gcc/opts-global.cc

   1 /* Command line option handling.  Code involving global state that
   2    should not be shared with the driver.
   3    Copyright (C) 2002-2022 Free Software Foundation, Inc.
   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 "backend.h"
  25 #include "rtl.h"
  26 #include "tree.h"
  27 #include "tree-pass.h"
  28 #include "diagnostic.h"
  29 #include "opts.h"
  30 #include "flags.h"
  31 #include "langhooks.h"
  32 #include "dbgcnt.h"
  33 #include "debug.h"
  34 #include "output.h"
  35 #include "plugin.h"
  36 #include "toplev.h"
  37 #include "context.h"
  38 #include "stringpool.h"
  39 #include "attribs.h"
  40 #include "asan.h"
  41 #include "file-prefix-map.h" /* add_*_prefix_map()  */
  42
  43 typedef const char *const_char_p; /* For DEF_VEC_P.  */
  44
  45 static vec<const_char_p> ignored_options;
  46
  47 /* Input file names.  */
  48 const char **in_fnames;
  49 unsigned num_in_fnames;
  50
  51 /* Return a malloced slash-separated list of languages in MASK.  */
  52
  53 char *
  54 write_langs (unsigned int mask)
  55 {
  56   unsigned int n = 0, len = 0;
  57   const char *lang_name;
  58   char *result;
  59
  60   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  61     if (mask & (1U << n))
  62       len += strlen (lang_name) + 1;
  63
  64   /* Allocate at least one character as we'll terminate the string
  65      at the very end of this function.  */
  66   result = XNEWVEC (char, MAX (1, len));
  67   len = 0;
  68   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  69     if (mask & (1U << n))
  70       {
  71         if (len)
  72           result[len++] = '/';
  73         strcpy (result + len, lang_name);
  74         len += strlen (lang_name);
  75       }
  76
  77   result[len] = 0;
  78
  79   return result;
  80 }
  81
  82 /* Complain that switch DECODED does not apply to this front end (mask
  83    LANG_MASK).  */
  84
  85 static void
  86 complain_wrong_lang (const struct cl_decoded_option *decoded,
  87                      unsigned int lang_mask)
  88 {
  89   const struct cl_option *option = &cl_options[decoded->opt_index];
  90   const char *text = decoded->orig_option_with_args_text;
  91   char *ok_langs = NULL, *bad_lang = NULL;
  92   unsigned int opt_flags = option->flags;
  93
  94   if (!lang_hooks.complain_wrong_lang_p (option))
  95     return;
  96
  97   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
  98   if (opt_flags != CL_DRIVER)
  99     ok_langs = write_langs (opt_flags);
 100   if (lang_mask != CL_DRIVER)
 101     bad_lang = write_langs (lang_mask);
 102
 103   if (opt_flags == CL_DRIVER)
 104     error ("command-line option %qs is valid for the driver but not for %s",
 105            text, bad_lang);
 106   else if (lang_mask == CL_DRIVER)
 107     gcc_unreachable ();
 108   else if (ok_langs[0] != '\0')
 109     /* Eventually this should become a hard error IMO.  */
 110     warning (0, "command-line option %qs is valid for %s but not for %s",
 111              text, ok_langs, bad_lang);
 112   else
 113     /* Happens for -Werror=warning_name.  */
 114     warning (0, "%<-Werror=%> argument %qs is not valid for %s",
 115              text, bad_lang);
 116
 117   free (ok_langs);
 118   free (bad_lang);
 119 }
 120
 121 /* Buffer the unknown option described by the string OPT.  Currently,
 122    we only complain about unknown -Wno-* options if they may have
 123    prevented a diagnostic. Otherwise, we just ignore them.  Note that
 124    if we do complain, it is only as a warning, not an error; passing
 125    the compiler an unrecognized -Wno-* option should never change
 126    whether the compilation succeeds or fails.  */
 127
 128 static void
 129 postpone_unknown_option_warning (const char *opt)
 130 {
 131   ignored_options.safe_push (opt);
 132 }
 133
 134 /* Produce a warning for each option previously buffered.  */
 135
 136 void
 137 print_ignored_options (void)
 138 {
 139   while (!ignored_options.is_empty ())
 140     {
 141       const char *opt;
 142
 143       opt = ignored_options.pop ();
 144       /* Use inform, not warning_at, to avoid promoting these to errors.  */
 145       inform (UNKNOWN_LOCATION,
 146               "unrecognized command-line option %qs may have been intended "
 147               "to silence earlier diagnostics", opt);
 148     }
 149 }
 150
 151 /* Handle an unknown option DECODED, returning true if an error should
 152    be given.  */
 153
 154 static bool
 155 unknown_option_callback (const struct cl_decoded_option *decoded)
 156 {
 157   const char *opt = decoded->arg;
 158
 159   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
