gcc/fortran/gfortranspec.c

   1 /* Specific flags and argument handling of the Fortran front-end.
   2    Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003, 2004 Free Software
   3    Foundation, Inc.
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21 /* This file is copied more or less verbatim from g77.  */
  22 /* This file contains a filter for the main `gcc' driver, which is
  23    replicated for the `gfortran' driver by adding this filter.  The purpose
  24    of this filter is to be basically identical to gcc (in that
  25    it faithfully passes all of the original arguments to gcc) but,
  26    unless explicitly overridden by the user in certain ways, ensure
  27    that the needs of the language supported by this wrapper are met.
  28
  29    For GNU Fortran 95(gfortran), we do the following to the argument list
  30    before passing it to `gcc':
  31
  32    1.  Make sure `-lgfortran -lm' is at the end of the list.
  33
  34    2.  Make sure each time `-lgfortran' or `-lm' is seen, it forms
  35        part of the series `-lgfortran -lm'.
  36
  37    #1 and #2 are not done if `-nostdlib' or any option that disables
  38    the linking phase is present, or if `-xfoo' is in effect.  Note that
  39    a lack of source files or -l options disables linking.
  40
  41    This program was originally made out of gcc/cp/g++spec.c, but the
  42    way it builds the new argument list was rewritten so it is much
  43    easier to maintain, improve the way it decides to add or not add
  44    extra arguments, etc.  And several improvements were made in the
  45    handling of arguments, primarily to make it more consistent with
  46    `gcc' itself.  */
  47
  48 #include "config.h"
  49 #include "system.h"
  50 #include "gcc.h"
  51
  52 #include "coretypes.h"
  53 #include "tm.h"
  54
  55 #ifndef MATH_LIBRARY
  56 #define MATH_LIBRARY "-lm"
  57 #endif
  58
  59 #ifndef FORTRAN_INIT
  60 #define FORTRAN_INIT "-lgfortranbegin"
  61 #endif
  62
  63 #ifndef FORTRAN_LIBRARY
  64 #define FORTRAN_LIBRARY "-lgfortran"
  65 #endif
  66
  67 /* Options this driver needs to recognize, not just know how to
  68    skip over.  */
  69 typedef enum
  70 {
  71   OPTION_b,                     /* Aka --prefix. */
  72   OPTION_B,                     /* Aka --target. */
  73   OPTION_c,                     /* Aka --compile. */
  74   OPTION_E,                     /* Aka --preprocess. */
  75   OPTION_help,                  /* --help. */
  76   OPTION_i,                     /* -imacros, -include, -include-*. */
  77   OPTION_l,
  78   OPTION_L,                     /* Aka --library-directory. */
  79   OPTION_nostdlib,              /* Aka --no-standard-libraries, or
  80                                    -nodefaultlibs. */
  81   OPTION_o,                     /* Aka --output. */
  82   OPTION_S,                     /* Aka --assemble. */
  83   OPTION_syntax_only,           /* -fsyntax-only. */
  84   OPTION_v,                     /* Aka --verbose. */
  85   OPTION_version,               /* --version. */
  86   OPTION_V,                     /* Aka --use-version. */
  87   OPTION_x,                     /* Aka --language. */
  88   OPTION_                       /* Unrecognized or unimportant. */
  89 }
  90 Option;
  91
  92 /* The original argument list and related info is copied here.  */
  93 static int g77_xargc;
  94 static const char *const *g77_xargv;
  95 static void lookup_option (Option *, int *, const char **, const char *);
  96 static void append_arg (const char *);
  97
  98 /* The new argument list will be built here.  */
  99 static int g77_newargc;
 100 static const char **g77_newargv;
 101
 102 const struct spec_function lang_specific_spec_functions[] = {{0,0}};
 103
 104 /* --- This comes from gcc.c (2.8.1) verbatim: */
 105
 106 /* This defines which switch letters take arguments.  */
 107
 108 #ifndef SWITCH_TAKES_ARG
 109 #define SWITCH_TAKES_ARG(CHAR) DEFAULT_SWITCH_TAKES_ARG(CHAR)
 110 #endif
 111
 112 /* This defines which multi-letter switches take arguments.  */
 113
 114 #ifndef WORD_SWITCH_TAKES_ARG
 115 #define WORD_SWITCH_TAKES_ARG(STR) DEFAULT_WORD_SWITCH_TAKES_ARG (STR)
 116 #endif
 117
 118 /* --- End of verbatim.  */
 119
 120 /* Assumes text[0] == '-'.  Returns number of argv items that belong to
 121    (and follow) this one, an option id for options important to the
 122    caller, and a pointer to the first char of the arg, if embedded (else
 123    returns NULL, meaning no arg or it's the next argv).
