releases. The default 1286 for building the stage1 compiler is ‘<samp>yes</samp>’. More control 1287 over the checks may be had by specifying <var>list</var>. The categories of 1288 checks available are ‘<samp>yes</samp>’ (most common checks 1289 ‘<samp>assert,misc,tree,gc,rtlflag,runtime</samp>’), ‘<samp>no</samp>’ (no checks at 1290 all), ‘<samp>all</samp>’ (all but ‘<samp>valgrind</samp>’), ‘<samp>release</samp>’ (cheapest 1291 checks ‘<samp>assert,runtime</samp>’) or ‘<samp>none</samp>’ (same as ‘<samp>no</samp>’). 1292 Individual checks can be enabled with these flags ‘<samp>assert</samp>’, 1293 ‘<samp>df</samp>’, ‘<samp>fold</samp>’, ‘<samp>gc</samp>’, ‘<samp>gcac</samp>’ ‘<samp>misc</samp>’, ‘<samp>rtl</samp>’, 1294 ‘<samp>rtlflag</samp>’, ‘<samp>runtime</samp>’, ‘<samp>tree</samp>’, and ‘<samp>valgrind</samp>’. 1295 </p> 1296 <p>The ‘<samp>valgrind</samp>’ check requires the external <code>valgrind</code> 1297 simulator, available from <a href="http://valgrind.org/">http://valgrind.org/</a>. The 1298 ‘<samp>df</samp>’, ‘<samp>rtl</samp>’, ‘<samp>gcac</samp>’ and ‘<samp>valgrind</samp>’ checks are very expensive. 1299 To disable all checking, ‘<samp>--disable-checking</samp>’ or 1300 ‘<samp>--enable-checking=none</samp>’ must be explicitly requested. Disabling 1301 assertions will make the compiler and runtime slightly faster but 1302 increase the risk of undetected internal errors causing wrong code to be 1303 generated. 1304 </p> 1305 </dd> 1306 <dt><code>--disable-stage1-checking</code></dt> 1307 <dt><code>--enable-stage1-checking</code></dt> 1308 <dt><code>--enable-stage1-checking=<var>list</var></code></dt> 1309 <dd><p>If no <samp>--enable-checking</samp> option is specified the stage1 1310 compiler will be built with ‘<samp>yes</samp>’ checking enabled, otherwise 1311 the stage1 checking flags are the same as specified by 1312 <samp>--enable-checking</samp>. To build the stage1 compiler with 1313 different checking options use <samp>--enable-stage1-checking</samp>. 1314 The list of checking options is the same as for <samp>--enable-checking</samp>. 1315 If your system is too slow or too small to bootstrap a released compiler 1316 with checking for stage1 enabled, you can use ‘<samp>--disable-stage1-checking</samp>’ 1317 to disable checking for the stage1 compiler. 1318 </p> 1319 </dd> 1320 <dt><code>--enable-coverage</code></dt> 1321 <dt><code>--enable-coverage=<var>level</var></code></dt> 1322 <dd><p>With this option, the compiler is built to collect self coverage 1323 information, every time it is run. This is for internal development 1324 purposes, and only works when the compiler is being built with gcc. The 1325 <var>level</var> argument controls whether the compiler is built optimized or 1326 not, values are ‘<samp>opt</samp>’ and ‘<samp>noopt</samp>’. For coverage analysis you 1327 want to disable optimization, for performance analysis you want to 1328 enable optimization. When coverage is enabled, the default level is 1329 without optimization. 1330 </p> 1331 </dd> 1332 <dt><code>--enable-gather-detailed-mem-stats</code></dt> 1333 <dd><p>When this option is specified more detailed information on memory 1334 allocation is gathered. This information is printed when using 1335 <samp>-fmem-report</samp>. 1336 </p> 1337 </dd> 1338 <dt><code>--enable-valgrind-annotations</code></dt> 1339 <dd><p>Mark selected memory related operations in the compiler when run under 1340 valgrind to suppress false positives. 1341 </p> 1342 </dd> 1343 <dt><code>--enable-nls</code></dt> 1344 <dt><code>--disable-nls</code></dt> 1345 <dd><p>The <samp>--enable-nls</samp> option enables Native Language Support (NLS), 1346 which lets GCC output diagnostics in languages other than American 1347 English. Native Language Support is enabled by default if not doing a 1348 canadian cross build. The <samp>--disable-nls</samp> option disables NLS. 1349 </p> 1350 </dd> 1351 <dt><code>--with-included-gettext</code></dt> 1352 <dd><p>If NLS is enabled, the <samp>--with-included-gettext</samp> option causes the build 1353 procedure to prefer its copy of GNU <code>gettext</code>. 1354 </p> 1355 </dd> 1356 <dt><code>--with-catgets</code></dt> 1357 <dd><p>If NLS is enabled, and if the host lacks <code>gettext</code> but has the 1358 inferior <code>catgets</code> interface, the GCC build procedure normally 1359 ignores <code>catgets</code> and instead uses GCC’s copy of the GNU 1360 <code>gettext</code> library. The <samp>--with-catgets</samp> option causes the 1361 build procedure to use the host’s <code>catgets</code> in this situation. 1362 </p> 1363 </dd> 1364 <dt><code>--with-libiconv-prefix=<var>dir</var></code></dt> 1365 <dd><p>Search for libiconv header files in <samp><var>dir</var>/include</samp> and 1366 libiconv library files in <samp><var>dir</var>/lib</samp>. 