gcc/cp/g++spec.c

   1 /* Specific flags and argument handling of the C++ front end.
   2    Copyright (C) 1996-2021 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
  35 #ifndef MATH_LIBRARY
  36 #define MATH_LIBRARY "m"
  37 #endif
  38 #ifndef MATH_LIBRARY_PROFILE
  39 #define MATH_LIBRARY_PROFILE MATH_LIBRARY
  40 #endif
  41
  42 #ifndef LIBSTDCXX
  43 #define LIBSTDCXX "stdc++"
  44 #endif
  45 #ifndef LIBSTDCXX_PROFILE
  46 #define LIBSTDCXX_PROFILE LIBSTDCXX
  47 #endif
  48 #ifndef LIBSTDCXX_STATIC
  49 #define LIBSTDCXX_STATIC NULL
  50 #endif
  51
  52 #ifndef LIBCXX
  53 #define LIBCXX "c++"
  54 #endif
  55 #ifndef LIBCXX_PROFILE
  56 #define LIBCXX_PROFILE LIBCXX
  57 #endif
  58 #ifndef LIBCXX_STATIC
  59 #define LIBCXX_STATIC NULL
  60 #endif
  61
  62 #ifndef LIBCXXABI
  63 #define LIBCXXABI "c++abi"
  64 #endif
  65 #ifndef LIBCXXABI_PROFILE
  66 #define LIBCXXABI_PROFILE LIBCXXABI
  67 #endif
  68 #ifndef LIBCXXABI_STATIC
  69 #define LIBCXXABI_STATIC NULL
  70 #endif
  71
  72 /* The values used here must match those of the stdlib_kind enumeration
  73    in c.opt.  */
  74 enum stdcxxlib_kind
  75 {
  76   USE_LIBSTDCXX = 1,
  77   USE_LIBCXX = 2
  78 };
  79
  80 void
  81 lang_specific_driver (struct cl_decoded_option **in_decoded_options,
  82                       unsigned int *in_decoded_options_count,
  83                       int *in_added_libraries)
  84 {
  85   unsigned int i, j;
  86
  87   /* If nonzero, the user gave us the `-p' or `-pg' flag.  */
  88   int saw_profile_flag = 0;
  89
  90   /* What action to take for the c++ runtime library:
  91     -1  means we should not link it in.
  92      0  means we should link it if it is needed.
  93      1  means it is needed and should be linked in.
  94      2  means it is needed but should be linked statically.  */
  95   int library = 0;
  96
  97   /* Which c++ runtime library to link.  */
  98   stdcxxlib_kind which_library = USE_LIBSTDCXX;
  99
 100   /* The number of arguments being added to what's in argv, other than
 101      libraries.  We use this to track the number of times we've inserted
 102      -xc++/-xnone.  */
 103   int added = 0;
 104
 105   /* The new argument list will be contained in this.  */
 106   struct cl_decoded_option *new_decoded_options;
 107
 108   /* Nonzero if we saw a `-xfoo' language specification on the
 109      command line.  Used to avoid adding our own -xc++ if the user
 110      already gave a language for the file.  */
 111   int saw_speclang = 0;
 112
 113   /* "-lm" or "-lmath" if it appears on the command line.  */
 114   const struct cl_decoded_option *saw_math = NULL;
 115
 116   /* "-lrt" or eqivalent if it appears on the command line.  */
 117   const struct cl_decoded_option *saw_time = NULL;
 118
 119   /* "-lc" if it appears on the command line.  */
 120   const struct cl_decoded_option *saw_libc = NULL;
 121
 122   /* An array used to flag each argument that needs a bit set for
 123      LANGSPEC, MATHLIB, or WITHLIBC.  */
 124   int *args;
 125
 126   /* By default, we throw on the math library if we have one.  */
 127   int need_math = (MATH_LIBRARY[0] != '\0');
 128
 129   /* True if we saw -static.  */
 130   int static_link = 0;
 131
 132   /* True if we should add -shared-libgcc to the command-line.  */
 133   int shared_libgcc = 1;
 134
 135   /* The total number of arguments with the new stuff.  */
 136   unsigned int argc;
 137
 138   /* The argument list.  */
 139   struct cl_decoded_option *decoded_options;
 140
 141   /* The number of libraries added in.  */
 142   int added_libraries;
 143
 144   /* The total number of arguments with the new stuff.  */
 145   unsigned int num_args = 1;
 146
 147   argc = *in_decoded_options_count;
 148   decoded_options = *in_decoded_options;
 149   added_libraries = *in_added_libraries;
 150
 151   args = XCNEWVEC (int, argc);
 152
 153   for (i = 1; i < argc; i++)
 154     {
 155       const char *arg = decoded_options[i].arg;
 156       if (decoded_options[i].errors & CL_ERR_MISSING_ARG)
 157         continue; /* Avoid examining arguments of options missing them.  */
 158
 159       switch (decoded_options[i].opt_index)
 160         {
 161         case OPT_nostdlib:
 162         case OPT_nodefaultlibs:
 163           library = -1;
 164           break;
 165
 166         case OPT_l:
 167           if (strcmp (arg, MATH_LIBRARY) == 0)
 168             {
 169               args[i] |= MATHLIB;