 124
 125    Note that this also assumes gcc.c's pass converting long options
 126    to short ones, where available, has already been run.  */
 127
 128 static void
 129 lookup_option (Option *xopt, int *xskip, const char **xarg, const char *text)
 130 {
 131   Option opt = OPTION_;
 132   int skip;
 133   const char *arg = NULL;
 134
 135   if ((skip = SWITCH_TAKES_ARG (text[1])))
 136     skip -= (text[2] != '\0');  /* See gcc.c. */
 137
 138   if (text[1] == 'B')
 139     opt = OPTION_B, skip = (text[2] == '\0'), arg = text + 2;
 140   else if (text[1] == 'b')
 141     opt = OPTION_b, skip = (text[2] == '\0'), arg = text + 2;
 142   else if ((text[1] == 'c') && (text[2] == '\0'))
 143     opt = OPTION_c, skip = 0;
 144   else if ((text[1] == 'E') && (text[2] == '\0'))
 145     opt = OPTION_E, skip = 0;
 146   else if (text[1] == 'i')
 147     opt = OPTION_i, skip = 0;
 148   else if (text[1] == 'l')
 149     opt = OPTION_l;
 150   else if (text[1] == 'L')
 151     opt = OPTION_L, arg = text + 2;
 152   else if (text[1] == 'o')
 153     opt = OPTION_o;
 154   else if ((text[1] == 'S') && (text[2] == '\0'))
 155     opt = OPTION_S, skip = 0;
 156   else if (text[1] == 'V')
 157     opt = OPTION_V, skip = (text[2] == '\0');
 158   else if ((text[1] == 'v') && (text[2] == '\0'))
 159     opt = OPTION_v, skip = 0;
 160   else if (text[1] == 'x')
 161     opt = OPTION_x, arg = text + 2;
 162   else
 163     {
 164       if ((skip = WORD_SWITCH_TAKES_ARG (text + 1)) != 0)       /* See gcc.c. */
 165         ;
 166       else if (!strcmp (text, "-fhelp"))        /* Really --help!! */
 167         opt = OPTION_help;
 168       else if (!strcmp (text, "-nostdlib")
 169                || !strcmp (text, "-nodefaultlibs"))
 170         opt = OPTION_nostdlib;
 171       else if (!strcmp (text, "-fsyntax-only"))
 172         opt = OPTION_syntax_only;
 173       else if (!strcmp (text, "-dumpversion"))
 174         opt = OPTION_version;
 175       else if (!strcmp (text, "-fversion"))     /* Really --version!! */
 176         opt = OPTION_version;
 177       else if (!strcmp (text, "-Xlinker") || !strcmp (text, "-specs"))
 178         skip = 1;
 179       else
 180         skip = 0;
 181     }
 182
 183   if (xopt != NULL)
 184     *xopt = opt;
 185   if (xskip != NULL)
 186     *xskip = skip;
 187   if (xarg != NULL)
 188     {
 189       if ((arg != NULL) && (arg[0] == '\0'))
 190         *xarg = NULL;
 191       else
 192         *xarg = arg;
 193     }
 194 }
 195
 196 /* Append another argument to the list being built.  As long as it is
 197    identical to the corresponding arg in the original list, just increment
 198    the new arg count.  Otherwise allocate a new list, etc.  */
 199
 200 static void
 201 append_arg (const char *arg)
 202 {
 203   static int newargsize;
 204
 205 #if 0
 206   fprintf (stderr, "`%s'\n", arg);
 207 #endif
 208
 209   if (g77_newargv == g77_xargv
 210       && g77_newargc < g77_xargc
 211       && (arg == g77_xargv[g77_newargc]
 212           || !strcmp (arg, g77_xargv[g77_newargc])))
 213     {
 214       ++g77_newargc;
 215       return;                   /* Nothing new here. */
 216     }
 217
 218   if (g77_newargv == g77_xargv)
 219     {                           /* Make new arglist. */
 220       int i;
 221
 222       newargsize = (g77_xargc << 2) + 20;       /* This should handle all. */
 223       g77_newargv = (const char **) xmalloc (newargsize * sizeof (char *));
 224
 225       /* Copy what has been done so far.  */
 226       for (i = 0; i < g77_newargc; ++i)
 227         g77_newargv[i] = g77_xargv[i];
 228     }
 229
 230   if (g77_newargc == newargsize)
 231     fatal ("overflowed output arg list for `%s'", arg);
 232
 233   g77_newargv[g77_newargc++] = arg;
 234 }
 235
 236 void
 237 lang_specific_driver (int *in_argc, const char *const **in_argv,
 238                       int *in_added_libraries ATTRIBUTE_UNUSED)
 239 {
 240   int argc = *in_argc;
 241   const char *const *argv = *in_argv;
 242   int i;
 243   int verbose = 0;
 244   Option opt;
 245   int skip;
 246   const char *arg;
 247
 248   /* This will be NULL if we encounter a situation where we should not
 249      link in libf2c.  */
 250   const char *library = FORTRAN_LIBRARY;
 251
 252   /* 0 => -xnone in effect.