1367 </p> 1368 </dd> 1369 <dt><code>--enable-obsolete</code></dt> 1370 <dd><p>Enable configuration for an obsoleted system. If you attempt to 1371 configure GCC for a system (build, host, or target) which has been 1372 obsoleted, and you do not specify this flag, configure will halt with an 1373 error message. 1374 </p> 1375 <p>All support for systems which have been obsoleted in one release of GCC 1376 is removed entirely in the next major release, unless someone steps 1377 forward to maintain the port. 1378 </p> 1379 </dd> 1380 <dt><code>--enable-decimal-float</code></dt> 1381 <dt><code>--enable-decimal-float=yes</code></dt> 1382 <dt><code>--enable-decimal-float=no</code></dt> 1383 <dt><code>--enable-decimal-float=bid</code></dt> 1384 <dt><code>--enable-decimal-float=dpd</code></dt> 1385 <dt><code>--disable-decimal-float</code></dt> 1386 <dd><p>Enable (or disable) support for the C decimal floating point extension 1387 that is in the IEEE 754-2008 standard. This is enabled by default only 1388 on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also 1389 support it, but require the user to specifically enable it. You can 1390 optionally control which decimal floating point format is used (either 1391 ‘<samp>bid</samp>’ or ‘<samp>dpd</samp>’). The ‘<samp>bid</samp>’ (binary integer decimal) 1392 format is default on i386 and x86_64 systems, and the ‘<samp>dpd</samp>’ 1393 (densely packed decimal) format is default on PowerPC systems. 1394 </p> 1395 </dd> 1396 <dt><code>--enable-fixed-point</code></dt> 1397 <dt><code>--disable-fixed-point</code></dt> 1398 <dd><p>Enable (or disable) support for C fixed-point arithmetic. 1399 This option is enabled by default for some targets (such as MIPS) which 1400 have hardware-support for fixed-point operations. On other targets, you 1401 may enable this option manually. 1402 </p> 1403 </dd> 1404 <dt><code>--with-long-double-128</code></dt> 1405 <dd><p>Specify if <code>long double</code> type should be 128-bit by default on selected 1406 GNU/Linux architectures. If using <code>--without-long-double-128</code>, 1407 <code>long double</code> will be by default 64-bit, the same as <code>double</code> type. 1408 When neither of these configure options are used, the default will be 1409 128-bit <code>long double</code> when built against GNU C Library 2.4 and later, 1410 64-bit <code>long double</code> otherwise. 1411 </p> 1412 </dd> 1413 <dt><code>--enable-fdpic</code></dt> 1414 <dd><p>On SH Linux systems, generate ELF FDPIC code. 1415 </p> 1416 </dd> 1417 <dt><code>--with-gmp=<var>pathname</var></code></dt> 1418 <dt><code>--with-gmp-include=<var>pathname</var></code></dt> 1419 <dt><code>--with-gmp-lib=<var>pathname</var></code></dt> 1420 <dt><code>--with-mpfr=<var>pathname</var></code></dt> 1421 <dt><code>--with-mpfr-include=<var>pathname</var></code></dt> 1422 <dt><code>--with-mpfr-lib=<var>pathname</var></code></dt> 1423 <dt><code>--with-mpc=<var>pathname</var></code></dt> 1424 <dt><code>--with-mpc-include=<var>pathname</var></code></dt> 1425 <dt><code>--with-mpc-lib=<var>pathname</var></code></dt> 1426 <dd><p>If you want to build GCC but do not have the GMP library, the MPFR 1427 library and/or the MPC library installed in a standard location and 1428 do not have their sources present in the GCC source tree then you 1429 can explicitly specify the directory where they are installed 1430 (‘<samp>--with-gmp=<var>gmpinstalldir</var></samp>’, 1431 ‘<samp>--with-mpfr=<var>mpfrinstalldir</var></samp>’, 1432 ‘<samp>--with-mpc=<var>mpcinstalldir</var></samp>’). The 1433 <samp>--with-gmp=<var>gmpinstalldir</var></samp> option is shorthand for 1434 <samp>--with-gmp-lib=<var>gmpinstalldir</var>/lib</samp> and 1435 <samp>--with-gmp-include=<var>gmpinstalldir</var>/include</samp>. Likewise the 1436 <samp>--with-mpfr=<var>mpfrinstalldir</var></samp> option is shorthand for 1437 <samp>--with-mpfr-lib=<var>mpfrinstalldir</var>/lib</samp> and 1438 <samp>--with-mpfr-include=<var>mpfrinstalldir</var>/include</samp>, also the 1439 <samp>--with-mpc=<var>mpcinstalldir</var></samp> option is shorthand for 1440 <samp>--with-mpc-lib=<var>mpcinstalldir</var>/lib</samp> and 1441 <samp>--with-mpc-include=<var>mpcinstalldir</var>/include</samp>. If these 1442 shorthand assumptions are not correct, you can use the explicit 1443 include and lib options directly. You might also need to ensure the 1444 shared libraries can be found by the dynamic linker when building and 1445 using GCC, for example by setting the runtime shared library path 1446 variable (<code>LD_LIBRARY_PATH</code> on GNU/Linux and Solaris systems). 1447 </p> 1448 <p>These flags are applicable to the host platform only. When building 1449 a cross compiler, they will not be used to configure target libraries. 