 170               need_math = 0;
 171             }
 172           else if (strcmp (arg, "c") == 0)
 173             args[i] |= WITHLIBC;
 174           else
 175             /* Unrecognized libraries (e.g. -lfoo) may require libstdc++.  */
 176             library = (library == 0) ? 1 : library;
 177           break;
 178
 179         case OPT_pg:
 180         case OPT_p:
 181           saw_profile_flag++;
 182           break;
 183
 184         case OPT_x:
 185           if (library == 0
 186               && (strcmp (arg, "c++") == 0
 187                   || strcmp (arg, "c++-cpp-output") == 0
 188                   || strcmp (arg, "objective-c++") == 0
 189                   || strcmp (arg, "objective-c++-cpp-output") == 0))
 190             library = 1;
 191
 192           saw_speclang = 1;
 193           break;
 194
 195         case OPT_Xlinker:
 196         case OPT_Wl_:
 197           /* Arguments that go directly to the linker might be .o files,
 198              or something, and so might cause libstdc++ to be needed.  */
 199           if (library == 0)
 200             library = 1;
 201           break;
 202
 203         case OPT_c:
 204         case OPT_r:
 205         case OPT_S:
 206         case OPT_E:
 207         case OPT_M:
 208         case OPT_MM:
 209         case OPT_fsyntax_only:
 210           /* Don't specify libraries if we won't link, since that would
 211              cause a warning.  */
 212           library = -1;
 213           break;
 214
 215         case OPT_static:
 216           static_link = 1;
 217           break;
 218
 219         case OPT_static_libgcc:
 220           shared_libgcc = 0;
 221           break;
 222
 223         case OPT_static_libstdc__:
 224           library = library >= 0 ? 2 : library;
 225           args[i] |= SKIPOPT;
 226           break;
 227
 228         case OPT_stdlib_:
 229           which_library = (stdcxxlib_kind) decoded_options[i].value;
 230           break;
 231
 232         case OPT_SPECIAL_input_file:
 233           {
 234             int len;
 235
 236             /* We don't do this anymore, since we don't get them with minus
 237                signs on them.  */
 238             if (arg[0] == '\0' || arg[1] == '\0')
 239               continue;
 240
 241             if (saw_speclang)
 242               {
 243                 saw_speclang = 0;
 244                 continue;
 245               }
 246
 247             /* If the filename ends in .[chi], put options around it.
 248                But not if a specified -x option is currently active.  */
 249             len = strlen (arg);
 250             if (len > 2
 251                 && (arg[len - 1] == 'c'
 252                     || arg[len - 1] == 'i'
 253                     || arg[len - 1] == 'h')
 254                 && arg[len - 2] == '.')
 255               {
 256                 args[i] |= LANGSPEC;
 257                 added += 2;
 258               }
 259
 260             /* If we don't know that this is a header file, we might
 261                need to be linking in the libraries.  */
 262             if (library == 0)
 263               {
 264                 if ((len <= 2 || strcmp (arg + (len - 2), ".H") != 0)
 265                     && (len <= 2 || strcmp (arg + (len - 2), ".h") != 0)
 266                     && (len <= 4 || strcmp (arg + (len - 4), ".hpp") != 0)
 267                     && (len <= 3 || strcmp (arg + (len - 3), ".hp") != 0)
 268                     && (len <= 4 || strcmp (arg + (len - 4), ".hxx") != 0)
 269                     && (len <= 4 || strcmp (arg + (len - 4), ".h++") != 0)
 270                     && (len <= 4 || strcmp (arg + (len - 4), ".HPP") != 0)
 271                     && (len <= 4 || strcmp (arg + (len - 4), ".tcc") != 0)
 272                     && (len <= 3 || strcmp (arg + (len - 3), ".hh") != 0))
 273                   library = 1;
 274               }
 275           }
 276           break;
 277         }
 278     }
 279
 280   /* There's no point adding -shared-libgcc if we don't have a shared
 281      libgcc.  */
 282 #ifndef ENABLE_SHARED_LIBGCC
 283   shared_libgcc = 0;
 284 #endif
 285
 286   /* Add one for shared_libgcc or extra static library.  */
 287   num_args = argc + added + need_math + (library > 0) * 4 + 1;
 288   /* For libc++, on most platforms, the ABI library (usually called libc++abi)
 289      is provided as a separate DSO, which we must also append.
