1 /* Specific flags and argument handling of the C++ front end. 2 Copyright (C) 1996-2024 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 any later version. 10 11 GCC is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #include "config.h" 21 #include "system.h" 22 #include "coretypes.h" 23 #include "tm.h" 24 #include "opts.h" 25 26 /* This bit is set if we saw a `-xfoo' language specification. */ 27 #define LANGSPEC (1<<1) 28 /* This bit is set if they did `-lm' or `-lmath'. */ 29 #define MATHLIB (1<<2) 30 /* This bit is set if they did `-lc'. */ 31 #define WITHLIBC (1<<3) 32 /* Skip this option. */ 33 #define SKIPOPT (1<<4) 34 /* Add -lstdc++exp for experimental features that need library support. */ 35 #define EXPERIMENTAL (1<<5) 36 37 #ifndef MATH_LIBRARY 38 #define MATH_LIBRARY "m" 39 #endif 40 #ifndef MATH_LIBRARY_PROFILE 41 #define MATH_LIBRARY_PROFILE MATH_LIBRARY 42 #endif 43 44 #ifndef LIBSTDCXX 45 #define LIBSTDCXX "stdc++" 46 #endif 47 #ifndef LIBSTDCXX_PROFILE 48 #define LIBSTDCXX_PROFILE LIBSTDCXX 49 #endif 50 #ifndef LIBSTDCXX_STATIC 51 #define LIBSTDCXX_STATIC NULL 52 #endif 53 54 #ifndef LIBCXX 55 #define LIBCXX "c++" 56 #endif 57 #ifndef LIBCXX_PROFILE 58 #define LIBCXX_PROFILE LIBCXX 59 #endif 60 #ifndef LIBCXX_STATIC 61 #define LIBCXX_STATIC NULL 62 #endif 63 64 #ifndef LIBCXXABI 65 #define LIBCXXABI "c++abi" 66 #endif 67 #ifndef LIBCXXABI_PROFILE 68 #define LIBCXXABI_PROFILE LIBCXXABI 69 #endif 70 #ifndef LIBCXXABI_STATIC 71 #define LIBCXXABI_STATIC NULL 72 #endif 73 74 /* The values used here must match those of the stdlib_kind enumeration 75 in c.opt. */ 76 enum stdcxxlib_kind 77 { 78 USE_LIBSTDCXX = 1, 79 USE_LIBCXX = 2 80 }; 81 82 void 83 lang_specific_driver (struct cl_decoded_option **in_decoded_options, 84 unsigned int *in_decoded_options_count, 85 int *in_added_libraries) 86 { 87 unsigned int i, j; 88 89 /* If nonzero, the user gave us the `-p' or `-pg' flag. */ 90 int saw_profile_flag = 0; 91 92 /* What action to take for the c++ runtime library: 93 -1 means we should not link it in. 94 0 means we should link it if it is needed. 95 1 means it is needed and should be linked in. 96 2 means it is needed but should be linked statically. */ 97 int library = 0; 98 99 /* Which c++ runtime library to link. */ 100 stdcxxlib_kind which_library = USE_LIBSTDCXX; 101 102 /* The number of arguments being added to what's in argv, other than 103 libraries. We use this to track the number of times we've inserted 104 -xc++/-xnone. */ 105 int added = 0; 106 107 /* The new argument list will be contained in this. */ 108 struct cl_decoded_option *new_decoded_options; 109 110 /* Nonzero if we saw a `-xfoo' language specification on the 111 command line. Used to avoid adding our own -xc++ if the user 112 already gave a language for the file. */ 113 int saw_speclang = 0; 114 115 /* "-lm" or "-lmath" if it appears on the command line. */ 116 const struct cl_decoded_option *saw_math = NULL; 117 118 /* "-lrt" or eqivalent if it appears on the command line. */ 119 const struct cl_decoded_option *saw_time = NULL; 120 121 /* "-lc" if it appears on the