gcc/fortran/options.c

   1 /* Parse and display command line options.
   2    Copyright (C) 2000-2017 Free Software Foundation, Inc.
   3    Contributed by Andy Vaught
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "target.h"
  25 #include "tree.h"
  26 #include "gfortran.h"
  27 #include "diagnostic.h" /* For global_dc.  */
  28 #include "opts.h"
  29 #include "toplev.h"  /* For save_decoded_options.  */
  30 #include "cpp.h"
  31 #include "langhooks.h"
  32
  33 gfc_option_t gfc_option;
  34
  35
  36 /* Set flags that control warnings and errors for different
  37    Fortran standards to their default values.  Keep in sync with
  38    libgfortran/runtime/compile_options.c (init_compile_options).  */
  39
  40 static void
  41 set_default_std_flags (void)
  42 {
  43   gfc_option.allow_std = GFC_STD_F95_OBS | GFC_STD_F95_DEL
  44     | GFC_STD_F2003 | GFC_STD_F2008 | GFC_STD_F95 | GFC_STD_F77
  45     | GFC_STD_F2008_OBS | GFC_STD_F2008_TS | GFC_STD_GNU | GFC_STD_LEGACY;
  46   gfc_option.warn_std = GFC_STD_F95_DEL | GFC_STD_LEGACY;
  47 }
  48
  49
  50 /* Set all the DEC extension flags.  */
  51
  52 static void
  53 set_dec_flags (int value)
  54 {
  55   if (value)
  56     {
  57       /* Allow legacy code without warnings.  */
  58       gfc_option.allow_std |= GFC_STD_F95_OBS | GFC_STD_F95_DEL
  59         | GFC_STD_GNU | GFC_STD_LEGACY;
  60       gfc_option.warn_std &= ~(GFC_STD_LEGACY | GFC_STD_F95_DEL);
  61     }
  62
  63   /* Set other DEC compatibility extensions.  */
  64   flag_dollar_ok |= value;
  65   flag_cray_pointer |= value;
  66   flag_dec_structure |= value;
  67   flag_dec_intrinsic_ints |= value;
  68   flag_dec_static |= value;
  69   flag_dec_math |= value;
  70 }
  71
  72
  73 /* Return language mask for Fortran options.  */
  74
  75 unsigned int
  76 gfc_option_lang_mask (void)
  77 {
  78   return CL_Fortran;
  79 }
  80
  81 /* Initialize options structure OPTS.  */
  82
  83 void
  84 gfc_init_options_struct (struct gcc_options *opts)
  85 {
  86   opts->x_flag_errno_math = 0;
  87   opts->frontend_set_flag_errno_math = true;
  88   opts->x_flag_associative_math = -1;
  89   opts->frontend_set_flag_associative_math = true;
  90 }
  91
  92 /* Get ready for options handling. Keep in sync with
  93    libgfortran/runtime/compile_options.c (init_compile_options).  */
  94
  95 void
  96 gfc_init_options (unsigned int decoded_options_count,
  97                   struct cl_decoded_option *decoded_options)
  98 {
  99   gfc_source_file = NULL;
 100   gfc_option.module_dir = NULL;
 101   gfc_option.source_form = FORM_UNKNOWN;
 102   gfc_option.max_continue_fixed = 255;
 103   gfc_option.max_continue_free = 255;
 104   gfc_option.max_identifier_length = GFC_MAX_SYMBOL_LEN;
 105   gfc_option.max_errors = 25;
 106
 107   gfc_option.flag_preprocessed = 0;
 108   gfc_option.flag_d_lines = -1;
 109   gfc_option.flag_init_integer = GFC_INIT_INTEGER_OFF;
 110   gfc_option.flag_init_integer_value = 0;
 111   gfc_option.flag_init_logical = GFC_INIT_LOGICAL_OFF;
 112   gfc_option.flag_init_character = GFC_INIT_CHARACTER_OFF;
 113   gfc_option.flag_init_character_value = (char)0;
 114
 115   gfc_option.fpe = 0;
 116   /* All except GFC_FPE_INEXACT.  */
 117   gfc_option.fpe_summary = GFC_FPE_INVALID | GFC_FPE_DENORMAL
 118                            | GFC_FPE_ZERO | GFC_FPE_OVERFLOW
 119                            | GFC_FPE_UNDERFLOW;
 120   gfc_option.rtcheck = 0;
 121
 122   /* ??? Wmissing-include-dirs is disabled by default in C/C++ but
 123      enabled by default in Fortran.  Ideally, we should express this
 124      in .opt, but that is not supported yet.  */
 125   if (!global_options_set.x_cpp_warn_missing_include_dirs)
 126     global_options.x_cpp_warn_missing_include_dirs = 1;
 127
 128   set_dec_flags (0);
 129
 130   set_default_std_flags ();
 131
 132   /* Initialize cpp-related options.  */