 290      However, a platform might have the ability to forward the ABI library
 291      from libc++, or combine it in some other way; in that case, LIBCXXABI
 292      should be set to NULL to signal that it need not be appended.  */
 293   if (which_library == USE_LIBCXX && LIBCXXABI != NULL)
 294     num_args += 4;
 295   new_decoded_options = XNEWVEC (struct cl_decoded_option, num_args);
 296
 297   i = 0;
 298   j = 0;
 299
 300   /* Copy the 0th argument, i.e., the name of the program itself.  */
 301   new_decoded_options[j++] = decoded_options[i++];
 302
 303   /* NOTE: We start at 1 now, not 0.  */
 304   while (i < argc)
 305     {
 306       new_decoded_options[j] = decoded_options[i];
 307
 308       /* Make sure -lstdc++ is before the math library, since libstdc++
 309          itself uses those math routines.  */
 310       if (!saw_math && (args[i] & MATHLIB) && library > 0)
 311         {
 312           --j;
 313           saw_math = &decoded_options[i];
 314         }
 315
 316       if (!saw_libc && (args[i] & WITHLIBC) && library > 0)
 317         {
 318           --j;
 319           saw_libc = &decoded_options[i];
 320         }
 321
 322       /* Wrap foo.[chi] files in a language specification to
 323          force the gcc compiler driver to run cc1plus on them.  */
 324       if (args[i] & LANGSPEC)
 325         {
 326           const char *arg = decoded_options[i].arg;
 327           int len = strlen (arg);
 328           switch (arg[len - 1])
 329             {
 330             case 'c':
 331               generate_option (OPT_x, "c++", 1, CL_DRIVER,
 332                                &new_decoded_options[j++]);
 333               break;
 334             case 'i':
 335               generate_option (OPT_x, "c++-cpp-output", 1, CL_DRIVER,
 336                                &new_decoded_options[j++]);
 337               break;
 338             case 'h':
 339               generate_option (OPT_x, "c++-header", 1, CL_DRIVER,
 340                                &new_decoded_options[j++]);
 341               break;
 342             default:
 343               gcc_unreachable ();
 344             }
 345           new_decoded_options[j++] = decoded_options[i];
 346           generate_option (OPT_x, "none", 1, CL_DRIVER,
 347                            &new_decoded_options[j]);
 348         }
 349
 350       if ((args[i] & SKIPOPT) != 0)
 351         --j;
 352
 353       i++;
 354       j++;
 355     }
 356
 357   /* Add `-lstdc++' if we haven't already done so.  */
 358   if (library > 0)
 359     {
 360 #ifdef HAVE_LD_STATIC_DYNAMIC
 361       if (library > 1 && !static_link)
 362         {
 363           generate_option (OPT_Wl_, LD_STATIC_OPTION, 1, CL_DRIVER,
 364                            &new_decoded_options[j]);
 365           j++;
 366         }
 367 #endif
 368       if (which_library == USE_LIBCXX)
 369         {
 370           generate_option (OPT_l,
 371                          saw_profile_flag ? LIBCXX_PROFILE : LIBCXX, 1,
 372                          CL_DRIVER, &new_decoded_options[j]);
 373           if (LIBCXXABI != NULL)
 374             {
 375               j++;
 376               added_libraries++;
 377               generate_option (OPT_l,
 378                                saw_profile_flag ? LIBCXXABI_PROFILE
 379                                                 : LIBCXXABI, 1,
 380                                CL_DRIVER, &new_decoded_options[j]);
 381             }
 382         }
 383       else
 384         generate_option (OPT_l,
 385                          saw_profile_flag ? LIBSTDCXX_PROFILE : LIBSTDCXX, 1,
 386                          CL_DRIVER, &new_decoded_options[j]);
 387       added_libraries++;
 388       j++;
 389       /* Add target-dependent static library, if necessary.  */
 390       if ((static_link || library > 1) && LIBSTDCXX_STATIC != NULL)
 391         {
 392           generate_option (OPT_l, LIBSTDCXX_STATIC, 1,
 393                            CL_DRIVER, &new_decoded_options[j]);
 394           added_libraries++;
 395           j++;
 396         }
 397 #ifdef HAVE_LD_STATIC_DYNAMIC
 398       if (library > 1 && !static_link)
 399         {
 400           generate_option (OPT_Wl_, LD_DYNAMIC_OPTION, 1, CL_DRIVER,
 401                            &new_decoded_options[j]);
 402           j++;
 403         }
 404 #endif
 405     }
 406   if (saw_math)
 407     new_decoded_options[j++] = *saw_math;
 408   else if (library > 0 && need_math)
 409     {
 410       generate_option (OPT_l,
 411                        saw_profile_flag ? MATH_LIBRARY_PROFILE : MATH_LIBRARY,
 412                        1, CL_DRIVER, &new_decoded_options[j]);
 413       added_libraries++;
 414       j++;
 415     }
 416   if (saw_time)
 417     new_decoded_options[j++] = *saw_time;
 418   if (saw_libc)
 419     new_decoded_options[j++] = *saw_libc;
 420   if (shared_libgcc && !static_link)
 421     generate_option (OPT_shared_libgcc, NULL, 1, CL_DRIVER,
 422                      &new_decoded_options[j++]);
 423
 424   *in_decoded_options_count = j;
 425   *in_decoded_options = new_decoded_options;
 426   *in_added_libraries = added_libraries;
 427 }
 428
 429 /* Called before linking.  Returns 0 on success and -1 on failure.  */
 430 int lang_specific_pre_link (void)  /* Not used for C++.  */
 431 {
 432   return 0;
 433 }
 434
 435 /* Number of extra output files that lang_specific_pre_link may generate.  */
 436 int lang_specific_extra_outfiles = 0;  /* Not used for C++.  */