command line. */ 122 const struct cl_decoded_option *saw_libc = NULL; 123 124 /* An array used to flag each argument that needs a bit set for 125 LANGSPEC, MATHLIB, or WITHLIBC. */ 126 int *args; 127 128 /* By default, we throw on the math library if we have one. */ 129 int need_math = (MATH_LIBRARY[0] != '\0'); 130 131 /* By default, we don't add -lstdc++exp. */ 132 bool need_experimental = false; 133 134 /* True if we saw -static. */ 135 int static_link = 0; 136 137 /* True if we should add -shared-libgcc to the command-line. */ 138 int shared_libgcc = 1; 139 140 /* The total number of arguments with the new stuff. */ 141 unsigned int argc; 142 143 /* The argument list. */ 144 struct cl_decoded_option *decoded_options; 145 146 /* The number of libraries added in. */ 147 int added_libraries; 148 149 /* The total number of arguments with the new stuff. */ 150 unsigned int num_args = 1; 151 152 argc = *in_decoded_options_count; 153 decoded_options = *in_decoded_options; 154 added_libraries = *in_added_libraries; 155 156 args = XCNEWVEC (int, argc); 157 158 for (i = 1; i < argc; i++) 159 { 160 const char *arg = decoded_options[i].arg; 161 if (decoded_options[i].errors & CL_ERR_MISSING_ARG) 162 continue; /* Avoid examining arguments of options missing them. */ 163 164 switch (decoded_options[i].opt_index) 165 { 166 case OPT_fcontracts: 167 need_experimental = true; 168 break; 169 170 case OPT_nostdlib__: 171 args[i] |= SKIPOPT; 172 /* FALLTHRU */ 173 case OPT_nostdlib: 174 case OPT_nodefaultlibs: 175 library = -1; 176 break; 177 178 case OPT_l: 179 if (strcmp (arg, MATH_LIBRARY) == 0) 180 { 181 args[i] |= MATHLIB; 182 need_math = 0; 183 } 184 else if (strcmp (arg, "c") == 0) 185 args[i] |= WITHLIBC; 186 else 187 /* Unrecognized libraries (e.g. -lfoo) may require libstdc++. */ 188 library = (library == 0) ? 1 : library; 189 break; 190 191 case OPT_pg: 192 case OPT_p: 193 saw_profile_flag++; 194 break; 195 196 case OPT_x: 197 if (library == 0 198 && (strcmp (arg, "c++") == 0 199 || strcmp (arg, "c++-cpp-output") == 0 200 || strcmp (arg, "objective-c++") == 0 201 || strcmp (arg, "objective-c++-cpp-output") == 0)) 202 library = 1; 203 204 saw_speclang = 1; 205 break; 206 207 case OPT_Xlinker: 208 case OPT_Wl_: 209 /* Arguments that go directly to the linker might be .o files, 210 or something, and so might cause libstdc++ to be needed. */ 211 if (library == 0) 212 library = 1; 213 break; 214 215 case OPT_c: 216 case OPT_r: 217 case OPT_S: 218 case OPT_E: 219 case OPT_M: 220 case OPT_MM: 221 case OPT_fsyntax_only: 222 /* Don't specify libraries if we won't link, since that would 223 cause a warning. */ 224 library = -1; 225 break; 226 227 case OPT_static: 228 static_link = 1; 229 break; 230 231 case OPT_static_libgcc: 232 shared_libgcc = 0; 233 break; 234 235 case OPT_static_libstdc__: 236 library = library >= 0 ? 