 133   gfc_cpp_init_options (decoded_options_count, decoded_options);
 134   gfc_diagnostics_init ();
 135 }
 136
 137
 138 /* Determine the source form from the filename extension.  We assume
 139    case insensitivity.  */
 140
 141 static gfc_source_form
 142 form_from_filename (const char *filename)
 143 {
 144   static const struct
 145   {
 146     const char *extension;
 147     gfc_source_form form;
 148   }
 149   exttype[] =
 150   {
 151     {
 152     ".f90", FORM_FREE}
 153     ,
 154     {
 155     ".f95", FORM_FREE}
 156     ,
 157     {
 158     ".f03", FORM_FREE}
 159     ,
 160     {
 161     ".f08", FORM_FREE}
 162     ,
 163     {
 164     ".f", FORM_FIXED}
 165     ,
 166     {
 167     ".for", FORM_FIXED}
 168     ,
 169     {
 170     ".ftn", FORM_FIXED}
 171     ,
 172     {
 173     "", FORM_UNKNOWN}
 174   };            /* sentinel value */
 175
 176   gfc_source_form f_form;
 177   const char *fileext;
 178   int i;
 179
 180   /* Find end of file name.  Note, filename is either a NULL pointer or
 181      a NUL terminated string.  */
 182   i = 0;
 183   while (filename[i] != '\0')
 184     i++;
 185
 186   /* Find last period.  */
 187   while (i >= 0 && (filename[i] != '.'))
 188     i--;
 189
 190   /* Did we see a file extension?  */
 191   if (i < 0)
 192     return FORM_UNKNOWN; /* Nope  */
 193
 194   /* Get file extension and compare it to others.  */
 195   fileext = &(filename[i]);
 196
 197   i = -1;
 198   f_form = FORM_UNKNOWN;
 199   do
 200     {
 201       i++;
 202       if (strcasecmp (fileext, exttype[i].extension) == 0)
 203         {
 204           f_form = exttype[i].form;
 205           break;
 206         }
 207     }
 208   while (exttype[i].form != FORM_UNKNOWN);
 209
 210   return f_form;
 211 }
 212
 213
 214 /* Finalize commandline options.  */
 215
 216 bool
 217 gfc_post_options (const char **pfilename)
 218 {
 219   const char *filename = *pfilename, *canon_source_file = NULL;
 220   char *source_path;
 221   int i;
 222
 223   /* Excess precision other than "fast" requires front-end
 224      support.  */
 225   if (flag_excess_precision_cmdline == EXCESS_PRECISION_STANDARD)
 226     sorry ("-fexcess-precision=standard for Fortran");
 227   flag_excess_precision_cmdline = EXCESS_PRECISION_FAST;
 228
 229   /* Fortran allows associative math - but we cannot reassociate if
 230      we want traps or signed zeros. Cf. also flag_protect_parens.  */
 231   if (flag_associative_math == -1)
 232     flag_associative_math = (!flag_trapping_math && !flag_signed_zeros);
 233
 234   if (flag_protect_parens == -1)
 235     flag_protect_parens = !optimize_fast;
 236
 237   /* -Ofast sets implies -fstack-arrays unless an explicit size is set for
 238      stack arrays.  */
 239   if (flag_stack_arrays == -1 && flag_max_stack_var_size == -2)
 240     flag_stack_arrays = optimize_fast;
 241
 242   /* By default, disable (re)allocation during assignment for -std=f95,
 243      and enable it for F2003/F2008/GNU/Legacy.  */
 244   if (flag_realloc_lhs == -1)
 245     {
 246       if (gfc_option.allow_std & GFC_STD_F2003)
 247         flag_realloc_lhs = 1;
 248       else
 249         flag_realloc_lhs = 0;
 250     }
 251
 252   /* -fbounds-check is equivalent to -fcheck=bounds */
 253   if (flag_bounds_check)
 254     gfc_option.rtcheck |= GFC_RTCHECK_BOUNDS;
 255
 256   if (flag_compare_debug)
 257     flag_dump_fortran_original = 0;
 258
 259   /* Make -fmax-errors visible to gfortran's diagnostic machinery.  */
 260   if (global_options_set.x_flag_max_errors)
 261     gfc_option.max_errors = flag_max_errors;
 262
 263   /* Verify the input file name.  */
 264   if (!filename || strcmp (filename, "-") == 0)
 265     {
 266       filename = "";
 267     }
 268
 269   if (gfc_option.flag_preprocessed)
 270     {
 271       /* For preprocessed files, if the first tokens are of the form # NUM.