1450 </p> 1451 </dd> 1452 <dt><code>--with-isl=<var>pathname</var></code></dt> 1453 <dt><code>--with-isl-include=<var>pathname</var></code></dt> 1454 <dt><code>--with-isl-lib=<var>pathname</var></code></dt> 1455 <dd><p>If you do not have the isl library installed in a standard location and you 1456 want to build GCC, you can explicitly specify the directory where it is 1457 installed (‘<samp>--with-isl=<var>islinstalldir</var></samp>’). The 1458 <samp>--with-isl=<var>islinstalldir</var></samp> option is shorthand for 1459 <samp>--with-isl-lib=<var>islinstalldir</var>/lib</samp> and 1460 <samp>--with-isl-include=<var>islinstalldir</var>/include</samp>. If this 1461 shorthand assumption is not correct, you can use the explicit 1462 include and lib options directly. 1463 </p> 1464 <p>These flags are applicable to the host platform only. When building 1465 a cross compiler, they will not be used to configure target libraries. 1466 </p> 1467 </dd> 1468 <dt><code>--with-stage1-ldflags=<var>flags</var></code></dt> 1469 <dd><p>This option may be used to set linker flags to be used when linking 1470 stage 1 of GCC. These are also used when linking GCC if configured with 1471 <samp>--disable-bootstrap</samp>. If <samp>--with-stage1-libs</samp> is not set to a 1472 value, then the default is ‘<samp>-static-libstdc++ -static-libgcc</samp>’, if 1473 supported. 1474 </p> 1475 </dd> 1476 <dt><code>--with-stage1-libs=<var>libs</var></code></dt> 1477 <dd><p>This option may be used to set libraries to be used when linking stage 1 1478 of GCC. These are also used when linking GCC if configured with 1479 <samp>--disable-bootstrap</samp>. 1480 </p> 1481 </dd> 1482 <dt><code>--with-boot-ldflags=<var>flags</var></code></dt> 1483 <dd><p>This option may be used to set linker flags to be used when linking 1484 stage 2 and later when bootstrapping GCC. If –with-boot-libs 1485 is not is set to a value, then the default is 1486 ‘<samp>-static-libstdc++ -static-libgcc</samp>’. 1487 </p> 1488 </dd> 1489 <dt><code>--with-boot-libs=<var>libs</var></code></dt> 1490 <dd><p>This option may be used to set libraries to be used when linking stage 2 1491 and later when bootstrapping GCC. 1492 </p> 1493 </dd> 1494 <dt><code>--with-debug-prefix-map=<var>map</var></code></dt> 1495 <dd><p>Convert source directory names using <samp>-fdebug-prefix-map</samp> when 1496 building runtime libraries. ‘<samp><var>map</var></samp>’ is a space-separated 1497 list of maps of the form ‘<samp><var>old</var>=<var>new</var></samp>’. 1498 </p> 1499 </dd> 1500 <dt><code>--enable-linker-build-id</code></dt> 1501 <dd><p>Tells GCC to pass <samp>--build-id</samp> option to the linker for all final 1502 links (links performed without the <samp>-r</samp> or <samp>--relocatable</samp> 1503 option), if the linker supports it. If you specify 1504 <samp>--enable-linker-build-id</samp>, but your linker does not 1505 support <samp>--build-id</samp> option, a warning is issued and the 1506 <samp>--enable-linker-build-id</samp> option is ignored. The default is off. 1507 </p> 1508 </dd> 1509 <dt><code>--with-linker-hash-style=<var>choice</var></code></dt> 1510 <dd><p>Tells GCC to pass <samp>--hash-style=<var>choice</var></samp> option to the 1511 linker for all final links. <var>choice</var> can be one of 1512 ‘<samp>sysv</samp>’, ‘<samp>gnu</samp>’, and ‘<samp>both</samp>’ where ‘<samp>sysv</samp>’ is the default. 1513 </p> 1514 </dd> 1515 <dt><code>--enable-gnu-unique-object</code></dt> 1516 <dt><code>--disable-gnu-unique-object</code></dt> 1517 <dd><p>Tells GCC to use the gnu_unique_object relocation for C++ template 1518 static data members and inline function local statics. Enabled by 1519 default for a toolchain with an assembler that accepts it and 1520 GLIBC 2.11 or above, otherwise disabled. 1521 </p> 1522 </dd> 1523 <dt><code>--with-diagnostics-color=<var>choice</var></code></dt> 1524 <dd><p>Tells GCC to use <var>choice</var> as the default for <samp>-fdiagnostics-color=</samp> 1525 option (if not used explicitly on the command line). <var>choice</var> 1526 can be one of ‘<samp>never</samp>’, ‘<samp>auto</samp>’, ‘<samp>always</samp>’, and ‘<samp>auto-if-env</samp>’ 1527 where ‘<samp>auto</samp>’ is the default. ‘<samp>auto-if-env</samp>’ means that 1528 <samp>-fdiagnostics-color=auto</samp> will be the default if <code>GCC_COLORS</code> 1529 is present and non-empty in the environment, and 1530 <samp>-fdiagnostics-color=never</samp> otherwise. 1531 </p> 1532 </dd> 1533 <dt><code>--enable-lto</code></dt> 1534 <dt><code>--disable-lto</code></dt> 1535 <dd><p>Enable support for link-time optimization (LTO). This is enabled by 1536 default, and may be disabled using <samp>--disable-lto</samp>. 1537 </p> 1538 </dd> 1539 <dt><code>--enable-linker-plugin-configure-flags=FLAGS</code></dt> 1540 <dt><code>--enable-linker-plugin-flags=FLAGS</code></dt> 1541 <dd><p>By default, linker plugins (such as the LTO plugin) are built for the 1542 host system architecture. For the case that the linker has a 1543 different (but run-time compatible) architecture, these flags can be 1544 specified to build plugins that are compatible to the linker. For 1545 example, if you are building GCC for a 64-bit x86_64 1546 (‘<samp>x86_64-unknown-linux-gnu</samp>’) host system, but have a 32-bit x86 1547 GNU/Linux (‘<samp>i686-pc-linux-gnu</samp>’) linker executable (which is 1548 executable on the former system), you can configure GCC as follows for 1549 getting compatible linker plugins: 1550 </p> 1551 <div class="smallexample"> 1552 <pre class="smallexample">% <var>srcdir</var>/configure \ 1553 --host=x86_64-unknown-linux-gnu \ 1554 --enable-linker-plugin-configure-flags=--host=i686-pc-linux-gnu \ 1555 --enable-linker-plugin-flags='CC=gcc\ -m32\ -Wl,-rpath,[...]