 253      1 => -xfoo in effect.  */
 254   int saw_speclang = 0;
 255
 256   /* 0 => initial/reset state
 257      1 => last arg was -l<library>
 258      2 => last two args were -l<library> -lm.  */
 259   int saw_library = 0;
 260
 261   /* 0 => initial/reset state
 262      1 => FORTRAN_INIT linked in */
 263   int use_init = 0;
 264
 265   /* By default, we throw on the math library if we have one.  */
 266   int need_math = (MATH_LIBRARY[0] != '\0');
 267
 268   /* The number of input and output files in the incoming arg list.  */
 269   int n_infiles = 0;
 270   int n_outfiles = 0;
 271
 272 #if 0
 273   fprintf (stderr, "Incoming:");
 274   for (i = 0; i < argc; i++)
 275     fprintf (stderr, " %s", argv[i]);
 276   fprintf (stderr, "\n");
 277 #endif
 278
 279   g77_xargc = argc;
 280   g77_xargv = argv;
 281   g77_newargc = 0;
 282   g77_newargv = (const char **) argv;
 283
 284   /* First pass through arglist.
 285
 286      If -nostdlib or a "turn-off-linking" option is anywhere in the
 287      command line, don't do any library-option processing (except
 288      relating to -x).  Also, if -v is specified, but no other options
 289      that do anything special (allowing -V version, etc.), remember
 290      to add special stuff to make gcc command actually invoke all
 291      the different phases of the compilation process so all the version
 292      numbers can be seen.
 293
 294      Also, here is where all problems with missing arguments to options
 295      are caught.  If this loop is exited normally, it means all options
 296      have the appropriate number of arguments as far as the rest of this
 297      program is concerned.  */
 298
 299   for (i = 1; i < argc; ++i)
 300     {
 301       if ((argv[i][0] == '+') && (argv[i][1] == 'e'))
 302         {
 303           continue;
 304         }
 305
 306       if ((argv[i][0] != '-') || (argv[i][1] == '\0'))
 307         {
 308           ++n_infiles;
 309           continue;
 310         }
 311
 312       lookup_option (&opt, &skip, NULL, argv[i]);
 313
 314       switch (opt)
 315         {
 316         case OPTION_nostdlib:
 317         case OPTION_c:
 318         case OPTION_S:
 319         case OPTION_syntax_only:
 320         case OPTION_E:
 321           /* These options disable linking entirely or linking of the
 322              standard libraries.  */
 323           library = 0;
 324           break;
 325
 326         case OPTION_l:
 327           ++n_infiles;
 328           break;
 329
 330         case OPTION_o:
 331           ++n_outfiles;
 332           break;
 333
 334         case OPTION_v:
 335           verbose = 1;
 336           break;
 337
 338         case OPTION_b:
 339         case OPTION_B:
 340         case OPTION_L:
 341         case OPTION_i:
 342         case OPTION_V:
 343           /* These options are useful in conjunction with -v to get
 344              appropriate version info.  */
 345           break;
 346
 347         case OPTION_version:
 348           printf ("\
 349 GNU Fortran 95 (GCC %s)\n\
 350 Copyright (C) 2003 Free Software Foundation, Inc.\n\
 351 \n\
 352 GNU Fortran comes with NO WARRANTY, to the extent permitted by law.\n\
 353 You may redistribute copies of GNU Fortran\n\
 354 under the terms of the GNU General Public License.\n\
 355 For more information about these matters, see the file named COPYING\n\
 356 ", version_string);
 357           exit (0);
 358           break;
 359
 360         case OPTION_help:
 361           /* Let gcc.c handle this, as it has a really
 362              cool facility for handling --help and --verbose --help.  */
 363           return;
 364
 365         default:
 366           break;
 367         }
 368
 369       /* This is the one place we check for missing arguments in the
 370          program.  */
 371
 372       if (i + skip < argc)
 373         i += skip;
 374       else
 375         fatal ("argument to `%s' missing", argv[i]);
 376     }
 377
 378   if ((n_outfiles != 0) && (n_infiles == 0))
 379     fatal ("no input files; unwilling to write output files");
 380
 381   /* If there are no input files, no need for the library.  */
 382   if (n_infiles == 0)
 383     library = 0;
 384
 385   /* Second pass through arglist, transforming arguments as appropriate.  */
 386
 387   append_arg (argv[0]);         /* Start with command name, of course. */
 388
 389   for (i = 1; i < argc; ++i)
 390     {
 391       if (argv[i][0] == '\0')
 392         {
 393           append_arg (argv[i]); /* Interesting.  Just append as is. */
 394           continue;
 395         }