 272          handle the directives so we know the original file name.  */
 273       gfc_source_file = gfc_read_orig_filename (filename, &canon_source_file);
 274       if (gfc_source_file == NULL)
 275         gfc_source_file = filename;
 276       else
 277         *pfilename = gfc_source_file;
 278     }
 279   else
 280     gfc_source_file = filename;
 281
 282   if (canon_source_file == NULL)
 283     canon_source_file = gfc_source_file;
 284
 285   /* Adds the path where the source file is to the list of include files.  */
 286
 287   i = strlen (canon_source_file);
 288   while (i > 0 && !IS_DIR_SEPARATOR (canon_source_file[i]))
 289     i--;
 290
 291   if (i != 0)
 292     {
 293       source_path = (char *) alloca (i + 1);
 294       memcpy (source_path, canon_source_file, i);
 295       source_path[i] = 0;
 296       gfc_add_include_path (source_path, true, true, true);
 297     }
 298   else
 299     gfc_add_include_path (".", true, true, true);
 300
 301   if (canon_source_file != gfc_source_file)
 302     free (CONST_CAST (char *, canon_source_file));
 303
 304   /* Decide which form the file will be read in as.  */
 305
 306   if (gfc_option.source_form != FORM_UNKNOWN)
 307     gfc_current_form = gfc_option.source_form;
 308   else
 309     {
 310       gfc_current_form = form_from_filename (filename);
 311
 312       if (gfc_current_form == FORM_UNKNOWN)
 313         {
 314           gfc_current_form = FORM_FREE;
 315           gfc_warning_now (0, "Reading file %qs as free form",
 316                            (filename[0] == '\0') ? "<stdin>" : filename);
 317         }
 318     }
 319
 320   /* If the user specified -fd-lines-as-{code|comments} verify that we're
 321      in fixed form.  */
 322   if (gfc_current_form == FORM_FREE)
 323     {
 324       if (gfc_option.flag_d_lines == 0)
 325         gfc_warning_now (0, "%<-fd-lines-as-comments%> has no effect "
 326                            "in free form");
 327       else if (gfc_option.flag_d_lines == 1)
 328         gfc_warning_now (0, "%<-fd-lines-as-code%> has no effect in free form");
 329
 330       if (warn_line_truncation == -1)
 331           warn_line_truncation = 1;
 332
 333       /* Enable -Werror=line-truncation when -Werror and -Wno-error have
 334          not been set.  */
 335       if (warn_line_truncation && !global_options_set.x_warnings_are_errors
 336           && (global_dc->classify_diagnostic[OPT_Wline_truncation] ==
 337               DK_UNSPECIFIED))
 338         diagnostic_classify_diagnostic (global_dc, OPT_Wline_truncation,
 339                                         DK_ERROR, UNKNOWN_LOCATION);
 340     }
 341   else
 342     {
 343       /* With -fdec, set -fd-lines-as-comments by default in fixed form.  */
 344       if (flag_dec && gfc_option.flag_d_lines == -1)
 345         gfc_option.flag_d_lines = 0;
 346
 347       if (warn_line_truncation == -1)
 348         warn_line_truncation = 0;
 349     }
 350
 351   /* If -pedantic, warn about the use of GNU extensions.  */
 352   if (pedantic && (gfc_option.allow_std & GFC_STD_GNU) != 0)
 353     gfc_option.warn_std |= GFC_STD_GNU;
 354   /* -std=legacy -pedantic is effectively -std=gnu.  */
 355   if (pedantic && (gfc_option.allow_std & GFC_STD_LEGACY) != 0)
 356     gfc_option.warn_std |= GFC_STD_F95_OBS | GFC_STD_F95_DEL | GFC_STD_LEGACY;
 357
 358   /* If the user didn't explicitly specify -f(no)-second-underscore we
 359      use it if we're trying to be compatible with f2c, and not