/i686-pc-linux-gnu/lib' 1556 </pre></div> 1557 1558 </dd> 1559 <dt><code>--with-plugin-ld=<var>pathname</var></code></dt> 1560 <dd><p>Enable an alternate linker to be used at link-time optimization (LTO) 1561 link time when <samp>-fuse-linker-plugin</samp> is enabled. 1562 This linker should have plugin support such as gold starting with 1563 version 2.20 or GNU ld starting with version 2.21. 1564 See <samp>-fuse-linker-plugin</samp> for details. 1565 </p> 1566 </dd> 1567 <dt><code>--enable-canonical-system-headers</code></dt> 1568 <dt><code>--disable-canonical-system-headers</code></dt> 1569 <dd><p>Enable system header path canonicalization for <samp>libcpp</samp>. This can 1570 produce shorter header file paths in diagnostics and dependency output 1571 files, but these changed header paths may conflict with some compilation 1572 environments. Enabled by default, and may be disabled using 1573 <samp>--disable-canonical-system-headers</samp>. 1574 </p> 1575 </dd> 1576 <dt><code>--with-glibc-version=<var>major</var>.<var>minor</var></code></dt> 1577 <dd><p>Tell GCC that when the GNU C Library (glibc) is used on the target it 1578 will be version <var>major</var>.<var>minor</var> or later. Normally this can 1579 be detected from the C library’s header files, but this option may be 1580 needed when bootstrapping a cross toolchain without the header files 1581 available for building the initial bootstrap compiler. 1582 </p> 1583 <p>If GCC is configured with some multilibs that use glibc and some that 1584 do not, this option applies only to the multilibs that use glibc. 1585 However, such configurations may not work well as not all the relevant 1586 configuration in GCC is on a per-multilib basis. 1587 </p> 1588 </dd> 1589 <dt><code>--enable-as-accelerator-for=<var>target</var></code></dt> 1590 <dd><p>Build as offload target compiler. Specify offload host triple by <var>target</var>. 1591 </p> 1592 </dd> 1593 <dt><code>--enable-offload-targets=<var>target1</var>[=<var>path1</var>],…,<var>targetN</var>[=<var>pathN</var>]</code></dt> 1594 <dd><p>Enable offloading to targets <var>target1</var>, …, <var>targetN</var>. 1595 Offload compilers are expected to be already installed. Default search 1596 path for them is <samp><var>exec-prefix</var></samp>, but it can be changed by 1597 specifying paths <var>path1</var>, …, <var>pathN</var>. 1598 </p> 1599 <div class="smallexample"> 1600 <pre class="smallexample">% <var>srcdir</var>/configure \ 1601 --enable-offload-target=i686-unknown-linux-gnu=/path/to/i686/compiler,x86_64-pc-linux-gnu 1602 </pre></div> 1603 1604 <p>If ‘<samp>hsa</samp>’ is specified as one of the targets, the compiler will be 1605 built with support for HSA GPU accelerators. Because the same 1606 compiler will emit the accelerator code, no path should be specified. 1607 </p> 1608 </dd> 1609 <dt><code>--with-hsa-runtime=<var>pathname</var></code></dt> 1610 <dt><code>--with-hsa-runtime-include=<var>pathname</var></code></dt> 1611 <dt><code>--with-hsa-runtime-lib=<var>pathname</var></code></dt> 1612 <dd> 1613 <p>If you configure GCC with HSA offloading but do not have the HSA 1614 run-time library installed in a standard location then you can 1615 explicitly specify the directory where they are installed. The 1616 <samp>--with-hsa-runtime=<var>hsainstalldir</var></samp> option is a 1617 shorthand for 1618 <samp>--with-hsa-runtime-lib=<var>hsainstalldir</var>/lib</samp> and 1619 <samp>--with-hsa-runtime-include=<var>hsainstalldir</var>/include</samp>. 1620 </p> 1621 </dd> 1622 <dt><code>--with-hsa-kmt-lib=<var>pathname</var></code></dt> 1623 <dd> 1624 <p>If you configure GCC with HSA offloading but do not have the HSA 1625 KMT library installed in a standard location then you can 1626 explicitly specify the directory where it resides. 1627 </p></dd> 1628 </dl> 1629 1630 <a name="Cross_002dCompiler_002dSpecific-Options"></a> 1631 <h4 class="subheading">Cross-Compiler-Specific Options</h4> 1632 <p>The following options only apply to building cross compilers. 1633 </p> 1634 <dl compact="compact"> 1635 <dt><code>--with-sysroot</code></dt> 1636 <dt><code>--with-sysroot=<var>dir</var></code></dt> 1637 <dd><p>Tells GCC to consider <var>dir</var> as the root of a tree that contains 1638 (a subset of) the root filesystem of the target operating system. 