2 : library; 237 #ifdef HAVE_LD_STATIC_DYNAMIC 238 /* Remove -static-libstdc++ from the command only if target supports 239 LD_STATIC_DYNAMIC. When not supported, it is left in so that a 240 back-end target can use outfile substitution. */ 241 args[i] |= SKIPOPT; 242 #endif 243 break; 244 245 case OPT_stdlib_: 246 which_library = (stdcxxlib_kind) decoded_options[i].value; 247 break; 248 249 case OPT_SPECIAL_input_file: 250 { 251 int len; 252 253 /* We don't do this anymore, since we don't get them with minus 254 signs on them. */ 255 if (arg[0] == '\0' || arg[1] == '\0') 256 continue; 257 258 if (saw_speclang) 259 { 260 saw_speclang = 0; 261 continue; 262 } 263 264 /* If the filename ends in .[chi], put options around it. 265 But not if a specified -x option is currently active. */ 266 len = strlen (arg); 267 if (len > 2 268 && (arg[len - 1] == 'c' 269 || arg[len - 1] == 'i' 270 || arg[len - 1] == 'h') 271 && arg[len - 2] == '.') 272 { 273 args[i] |= LANGSPEC; 274 added += 2; 275 } 276 277 /* If we don't know that this is a header file, we might 278 need to be linking in the libraries. */ 279 if (library == 0) 280 { 281 if ((len <= 2 || strcmp (arg + (len - 2), ".H") != 0) 282 && (len <= 2 || strcmp (arg + (len - 2), ".h") != 0) 283 && (len <= 4 || strcmp (arg + (len - 4), ".hpp") != 0) 284 && (len <= 3 || strcmp (arg + (len - 3), ".hp") != 0) 285 && (len <= 4 || strcmp (arg + (len - 4), ".hxx") != 0) 286 && (len <= 4 || strcmp (arg + (len - 4), ".h++") != 0) 287 && (len <= 4 || strcmp (arg + (len - 4), ".HPP") != 0) 288 && (len <= 4 || strcmp (arg + (len - 4), ".tcc") != 0) 289 && (len <= 3 || strcmp (arg + (len - 3), ".hh") != 0)) 290 library = 1; 291 } 292 } 293 break; 294 } 295 } 296 297 /* There's no point adding -shared-libgcc if we don't have a shared 298 libgcc. */ 299 #ifndef ENABLE_SHARED_LIBGCC 300 shared_libgcc = 0; 301 #endif 302 303 /* Add one for shared_libgcc or extra static library. */ 304 num_args = (argc + added + need_math + need_experimental 305 + (library > 0) * 4 + 1); 306 /* For libc++, on most platforms, the ABI library (usually called libc++abi) 307 is provided as a separate DSO, which we must also append. 308 However, a platform might have the ability to forward the ABI library 309 from libc++, or combine it in some other way; in that case, LIBCXXABI 310 should be set to NULL to signal that it need not be appended. */ 311 if (which_library == USE_LIBCXX && LIBCXXABI != NULL) 312 num_args += 4; 313 new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args); 314 315 i = 0; 316 j = 0; 317 318 /* Copy the 0th argument, i.e., the name of the program itself. */ 319 new_decoded_options[j++] = decoded_options[i++]; 320 321 /* NOTE: We start at 1 now, not 0. */ 322 while (i < argc) 323 { 324 new_decoded_options[j] = decoded_options[i]; 325 326 /* Make sure -lstdc++ is before the math library, since libstdc++ 327 itself uses those math routines. */ 328 if (!saw_math && (args[i] & MATHLIB) && library > 0) 329 { 330 --j; 331 saw_math = &decoded_options[i]; 332 } 333 334 if (!saw_libc && (args[i] & WITHLIBC) && library > 0) 335 { 336 --j; 337 saw_libc = &decoded_options[i]; 338 } 339 340 /* Wrap foo.