 360      otherwise.  */
 361   if (flag_second_underscore == -1)
 362     flag_second_underscore = flag_f2c;
 363
 364   if (!flag_automatic && flag_max_stack_var_size != -2
 365       && flag_max_stack_var_size != 0)
 366     gfc_warning_now (0, "Flag %<-fno-automatic%> overwrites %<-fmax-stack-var-size=%d%>",
 367                      flag_max_stack_var_size);
 368   else if (!flag_automatic && flag_recursive)
 369     gfc_warning_now (0, "Flag %<-fno-automatic%> overwrites %<-frecursive%>");
 370   else if (!flag_automatic && flag_openmp)
 371     gfc_warning_now (0, "Flag %<-fno-automatic%> overwrites %<-frecursive%> implied by "
 372                      "%<-fopenmp%>");
 373   else if (flag_max_stack_var_size != -2 && flag_recursive)
 374     gfc_warning_now (0, "Flag %<-frecursive%> overwrites %<-fmax-stack-var-size=%d%>",
 375                      flag_max_stack_var_size);
 376   else if (flag_max_stack_var_size != -2 && flag_openmp)
 377     gfc_warning_now (0, "Flag %<-fmax-stack-var-size=%d%> overwrites %<-frecursive%> "
 378                      "implied by %<-fopenmp%>", flag_max_stack_var_size);
 379
 380   /* Implement -frecursive as -fmax-stack-var-size=-1.  */
 381   if (flag_recursive)
 382     flag_max_stack_var_size = -1;
 383
 384   /* Implied -frecursive; implemented as -fmax-stack-var-size=-1.  */
 385   if (flag_max_stack_var_size == -2 && flag_openmp && flag_automatic)
 386     {
 387       flag_recursive = 1;
 388       flag_max_stack_var_size = -1;
 389     }
 390
 391   /* Set flag_stack_arrays correctly.  */
 392   if (flag_stack_arrays == -1)
 393     flag_stack_arrays = 0;
 394
 395   /* Set default.  */
 396   if (flag_max_stack_var_size == -2)
 397     flag_max_stack_var_size = 32768;
 398
 399   /* Implement -fno-automatic as -fmax-stack-var-size=0.  */
 400   if (!flag_automatic)
 401     flag_max_stack_var_size = 0;
 402
 403   /* If the user did not specify an inline matmul limit, inline up to the BLAS
 404      limit or up to 30 if no external BLAS is specified.  */
 405
 406   if (flag_inline_matmul_limit < 0)
 407     {
 408       if (flag_external_blas)
 409         flag_inline_matmul_limit = flag_blas_matmul_limit;
 410       else
 411         flag_inline_matmul_limit = 30;
 412     }
 413
 414   /* Optimization implies front end optimization, unless the user
 415      specified it directly.  */
 416
 417   if (flag_frontend_optimize == -1)
 418     flag_frontend_optimize = optimize;
 419
 420   /* Same for front end loop interchange.  */
 421
 422   if (flag_frontend_loop_interchange == -1)
 423     flag_frontend_loop_interchange = optimize;
 424
 425   if (flag_max_array_constructor < 65535)
 426     flag_max_array_constructor = 65535;
 427
 428   if (flag_fixed_line_length != 0 && flag_fixed_line_length < 7)
 429     gfc_fatal_error ("Fixed line length must be at least seven");
 430
 431   if (flag_free_line_length != 0 && flag_free_line_length < 4)
 432     gfc_fatal_error ("Free line length must be at least three");
 433
 434   if (flag_max_subrecord_length > MAX_SUBRECORD_LENGTH)
 435     gfc_fatal_error ("Maximum subrecord length cannot exceed %d",
 436                      MAX_SUBRECORD_LENGTH);
 437
 438   if (warn_return_type == -1)
 439     warn_return_type = 0;
 440
 441   gfc_cpp_post_options ();
 442
 443   if (gfc_option.allow_std & GFC_STD_F2008)
 444     lang_hooks.name = "GNU Fortran2008";
 445   else if (gfc_option.allow_std & GFC_STD_F2003)