1639 Target system headers, libraries and run-time object files will be 1640 searched for in there. More specifically, this acts as if 1641 <samp>--sysroot=<var>dir</var></samp> was added to the default options of the built 1642 compiler. The specified directory is not copied into the 1643 install tree, unlike the options <samp>--with-headers</samp> and 1644 <samp>--with-libs</samp> that this option obsoletes. The default value, 1645 in case <samp>--with-sysroot</samp> is not given an argument, is 1646 <samp>${gcc_tooldir}/sys-root</samp>. If the specified directory is a 1647 subdirectory of <samp>${exec_prefix}</samp>, then it will be found relative to 1648 the GCC binaries if the installation tree is moved. 1649 </p> 1650 <p>This option affects the system root for the compiler used to build 1651 target libraries (which runs on the build system) and the compiler newly 1652 installed with <code>make install</code>; it does not affect the compiler which is 1653 used to build GCC itself. 1654 </p> 1655 <p>If you specify the <samp>--with-native-system-header-dir=<var>dirname</var></samp> 1656 option then the compiler will search that directory within <var>dirname</var> for 1657 native system headers rather than the default <samp>/usr/include</samp>. 1658 </p> 1659 </dd> 1660 <dt><code>--with-build-sysroot</code></dt> 1661 <dt><code>--with-build-sysroot=<var>dir</var></code></dt> 1662 <dd><p>Tells GCC to consider <var>dir</var> as the system root (see 1663 <samp>--with-sysroot</samp>) while building target libraries, instead of 1664 the directory specified with <samp>--with-sysroot</samp>. This option is 1665 only useful when you are already using <samp>--with-sysroot</samp>. You 1666 can use <samp>--with-build-sysroot</samp> when you are configuring with 1667 <samp>--prefix</samp> set to a directory that is different from the one in 1668 which you are installing GCC and your target libraries. 1669 </p> 1670 <p>This option affects the system root for the compiler used to build 1671 target libraries (which runs on the build system); it does not affect 1672 the compiler which is used to build GCC itself. 1673 </p> 1674 <p>If you specify the <samp>--with-native-system-header-dir=<var>dirname</var></samp> 1675 option then the compiler will search that directory within <var>dirname</var> for 1676 native system headers rather than the default <samp>/usr/include</samp>. 1677 </p> 1678 </dd> 1679 <dt><code>--with-headers</code></dt> 1680 <dt><code>--with-headers=<var>dir</var></code></dt> 1681 <dd><p>Deprecated in favor of <samp>--with-sysroot</samp>. 1682 Specifies that target headers are available when building a cross compiler. 1683 The <var>dir</var> argument specifies a directory which has the target include 1684 files. These include files will be copied into the <samp>gcc</samp> install 1685 directory. <em>This option with the <var>dir</var> argument is required</em> when 1686 building a cross compiler, if <samp><var>prefix</var>/<var>target</var>/sys-include</samp> 1687 doesn’t pre-exist. If <samp><var>prefix</var>/<var>target</var>/sys-include</samp> does 1688 pre-exist, the <var>dir</var> argument may be omitted. <code>fixincludes</code> 1689 will be run on these files to make them compatible with GCC. 1690 </p> 1691 </dd> 1692 <dt><code>--without-headers</code></dt> 1693 <dd><p>Tells GCC not use any target headers from a libc when building a cross 1694 compiler. When crossing to GNU/Linux, you need the headers so GCC 1695 can build the exception handling for libgcc. 1696 </p> 1697 </dd> 1698 <dt><code>--with-libs</code></dt> 1699 <dt><code>--with-libs="<var>dir1</var> <var>dir2</var> … <var>dirN</var>"</code></dt> 1700 <dd><p>Deprecated in favor of <samp>--with-sysroot</samp>. 1701 Specifies a list of directories which contain the target runtime 1702 libraries. These libraries will be copied into the <samp>gcc</samp> install 1703 directory. If the directory list is omitted, this option has no 1704 effect. 1705 </p> 1706 </dd> 1707 <dt><code>--with-newlib</code></dt> 1708 <dd><p>Specifies that ‘<samp>newlib</samp>’ is 1709 being used as the target C library. This causes <code>__eprintf</code> to be 1710 omitted from <samp>libgcc.a</samp> on the assumption that it will be provided by 1711 ‘<samp>newlib</samp>’. 1712 </p> 1713 </dd> 1714 <dt><code>--with-avrlibc</code></dt> 1715 <dd><p>Specifies that ‘<samp>AVR-Libc</samp>’ is 1716 being used as the target C library. This causes float support 1717 functions like <code>__addsf3</code> to be omitted from <samp>libgcc.a</samp> on 1718 the assumption that it will be provided by <samp>libm.a</samp>. For more 1719 technical details, cf. <a href="http://gcc.gnu.org/PR54461">PR54461</a>. 1720 This option is only supported for the AVR target. It is not supported for 1721 RTEMS configurations, which currently use newlib. The option is 1722 supported since version 4.7.2 and is the default in 4.8.0 and newer. 1723 </p> 1724 </dd> 1725 <dt><code>--with-nds32-lib=<var>library</var></code></dt> 1726 <dd><p>Specifies that <var>library</var> setting is used for building <samp>libgcc.a</samp>. 1727 Currently, the valid <var>library</var> is ‘<samp>newlib</samp>’ or ‘<samp>mculib</samp>’. 