 396
 397       if ((argv[i][0] == '-') && (argv[i][1] == 'M'))
 398         {
 399           char *p;
 400
 401           if (argv[i][2] == '\0')
 402             {
 403               p = xmalloc (strlen (argv[i + 1]) + 2);
 404               p[0] = '-';
 405               p[1] = 'J';
 406               strcpy (&p[2], argv[i + 1]);
 407               i++;
 408             }
 409           else
 410             {
 411               p = xmalloc (strlen (argv[i]) + 1);
 412               strcpy (p, argv[i]);
 413             }
 414           append_arg (p);
 415           continue;
 416         }
 417
 418       if ((argv[i][0] == '-') && (argv[i][1] != 'l'))
 419         {
 420           /* Not a filename or library. */
 421
 422           if (saw_library == 1 && need_math)    /* -l<library>. */
 423             append_arg (MATH_LIBRARY);
 424
 425           saw_library = 0;
 426
 427           lookup_option (&opt, &skip, &arg, argv[i]);
 428
 429           if (argv[i][1] == '\0')
 430             {
 431               append_arg (argv[i]);     /* "-" == Standard input. */
 432               continue;
 433             }
 434
 435           if (opt == OPTION_x)
 436             {
 437               /* Track input language. */
 438               const char *lang;
 439
 440               if (arg == NULL)
 441                 lang = argv[i + 1];
 442               else
 443                 lang = arg;
 444
 445               saw_speclang = (strcmp (lang, "none") != 0);
 446             }
 447
 448           append_arg (argv[i]);
 449
 450           for (; skip != 0; --skip)
 451             append_arg (argv[++i]);
 452
 453           continue;
 454         }
 455
 456       /* A filename/library, not an option. */
 457
 458       if (saw_speclang)
 459         saw_library = 0;        /* -xfoo currently active. */
 460       else
 461         {                       /* -lfoo or filename. */
 462           if (strcmp (argv[i], MATH_LIBRARY) == 0)
 463             {
 464               if (saw_library == 1)
 465                 saw_library = 2;        /* -l<library> -lm. */
 466               else
 467                 {
 468                   if (0 == use_init)
 469                     {
 470                       append_arg (FORTRAN_INIT);
 471                       use_init = 1;
 472                     }
 473                   append_arg (FORTRAN_LIBRARY);
 474                 }
 475             }
 476           else if (strcmp (argv[i], FORTRAN_LIBRARY) == 0)
 477             saw_library = 1;    /* -l<library>. */
 478           else
 479             {                   /* Other library, or filename. */
 480               if (saw_library == 1 && need_math)
 481                 append_arg (MATH_LIBRARY);
 482               saw_library = 0;
 483             }
 484         }
 485       append_arg (argv[i]);
 486     }
 487
 488   /* Append `-lg2c -lm' as necessary.  */
 489
 490   if (library)
 491     {                           /* Doing a link and no -nostdlib. */
 492       if (saw_speclang)
 493         append_arg ("-xnone");
 494
 495       switch (saw_library)
 496         {
 497         case 0:
 498           if (0 == use_init)
 499             {
 500               append_arg (FORTRAN_INIT);
 501               use_init = 1;
 502             }
 503           append_arg (library);
 504         case 1:
 505           if (need_math)
 506             append_arg (MATH_LIBRARY);
 507         default:
 508           break;
 509         }
 510     }
 511
 512 #ifdef ENABLE_SHARED_LIBGCC
 513   if (library)
 514     {
 515       int i;
 516
 517       for (i = 1; i < g77_newargc; i++)
 518         if (g77_newargv[i][0] == '-')
 519           if (strcmp (g77_newargv[i], "-static-libgcc") == 0
 520               || strcmp (g77_newargv[i], "-static") == 0)
 521             break;
 522
 523       if (i == g77_newargc)
 524         append_arg ("-shared-libgcc");
 525     }
 526
 527 #endif
 528
 529   if (verbose && g77_newargv != g77_xargv)
 530     {
 531       fprintf (stderr, "Driving:");
 532       for (i = 0; i < g77_newargc; i++)
 533         fprintf (stderr, " %s", g77_newargv[i]);
 534       fprintf (stderr, "\n");
 535     }
 536
 537   *in_argc = g77_newargc;
 538   *in_argv = g77_newargv;
 539 }
 540
 541 /* Called before linking.  Returns 0 on success and -1 on failure. */
 542 int
 543 lang_specific_pre_link (void)   /* Not used for F77. */
 544 {
 545   return 0;
 546 }
 547
 548 /* Number of extra output files that lang_specific_pre_link may generate. */
 549 int lang_specific_extra_outfiles = 0;   /* Not used for F77. */