 446     lang_hooks.name = "GNU Fortran2003";
 447
 448   return gfc_cpp_preprocess_only ();
 449 }
 450
 451
 452 static void
 453 gfc_handle_module_path_options (const char *arg)
 454 {
 455
 456   if (gfc_option.module_dir != NULL)
 457     gfc_fatal_error ("gfortran: Only one %<-J%> option allowed");
 458
 459   gfc_option.module_dir = XCNEWVEC (char, strlen (arg) + 2);
 460   strcpy (gfc_option.module_dir, arg);
 461
 462   gfc_add_include_path (gfc_option.module_dir, true, false, true);
 463
 464   strcat (gfc_option.module_dir, "/");
 465 }
 466
 467
 468 /* Handle options -ffpe-trap= and -ffpe-summary=.  */
 469
 470 static void
 471 gfc_handle_fpe_option (const char *arg, bool trap)
 472 {
 473   int result, pos = 0, n;
 474   /* precision is a backwards compatibility alias for inexact.  */
 475   static const char * const exception[] = { "invalid", "denormal", "zero",
 476                                             "overflow", "underflow",
 477                                             "inexact", "precision", NULL };
 478   static const int opt_exception[] = { GFC_FPE_INVALID, GFC_FPE_DENORMAL,
 479                                        GFC_FPE_ZERO, GFC_FPE_OVERFLOW,
 480                                        GFC_FPE_UNDERFLOW, GFC_FPE_INEXACT,
 481                                        GFC_FPE_INEXACT,
 482                                        0 };
 483
 484   /* As the default for -ffpe-summary= is nonzero, set it to 0.  */
 485   if (!trap)
 486     gfc_option.fpe_summary = 0;
 487
 488   while (*arg)
 489     {
 490       while (*arg == ',')
 491         arg++;
 492
 493       while (arg[pos] && arg[pos] != ',')
 494         pos++;
 495
 496       result = 0;
 497       if (!trap && strncmp ("none", arg, pos) == 0)
 498         {
 499           gfc_option.fpe_summary = 0;
 500           arg += pos;
 501           pos = 0;
 502           continue;
 503         }
 504       else if (!trap && strncmp ("all", arg, pos) == 0)
 505         {
 506           gfc_option.fpe_summary = GFC_FPE_INVALID | GFC_FPE_DENORMAL
 507                                    | GFC_FPE_ZERO | GFC_FPE_OVERFLOW
 508                                    | GFC_FPE_UNDERFLOW | GFC_FPE_INEXACT;
 509           arg += pos;
 510           pos = 0;
 511           continue;
 512         }
 513       else
 514         for (n = 0; exception[n] != NULL; n++)
 515           {
 516           if (exception[n] && strncmp (exception[n], arg, pos) == 0)
 517             {
 518               if (trap)
 519                 gfc_option.fpe |= opt_exception[n];
 520               else
 521                 gfc_option.fpe_summary |= opt_exception[n];
 522               arg += pos;
 523               pos = 0;
 524               result = 1;
 525               break;
 526             }
 527           }
 528       if (!result && !trap)
 529         gfc_fatal_error ("Argument to %<-ffpe-trap%> is not valid: %s", arg);
 530       else if (!result)
 531         gfc_fatal_error ("Argument to %<-ffpe-summary%> is not valid: %s", arg);
 532
 533     }
 534 }
 535
 536
 537 static void
 538 gfc_handle_runtime_check_option (const char *arg)
 539 {
 540   int result, pos = 0, n;
 541   static const char * const optname[] = { "all", "bounds", "array-temps",
 542                                           "recursion", "do", "pointer",
 543                                           "mem", NULL };
 544   static const int optmask[] = { GFC_RTCHECK_ALL, GFC_RTCHECK_BOUNDS,