1728 This option is only supported for the NDS32 target. 1729 </p> 1730 </dd> 1731 <dt><code>--with-build-time-tools=<var>dir</var></code></dt> 1732 <dd><p>Specifies where to find the set of target tools (assembler, linker, etc.) 1733 that will be used while building GCC itself. This option can be useful 1734 if the directory layouts are different between the system you are building 1735 GCC on, and the system where you will deploy it. 1736 </p> 1737 <p>For example, on an ‘<samp>ia64-hp-hpux</samp>’ system, you may have the GNU 1738 assembler and linker in <samp>/usr/bin</samp>, and the native tools in a 1739 different path, and build a toolchain that expects to find the 1740 native tools in <samp>/usr/bin</samp>. 1741 </p> 1742 <p>When you use this option, you should ensure that <var>dir</var> includes 1743 <code>ar</code>, <code>as</code>, <code>ld</code>, <code>nm</code>, 1744 <code>ranlib</code> and <code>strip</code> if necessary, and possibly 1745 <code>objdump</code>. Otherwise, GCC may use an inconsistent set of 1746 tools. 1747 </p></dd> 1748 </dl> 1749 1750 <a name="Overriding-configure-test-results"></a> 1751 <h4 class="subsubheading">Overriding <code>configure</code> test results</h4> 1752 1753 <p>Sometimes, it might be necessary to override the result of some 1754 <code>configure</code> test, for example in order to ease porting to a new 1755 system or work around a bug in a test. The toplevel <code>configure</code> 1756 script provides three variables for this: 1757 </p> 1758 <dl compact="compact"> 1759 <dt><code>build_configargs</code></dt> 1760 <dd><a name="index-build_005fconfigargs"></a> 1761 <p>The contents of this variable is passed to all build <code>configure</code> 1762 scripts. 1763 </p> 1764 </dd> 1765 <dt><code>host_configargs</code></dt> 1766 <dd><a name="index-host_005fconfigargs"></a> 1767 <p>The contents of this variable is passed to all host <code>configure</code> 1768 scripts. 1769 </p> 1770 </dd> 1771 <dt><code>target_configargs</code></dt> 1772 <dd><a name="index-target_005fconfigargs"></a> 1773 <p>The contents of this variable is passed to all target <code>configure</code> 1774 scripts. 1775 </p> 1776 </dd> 1777 </dl> 1778 1779 <p>In order to avoid shell and <code>make</code> quoting issues for complex 1780 overrides, you can pass a setting for <code>CONFIG_SITE</code> and set 1781 variables in the site file. 1782 </p> 1783 <a name="Java_002dSpecific-Options"></a> 1784 <h4 class="subheading">Java-Specific Options</h4> 1785 1786 <p>The following option applies to the build of the Java front end. 1787 </p> 1788 <dl compact="compact"> 1789 <dt><code>--disable-libgcj</code></dt> 1790 <dd><p>Specify that the run-time libraries 1791 used by GCJ should not be built. This is useful in case you intend 1792 to use GCJ with some other run-time, or you’re going to install it 1793 separately, or it just happens not to build on your particular 1794 machine. In general, if the Java front end is enabled, the GCJ 1795 libraries will be enabled too, unless they’re known to not work on 1796 the target platform. If GCJ is enabled but ‘<samp>libgcj</samp>’ isn’t built, you 1797 may need to port it; in this case, before modifying the top-level 1798 <samp>configure.ac</samp> so that ‘<samp>libgcj</samp>’ is enabled by default on this platform, 1799 you may use <samp>--enable-libgcj</samp> to override the default. 1800 </p> 1801 </dd> 1802 </dl> 1803 1804 <p>The following options apply to building ‘<samp>libgcj</samp>’. 1805 </p> 1806 <a name="General-Options"></a> 1807 <h4 class="subsubheading">General Options</h4> 1808 1809 <dl compact="compact"> 1810 <dt><code>--enable-java-maintainer-mode</code></dt> 1811 <dd><p>By default the ‘<samp>libjava</samp>’ build will not attempt to compile the 1812 <samp>.java</samp> source files to <samp>.class</samp>. Instead, it will use the 1813 <samp>.class</samp> files from the source tree. If you use this option you 1814 must have executables named <code>ecj1</code> and <code>gjavah</code> in your path 1815 for use by the build. You must use this option if you intend to 1816 modify any <samp>.java</samp> files in <samp>libjava</samp>. 1817 </p> 1818 </dd> 1819 <dt><code>--with-java-home=<var>dirname</var></code></dt> 1820 <dd><p>This ‘<samp>libjava</samp>’ option overrides the default value of the 1821 ‘<samp>java.home</samp>’ system property. It is also used to set 1822 ‘<samp>sun.boot.class.path</samp>’ to <samp><var>dirname</var>/lib/rt.jar</samp>. By 1823 default ‘<samp>java.home</samp>’ is set to <samp><var>prefix</var></samp> and 1824 ‘<samp>sun.boot.class.path</samp>’ to 1825 <samp><var>datadir</var>/java/libgcj-<var>version</var>.jar</samp>. 1826 </p> 1827 </dd> 1828 <dt><code>--with-ecj-jar=<var>filename</var></code></dt> 1829 <dd><p>This option can be used to specify the location of an external jar 1830 file containing the Eclipse Java compiler. A specially modified 1831 version of this compiler is used by <code>gcj</code> to parse 1832 <samp>.java</samp> source files. If this option is given, the 1833 ‘<samp>libjava</samp>’ build will create and install an <samp>ecj1</samp> executable 1834 which uses this jar file at runtime. 