[chi] files in a language specification to 341 force the gcc compiler driver to run cc1plus on them. */ 342 if (args[i] & LANGSPEC) 343 { 344 const char *arg = decoded_options[i].arg; 345 int len = strlen (arg); 346 switch (arg[len - 1]) 347 { 348 case 'c': 349 generate_option (OPT_x, "c++", 1, CL_DRIVER, 350 &new_decoded_options[j++]); 351 break; 352 case 'i': 353 generate_option (OPT_x, "c++-cpp-output", 1, CL_DRIVER, 354 &new_decoded_options[j++]); 355 break; 356 case 'h': 357 generate_option (OPT_x, "c++-header", 1, CL_DRIVER, 358 &new_decoded_options[j++]); 359 break; 360 default: 361 gcc_unreachable (); 362 } 363 new_decoded_options[j++] = decoded_options[i]; 364 generate_option (OPT_x, "none", 1, CL_DRIVER, 365 &new_decoded_options[j]); 366 } 367 368 if ((args[i] & SKIPOPT) != 0) 369 --j; 370 371 i++; 372 j++; 373 } 374 375 /* Add `-lstdc++' if we haven't already done so. */ 376 if (library > 0) 377 { 378 if (need_experimental && which_library == USE_LIBSTDCXX) 379 { 380 generate_option (OPT_l, "stdc++exp", 1, CL_DRIVER, 381 &new_decoded_options[j++]); 382 ++added_libraries; 383 } 384 #ifdef HAVE_LD_STATIC_DYNAMIC 385 if (library > 1 && !static_link) 386 { 387 generate_option (OPT_Wl_, LD_STATIC_OPTION, 1, CL_DRIVER, 388 &new_decoded_options[j]); 389 j++; 390 } 391 #endif 392 if (which_library == USE_LIBCXX) 393 { 394 generate_option (OPT_l, 395 saw_profile_flag ? LIBCXX_PROFILE : LIBCXX, 1, 396 CL_DRIVER, &new_decoded_options[j]); 397 if (LIBCXXABI != NULL) 398 { 399 j++; 400 added_libraries++; 401 generate_option (OPT_l, 402 saw_profile_flag ? LIBCXXABI_PROFILE 403 : LIBCXXABI, 1, 404 CL_DRIVER, &new_decoded_options[j]); 405 } 406 } 407 else 408 generate_option (OPT_l, 409 saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1, 410 CL_DRIVER, &new_decoded_options[j]); 411 added_libraries++; 412 j++; 413 /* Add target-dependent static library, if necessary. */ 414 if ((static_link || library > 1) && LIBSTDCXX_STATIC != NULL) 415 { 416 generate_option (OPT_l, LIBSTDCXX_STATIC, 1, 417 CL_DRIVER, &new_decoded_options[j]); 418 added_libraries++; 419 j++; 420 } 421 #ifdef HAVE_LD_STATIC_DYNAMIC 422 if (library > 1 && !static_link) 423 { 424 generate_option (OPT_Wl_, LD_DYNAMIC_OPTION, 1, CL_DRIVER, 425 &new_decoded_options[j]); 426 j++; 427 } 428 #endif 429 } 430 if (saw_math) 431 new_decoded_options[j++] = *saw_math; 432 else if (library > 0 && need_math) 433 { 434 generate_option (OPT_l, 435 saw_profile_flag ? MATH_LIBRARY_PROFILE : MATH_LIBRARY, 436 1, CL_DRIVER, &new_decoded_options[j]); 437 added_libraries++; 438 j++; 439 } 440 if (saw_time) 441 new_decoded_options[j++] = *saw_time; 442 if (saw_libc) 443 new_decoded_options[j++] = *saw_libc; 444 if (shared_libgcc && !static_link) 445 generate_option (OPT_shared_libgcc, NULL, 1, CL_DRIVER, 446 &new_decoded_options[j++]); 447 448 *in_decoded_options_count = j; 449 *in_decoded_options = new_decoded_options; 450 *in_added_libraries = added_libraries; 451 } 452 453 /* Called before linking. Returns 0 on success and -1 on failure. */ 454 int lang_specific_pre_link (void) /* Not used for C++. */ 455 { 456 return 0; 457 } 458 459 /* Number of extra output files that lang_specific_pre_link may generate. */ 460 int lang_specific_extra_outfiles = 0; /* Not used for C++. */ 461
Indexes created Mon Jun 22 00:25:11 UTC 2026