 545                                  GFC_RTCHECK_ARRAY_TEMPS,
 546                                  GFC_RTCHECK_RECURSION, GFC_RTCHECK_DO,
 547                                  GFC_RTCHECK_POINTER, GFC_RTCHECK_MEM,
 548                                  0 };
 549
 550   while (*arg)
 551     {
 552       while (*arg == ',')
 553         arg++;
 554
 555       while (arg[pos] && arg[pos] != ',')
 556         pos++;
 557
 558       result = 0;
 559       for (n = 0; optname[n] != NULL; n++)
 560         {
 561           if (optname[n] && strncmp (optname[n], arg, pos) == 0)
 562             {
 563               gfc_option.rtcheck |= optmask[n];
 564               arg += pos;
 565               pos = 0;
 566               result = 1;
 567               break;
 568             }
 569           else if (optname[n] && pos > 3 && strncmp ("no-", arg, 3) == 0
 570                    && strncmp (optname[n], arg+3, pos-3) == 0)
 571             {
 572               gfc_option.rtcheck &= ~optmask[n];
 573               arg += pos;
 574               pos = 0;
 575               result = 1;
 576               break;
 577             }
 578         }
 579       if (!result)
 580         gfc_fatal_error ("Argument to %<-fcheck%> is not valid: %s", arg);
 581     }
 582 }
 583
 584
 585 /* Handle command-line options.  Returns 0 if unrecognized, 1 if
 586    recognized and handled.  */
 587
 588 bool
 589 gfc_handle_option (size_t scode, const char *arg, int value,
 590                    int kind ATTRIBUTE_UNUSED, location_t loc ATTRIBUTE_UNUSED,
 591                    const struct cl_option_handlers *handlers ATTRIBUTE_UNUSED)
 592 {
 593   bool result = true;
 594   enum opt_code code = (enum opt_code) scode;
 595
 596   if (gfc_cpp_handle_option (scode, arg, value) == 1)
 597     return true;
 598
 599   switch (code)
 600     {
 601     default:
 602       if (cl_options[code].flags & gfc_option_lang_mask ())
 603         break;
 604       result = false;
 605       break;
 606
 607     case OPT_fcheck_array_temporaries:
 608       gfc_option.rtcheck |= GFC_RTCHECK_ARRAY_TEMPS;
 609       break;
 610
 611     case OPT_fd_lines_as_code:
 612       gfc_option.flag_d_lines = 1;
 613       break;
 614
 615     case OPT_fd_lines_as_comments:
 616       gfc_option.flag_d_lines = 0;
 617       break;
 618
 619     case OPT_ffixed_form:
 620       gfc_option.source_form = FORM_FIXED;
 621       break;
 622
 623     case OPT_ffree_form:
 624       gfc_option.source_form = FORM_FREE;
 625       break;
 626
 627     case OPT_static_libgfortran:
 628 #ifndef HAVE_LD_STATIC_DYNAMIC
 629       gfc_fatal_error ("%<-static-libgfortran%> is not supported in this "
 630                        "configuration");
 631 #endif
 632       break;
 633
 634     case OPT_fintrinsic_modules_path:
 635     case OPT_fintrinsic_modules_path_:
 636
 637       /* This is needed because omp_lib.h is in a directory together
 638          with intrinsic modules.  Do no warn because during testing
 639          without an installed compiler, we would get lots of bogus
 640          warnings for a missing include directory.  */
 641       gfc_add_include_path (arg, false, false, false);
 642
 643       gfc_add_intrinsic_modules_path (arg);
 644       break;
 645
 646     case OPT_fpreprocessed:
 647       gfc_option.flag_preprocessed = value;
 648       break;
 649
 650     case OPT_fmax_identifier_length_:
 651       if (value > GFC_MAX_SYMBOL_LEN)