1835 </p> 1836 <p>If this option is not given, but an <samp>ecj.jar</samp> file is found in 1837 the topmost source tree at configure time, then the ‘<samp>libgcj</samp>’ 1838 build will create and install <samp>ecj1</samp>, and will also install the 1839 discovered <samp>ecj.jar</samp> into a suitable place in the install tree. 1840 </p> 1841 <p>If <samp>ecj1</samp> is not installed, then the user will have to supply one 1842 on his path in order for <code>gcj</code> to properly parse <samp>.java</samp> 1843 source files. A suitable jar is available from 1844 <a href="ftp://sourceware.org/pub/java/">ftp://sourceware.org/pub/java/</a>. 1845 </p> 1846 </dd> 1847 <dt><code>--disable-getenv-properties</code></dt> 1848 <dd><p>Don’t set system properties from <code>GCJ_PROPERTIES</code>. 1849 </p> 1850 </dd> 1851 <dt><code>--enable-hash-synchronization</code></dt> 1852 <dd><p>Use a global hash table for monitor locks. Ordinarily, 1853 ‘<samp>libgcj</samp>’’s ‘<samp>configure</samp>’ script automatically makes 1854 the correct choice for this option for your platform. Only use 1855 this if you know you need the library to be configured differently. 1856 </p> 1857 </dd> 1858 <dt><code>--enable-interpreter</code></dt> 1859 <dd><p>Enable the Java interpreter. The interpreter is automatically 1860 enabled by default on all platforms that support it. This option 1861 is really only useful if you want to disable the interpreter 1862 (using <samp>--disable-interpreter</samp>). 1863 </p> 1864 </dd> 1865 <dt><code>--disable-java-net</code></dt> 1866 <dd><p>Disable java.net. This disables the native part of java.net only, 1867 using non-functional stubs for native method implementations. 1868 </p> 1869 </dd> 1870 <dt><code>--disable-jvmpi</code></dt> 1871 <dd><p>Disable JVMPI support. 1872 </p> 1873 </dd> 1874 <dt><code>--disable-libgcj-bc</code></dt> 1875 <dd><p>Disable BC ABI compilation of certain parts of libgcj. By default, 1876 some portions of libgcj are compiled with <samp>-findirect-dispatch</samp> 1877 and <samp>-fno-indirect-classes</samp>, allowing them to be overridden at 1878 run-time. 1879 </p> 1880 <p>If <samp>--disable-libgcj-bc</samp> is specified, libgcj is built without 1881 these options. This allows the compile-time linker to resolve 1882 dependencies when statically linking to libgcj. However it makes it 1883 impossible to override the affected portions of libgcj at run-time. 1884 </p> 1885 </dd> 1886 <dt><code>--enable-reduced-reflection</code></dt> 1887 <dd><p>Build most of libgcj with <samp>-freduced-reflection</samp>. This reduces 1888 the size of libgcj at the expense of not being able to do accurate 1889 reflection on the classes it contains. This option is safe if you 1890 know that code using libgcj will never use reflection on the standard 1891 runtime classes in libgcj (including using serialization, RMI or CORBA). 1892 </p> 1893 </dd> 1894 <dt><code>--with-ecos</code></dt> 1895 <dd><p>Enable runtime eCos target support. 1896 </p> 1897 </dd> 1898 <dt><code>--without-libffi</code></dt> 1899 <dd><p>Don’t use ‘<samp>libffi</samp>’. This will disable the interpreter and JNI 1900 support as well, as these require ‘<samp>libffi</samp>’ to work. 1901 </p> 1902 </dd> 1903 <dt><code>--enable-libgcj-debug</code></dt> 1904 <dd><p>Enable runtime debugging code. 1905 </p> 1906 </dd> 1907 <dt><code>--enable-libgcj-multifile</code></dt> 1908 <dd><p>If specified, causes all <samp>.java</samp> source files to be 1909 compiled into <samp>.class</samp> files in one invocation of 1910 ‘<samp>gcj</samp>’. This can speed up build time, but is more 1911 resource-intensive. If this option is unspecified or 1912 disabled, ‘<samp>gcj</samp>’ is invoked once for each <samp>.java</samp> 1913 file to compile into a <samp>.class</samp> file. 1914 </p> 1915 </dd> 1916 <dt><code>--with-libiconv-prefix=DIR</code></dt> 1917 <dd><p>Search for libiconv in <samp>DIR/include</samp> and <samp>DIR/lib</samp>. 1918 </p> 1919 </dd> 1920 <dt><code>--with-system-zlib</code></dt> 1921 <dd><p>Use installed ‘<samp>zlib</samp>’ rather than that included with GCC. 1922 </p> 1923 </dd> 1924 <dt><code>--with-win32-nlsapi=ansi, unicows or unicode</code></dt> 1925 <dd><p>Indicates how MinGW ‘<samp>libgcj</samp>’ translates between UNICODE 1926 characters and the Win32 API. 1927 </p> 1928 </dd> 1929 <dt><code>--enable-java-home</code></dt> 1930 <dd><p>If enabled, this creates a JPackage compatible SDK environment during install. 1931 Note that if –enable-java-home is used, –with-arch-directory=ARCH must also 1932 be specified. 