 160       && !(decoded->errors & CL_ERR_NEGATIVE))
 161     {
 162       /* We don't generate warnings for unknown -Wno-* options unless
 163          we issue diagnostics.  */
 164       postpone_unknown_option_warning (opt);
 165       return false;
 166     }
 167   else
 168     return true;
 169 }
 170
 171 /* Handle a front-end option; arguments and return value as for
 172    handle_option.  */
 173
 174 static bool
 175 lang_handle_option (struct gcc_options *opts,
 176                     struct gcc_options *opts_set,
 177                     const struct cl_decoded_option *decoded,
 178                     unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
 179                     location_t loc,
 180                     const struct cl_option_handlers *handlers,
 181                     diagnostic_context *dc,
 182                     void (*) (void))
 183 {
 184   gcc_assert (opts == &global_options);
 185   gcc_assert (opts_set == &global_options_set);
 186   gcc_assert (dc == global_dc);
 187   gcc_assert (decoded->canonical_option_num_elements <= 2);
 188   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
 189                                    decoded->value, kind, loc, handlers);
 190 }
 191
 192 /* Handle FILENAME from the command line.  */
 193
 194 static void
 195 add_input_filename (const char *filename)
 196 {
 197   num_in_fnames++;
 198   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
 199   in_fnames[num_in_fnames - 1] = filename;
 200 }
 201
 202 /* Handle the vector of command line options (located at LOC), storing
 203    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
 204    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
 205    contains has a single bit set representing the current language.
 206    HANDLERS describes what functions to call for the options.  */
 207
 208 static void
 209 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
 210                       struct cl_decoded_option *decoded_options,
 211                       unsigned int decoded_options_count,
 212                       location_t loc,
 213                       unsigned int lang_mask,
 214                       const struct cl_option_handlers *handlers,
 215                       diagnostic_context *dc)
 216 {
 217   unsigned int i;
 218
 219   for (i = 1; i < decoded_options_count; i++)
 220     {
 221       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
 222         {
 223           /* Input files should only ever appear on the main command
 224              line.  */
 225           gcc_assert (opts == &global_options);
 226           gcc_assert (opts_set == &global_options_set);
 227
 228           if (opts->x_main_input_filename == NULL)
 229             {
 230               opts->x_main_input_filename = decoded_options[i].arg;
 231               opts->x_main_input_baselength
 232                 = base_of_path (opts->x_main_input_filename,
 233                                 &opts->x_main_input_basename);
 234             }
 235           add_input_filename (decoded_options[i].arg);
 236           continue;
 237         }
 238
 239       read_cmdline_option (opts, opts_set,
 240                            decoded_options + i, loc, lang_mask, handlers,
 241                            dc);
 242     }
 243 }
 244
 245 /* Language mask determined at initialization.  */
 246 static unsigned int initial_lang_mask;
 247
 248 /* Initialize global options-related settings at start-up.  */
 249
 250 void
 251 init_options_once (void)
 252 {
 253   /* Perform language-specific options initialization.  */
 254   initial_lang_mask = lang_hooks.option_lang_mask ();
 255
 256   lang_hooks.initialize_diagnostics (global_dc);
 257   /* ??? Ideally, we should do this earlier and the FEs will override
 258      it if desired (none do it so far).  However, the way the FEs
 259      construct their pretty-printers means that all previous settings
 260      are overriden.  */
 261   diagnostic_color_init (global_dc);
 262   diagnostic_urls_init (global_dc);
 263 }
 264
 265 /* Decode command-line options to an array, like
 266    decode_cmdline_options_to_array and with the same arguments but
 267    using the default lang_mask.  */
 268
 269 void
 270 decode_cmdline_options_to_array_default_mask (unsigned int argc,
 271                                               const char **argv,
 272                                               struct cl_decoded_option **decoded_options,
 273                                               unsigned int *decoded_options_count)
 274 {
 275   decode_cmdline_options_to_array (argc, argv,