 652         gfc_fatal_error ("Maximum supported identifier length is %d",
 653                          GFC_MAX_SYMBOL_LEN);
 654       gfc_option.max_identifier_length = value;
 655       break;
 656
 657     case OPT_finit_local_zero:
 658       gfc_option.flag_init_integer = GFC_INIT_INTEGER_ON;
 659       gfc_option.flag_init_integer_value = 0;
 660       flag_init_real = GFC_INIT_REAL_ZERO;
 661       gfc_option.flag_init_logical = GFC_INIT_LOGICAL_FALSE;
 662       gfc_option.flag_init_character = GFC_INIT_CHARACTER_ON;
 663       gfc_option.flag_init_character_value = (char)0;
 664       break;
 665
 666     case OPT_finit_logical_:
 667       if (!strcasecmp (arg, "false"))
 668         gfc_option.flag_init_logical = GFC_INIT_LOGICAL_FALSE;
 669       else if (!strcasecmp (arg, "true"))
 670         gfc_option.flag_init_logical = GFC_INIT_LOGICAL_TRUE;
 671       else
 672         gfc_fatal_error ("Unrecognized option to %<-finit-logical%>: %s",
 673                          arg);
 674       break;
 675
 676     case OPT_finit_integer_:
 677       gfc_option.flag_init_integer = GFC_INIT_INTEGER_ON;
 678       gfc_option.flag_init_integer_value = atoi (arg);
 679       break;
 680
 681     case OPT_finit_character_:
 682       if (value >= 0 && value <= 127)
 683         {
 684           gfc_option.flag_init_character = GFC_INIT_CHARACTER_ON;
 685           gfc_option.flag_init_character_value = (char)value;
 686         }
 687       else
 688         gfc_fatal_error ("The value of n in %<-finit-character=n%> must be "
 689                          "between 0 and 127");
 690       break;
 691
 692     case OPT_I:
 693       gfc_add_include_path (arg, true, false, true);
 694       break;
 695
 696     case OPT_J:
 697       gfc_handle_module_path_options (arg);
 698       break;
 699
 700     case OPT_ffpe_trap_:
 701       gfc_handle_fpe_option (arg, true);
 702       break;
 703
 704     case OPT_ffpe_summary_:
 705       gfc_handle_fpe_option (arg, false);
 706       break;
 707
 708     case OPT_std_f95:
 709       gfc_option.allow_std = GFC_STD_F95_OBS | GFC_STD_F95 | GFC_STD_F77
 710                              | GFC_STD_F2008_OBS;
 711       gfc_option.warn_std = GFC_STD_F95_OBS;
 712       gfc_option.max_continue_fixed = 19;
 713       gfc_option.max_continue_free = 39;
 714       gfc_option.max_identifier_length = 31;
 715       warn_ampersand = 1;
 716       warn_tabs = 1;
 717       break;
 718
 719     case OPT_std_f2003:
 720       gfc_option.allow_std = GFC_STD_F95_OBS | GFC_STD_F77
 721         | GFC_STD_F2003 | GFC_STD_F95 | GFC_STD_F2008_OBS;
 722       gfc_option.warn_std = GFC_STD_F95_OBS;
 723       gfc_option.max_identifier_length = 63;
 724       warn_ampersand = 1;
 725       warn_tabs = 1;
 726       break;
 727
 728     case OPT_std_f2008:
 729       gfc_option.allow_std = GFC_STD_F95_OBS | GFC_STD_F77
 730         | GFC_STD_F2003 | GFC_STD_F95 | GFC_STD_F2008 | GFC_STD_F2008_OBS;
 731       gfc_option.warn_std = GFC_STD_F95_OBS | GFC_STD_F2008_OBS;
 732       gfc_option.max_identifier_length = 63;
 733       warn_ampersand = 1;
 734       warn_tabs = 1;
 735       break;
 736
 737     case OPT_std_f2008ts:
 738       gfc_option.allow_std = GFC_STD_F95_OBS | GFC_STD_F77
 739         | GFC_STD_F2003 | GFC_STD_F95 | GFC_STD_F2008 | GFC_STD_F2008_OBS
 740         | GFC_STD_F2008_TS;
 741       gfc_option.warn_std = GFC_STD_F95_OBS | GFC_STD_F2008_OBS;
 742       gfc_option.max_identifier_length = 63;