1933 </p> 1934 </dd> 1935 <dt><code>--with-arch-directory=ARCH</code></dt> 1936 <dd><p>Specifies the name to use for the <samp>jre/lib/ARCH</samp> directory in the SDK 1937 environment created when –enable-java-home is passed. Typical names for this 1938 directory include i386, amd64, ia64, etc. 1939 </p> 1940 </dd> 1941 <dt><code>--with-os-directory=DIR</code></dt> 1942 <dd><p>Specifies the OS directory for the SDK include directory. This is set to auto 1943 detect, and is typically ’linux’. 1944 </p> 1945 </dd> 1946 <dt><code>--with-origin-name=NAME</code></dt> 1947 <dd><p>Specifies the JPackage origin name. This defaults to the ’gcj’ in 1948 java-1.5.0-gcj. 1949 </p> 1950 </dd> 1951 <dt><code>--with-arch-suffix=SUFFIX</code></dt> 1952 <dd><p>Specifies the suffix for the sdk directory. Defaults to the empty string. 1953 Examples include ’.x86_64’ in ’java-1.5.0-gcj-1.5.0.0.x86_64’. 1954 </p> 1955 </dd> 1956 <dt><code>--with-jvm-root-dir=DIR</code></dt> 1957 <dd><p>Specifies where to install the SDK. Default is $(prefix)/lib/jvm. 1958 </p> 1959 </dd> 1960 <dt><code>--with-jvm-jar-dir=DIR</code></dt> 1961 <dd><p>Specifies where to install jars. Default is $(prefix)/lib/jvm-exports. 1962 </p> 1963 </dd> 1964 <dt><code>--with-python-dir=DIR</code></dt> 1965 <dd><p>Specifies where to install the Python modules used for aot-compile. DIR should 1966 not include the prefix used in installation. For example, if the Python modules 1967 are to be installed in /usr/lib/python2.5/site-packages, then 1968 –with-python-dir=/lib/python2.5/site-packages should be passed. If this is 1969 not specified, then the Python modules are installed in $(prefix)/share/python. 1970 </p> 1971 </dd> 1972 <dt><code>--enable-aot-compile-rpm</code></dt> 1973 <dd><p>Adds aot-compile-rpm to the list of installed scripts. 1974 </p> 1975 </dd> 1976 <dt><code>--enable-browser-plugin</code></dt> 1977 <dd><p>Build the gcjwebplugin web browser plugin. 1978 </p> 1979 </dd> 1980 <dt><code>--enable-static-libjava</code></dt> 1981 <dd><p>Build static libraries in libjava. The default is to only build shared 1982 libraries. 1983 </p> 1984 <dl compact="compact"> 1985 <dt><code>ansi</code></dt> 1986 <dd><p>Use the single-byte <code>char</code> and the Win32 A functions natively, 1987 translating to and from UNICODE when using these functions. If 1988 unspecified, this is the default. 1989 </p> 1990 </dd> 1991 <dt><code>unicows</code></dt> 1992 <dd><p>Use the <code>WCHAR</code> and Win32 W functions natively. Adds 1993 <code>-lunicows</code> to <samp>libgcj.spec</samp> to link with ‘<samp>libunicows</samp>’. 1994 <samp>unicows.dll</samp> needs to be deployed on Microsoft Windows 9X machines 1995 running built executables. <samp>libunicows.a</samp>, an open-source 1996 import library around Microsoft’s <code>unicows.dll</code>, is obtained from 1997 <a href="http://libunicows.sourceforge.net/">http://libunicows.sourceforge.net/</a>, which also gives details 1998 on getting <samp>unicows.dll</samp> from Microsoft. 1999 </p> 2000 </dd> 2001 <dt><code>unicode</code></dt> 2002 <dd><p>Use the <code>WCHAR</code> and Win32 W functions natively. Does <em>not</em> 2003 add <code>-lunicows</code> to <samp>libgcj.spec</samp>. The built executables will 2004 only run on Microsoft Windows NT and above. 2005 </p></dd> 2006 </dl> 2007 </dd> 2008 </dl> 2009 2010 <a name="AWT_002dSpecific-Options"></a> 2011 <h4 class="subsubheading">AWT-Specific Options</h4> 2012 2013 <dl compact="compact"> 2014 <dt><code>--with-x</code></dt> 2015 <dd><p>Use the X Window System. 2016 </p> 2017 </dd> 2018 <dt><code>--enable-java-awt=PEER(S)</code></dt> 2019 <dd><p>Specifies the AWT peer library or libraries to build alongside 2020 ‘<samp>libgcj</samp>’. If this option is unspecified or disabled, AWT 2021 will be non-functional. Current valid values are <samp>gtk</samp> and 2022 <samp>xlib</samp>. Multiple libraries should be separated by a 2023 comma (i.e. <samp>--enable-java-awt=gtk,xlib</samp>). 2024 </p> 2025 </dd> 2026 <dt><code>--enable-gtk-cairo</code></dt> 2027 <dd><p>Build the cairo Graphics2D implementation on GTK. 2028 </p> 2029 </dd> 2030 <dt><code>--enable-java-gc=TYPE</code></dt> 2031 <dd><p>Choose garbage collector. Defaults to <samp>boehm</samp> if unspecified. 2032 </p> 2033 </dd> 2034 <dt><code>--disable-gtktest</code></dt> 2035 <dd><p>Do not try to compile and run a test GTK+ program. 2036 </p> 2037 </dd> 2038 <dt><code>--disable-glibtest</code></dt> 2039 <dd><p>Do not try to compile and run a test GLIB program. 2040 </p> 2041 </dd> 2042 <dt><code>--with-libart-prefix=PFX</code></dt> 2043 <dd><p>Prefix where libart is installed (optional). 2044 </p> 2045 </dd> 2046 <dt><code>--with-libart-exec-prefix=PFX</code></dt> 2047 <dd><p>Exec prefix where libart is installed (optional). 2048 </p> 2049 </dd> 2050 <dt><code>--disable-libarttest</code></dt> 2051 <dd><p>Do not try to compile and run a test libart program. 2052 </p> 2053 </dd> 2054 </dl> 2055 2056 2057 <hr /> 2058 <p> 2059 <p><a href="./index.html">Return to the GCC Installation page</a> 2060 </p> 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 </body> 2073 </html> 2074
Indexes created Thu Jul 16 00:26:27 UTC 2026