 743       warn_ampersand = 1;
 744       warn_tabs = 1;
 745       break;
 746
 747     case OPT_std_gnu:
 748       set_default_std_flags ();
 749       break;
 750
 751     case OPT_std_legacy:
 752       set_default_std_flags ();
 753       gfc_option.warn_std = 0;
 754       break;
 755
 756     case OPT_fshort_enums:
 757       /* Handled in language-independent code.  */
 758       break;
 759
 760     case OPT_fcheck_:
 761       gfc_handle_runtime_check_option (arg);
 762       break;
 763
 764     case OPT_fdec:
 765       /* Enable all DEC extensions.  */
 766       set_dec_flags (1);
 767       break;
 768
 769     case OPT_fdec_structure:
 770       flag_dec_structure = 1;
 771       break;
 772     }
 773
 774   Fortran_handle_option_auto (&global_options, &global_options_set,
 775                               scode, arg, value,
 776                               gfc_option_lang_mask (), kind,
 777                               loc, handlers, global_dc);
 778   return result;
 779 }
 780
 781
 782 /* Return a string with the options passed to the compiler; used for
 783    Fortran's compiler_options() intrinsic.  */
 784
 785 char *
 786 gfc_get_option_string (void)
 787 {
 788   unsigned j;
 789   size_t len, pos;
 790   char *result;
 791
 792   /* Allocate and return a one-character string with '\0'.  */
 793   if (!save_decoded_options_count)
 794     return XCNEWVEC (char, 1);
 795
 796   /* Determine required string length.  */
 797
 798   len = 0;
 799   for (j = 1; j < save_decoded_options_count; j++)
 800     {
 801       switch (save_decoded_options[j].opt_index)
 802         {
 803         case OPT_o:
 804         case OPT_d:
 805         case OPT_dumpbase:
 806         case OPT_dumpdir:
 807         case OPT_auxbase:
 808         case OPT_quiet:
 809         case OPT_version:
 810         case OPT_fintrinsic_modules_path:
 811         case OPT_fintrinsic_modules_path_:
 812           /* Ignore these.  */
 813           break;
 814         default:
 815           /* Ignore file names.  */
 816           if (save_decoded_options[j].orig_option_with_args_text[0] == '-')
 817             len += 1
 818                  + strlen (save_decoded_options[j].orig_option_with_args_text);
 819         }
 820     }
 821
 822   result = XCNEWVEC (char, len);
 823
 824   pos = 0;
 825   for (j = 1; j < save_decoded_options_count; j++)
 826     {
 827       switch (save_decoded_options[j].opt_index)
 828         {
 829         case OPT_o:
 830         case OPT_d:
 831         case OPT_dumpbase:
 832         case OPT_dumpdir:
 833         case OPT_auxbase:
 834         case OPT_quiet:
 835         case OPT_version:
 836         case OPT_fintrinsic_modules_path:
 837         case OPT_fintrinsic_modules_path_:
 838           /* Ignore these.  */
 839           continue;
 840
 841         case OPT_cpp_:
 842           /* Use "-cpp" rather than "-cpp=<temporary file>".  */
 843           len = 4;
 844           break;
 845
 846         default:
 847           /* Ignore file names.  */
 848           if (save_decoded_options[j].orig_option_with_args_text[0] != '-')
 849             continue;
 850
 851           len = strlen (save_decoded_options[j].orig_option_with_args_text);
 852         }
 853
 854       memcpy (&result[pos], save_decoded_options[j].orig_option_with_args_text, len);
 855       pos += len;
 856       result[pos++] = ' ';
 857     }
 858
 859   result[--pos] = '\0';
 860   return result;
 861 }