 276                                    initial_lang_mask | CL_COMMON | CL_TARGET,
 277                                    decoded_options, decoded_options_count);
 278 }
 279
 280 /* Set *HANDLERS to the default set of option handlers for use in the
 281    compilers proper (not the driver).  */
 282 void
 283 set_default_handlers (struct cl_option_handlers *handlers,
 284                       void (*target_option_override_hook) (void))
 285 {
 286   handlers->unknown_option_callback = unknown_option_callback;
 287   handlers->wrong_lang_callback = complain_wrong_lang;
 288   handlers->target_option_override_hook = target_option_override_hook;
 289   handlers->num_handlers = 3;
 290   handlers->handlers[0].handler = lang_handle_option;
 291   handlers->handlers[0].mask = initial_lang_mask;
 292   handlers->handlers[1].handler = common_handle_option;
 293   handlers->handlers[1].mask = CL_COMMON;
 294   handlers->handlers[2].handler = target_handle_option;
 295   handlers->handlers[2].mask = CL_TARGET;
 296 }
 297
 298 /* Parse command line options and set default flag values.  Do minimal
 299    options processing.  The decoded options are in *DECODED_OPTIONS
 300    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
 301    the options are located at LOC.  */
 302 void
 303 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
 304                 struct cl_decoded_option *decoded_options,
 305                 unsigned int decoded_options_count,
 306                 location_t loc, diagnostic_context *dc,
 307                 void (*target_option_override_hook) (void))
 308 {
 309   struct cl_option_handlers handlers;
 310
 311   unsigned int lang_mask;
 312
 313   lang_mask = initial_lang_mask;
 314
 315   set_default_handlers (&handlers, target_option_override_hook);
 316
 317   default_options_optimization (opts, opts_set,
 318                                 decoded_options, decoded_options_count,
 319                                 loc, lang_mask, &handlers, dc);
 320
 321   read_cmdline_options (opts, opts_set,
 322                         decoded_options, decoded_options_count,
 323                         loc, lang_mask,
 324                         &handlers, dc);
 325
 326   finish_options (opts, opts_set, loc);
 327
 328   /* Print --help=* if used.  */
 329   unsigned i;
 330   const char *arg;
 331
 332   if (!help_option_arguments.is_empty ())
 333     {
 334       /* Make sure --help=* sees the overridden values.  */
 335       target_option_override_hook ();
 336
 337       FOR_EACH_VEC_ELT (help_option_arguments, i, arg)
 338         print_help (opts, lang_mask, arg);
 339     }
 340 }
 341
 342 /* Hold command-line options associated with stack limitation.  */
 343 const char *opt_fstack_limit_symbol_arg = NULL;
 344 int opt_fstack_limit_register_no = -1;
 345
 346 /* Process common options that have been deferred until after the
 347    handlers have been called for all options.  */
 348
 349 void
 350 handle_common_deferred_options (void)
 351 {
 352   unsigned int i;
 353   cl_deferred_option *opt;
 354   vec<cl_deferred_option> v;
 355
 356   if (common_deferred_options)
 357     v = *((vec<cl_deferred_option> *) common_deferred_options);
 358   else
 359     v = vNULL;
 360
 361   if (flag_dump_all_passed)
 362     enable_rtl_dump_file ();
 363
 364   if (flag_opt_info)
 365     opt_info_switch_p (NULL);
 366
 367   FOR_EACH_VEC_ELT (v, i, opt)
 368     {
 369       switch (opt->opt_index)
 370         {
 371         case OPT_fcall_used_:
 372           fix_register (opt->arg, 0, 1);
 373           break;
 374
 375         case OPT_fcall_saved_:
 376           fix_register (opt->arg, 0, 0);
 377           break;
 378
 379         case OPT_fdbg_cnt_:
 380           dbg_cnt_process_opt (opt->arg);
 381           break;
 382
 383         case OPT_fdebug_prefix_map_:
 384           add_debug_prefix_map (opt->arg);
 385           break;
 386
 387         case OPT_ffile_prefix_map_:
 388           add_file_prefix_map (opt->arg);
 389           break;
 390
 391         case OPT_fprofile_prefix_map_:
 392           add_profile_prefix_map (opt->arg);
 393           break;
 394
 395         case OPT_fdump_:
 396           g->get_dumps ()->dump_switch_p (opt->arg);
 397           break;
 398
 399         case OPT_fopt_info_:
 400           if (!opt_info_switch_p (opt->arg))
 401             error ("unrecognized command-line option %<-fopt-info-%s%>",
 402                    opt->arg);
 403           break;
 404
 405         case OPT_fenable_:
 406         case OPT_fdisable_:
 407           if (opt->opt_index == OPT_fenable_)
 408             enable_pass (opt->arg);
 409           else
 410             disable_pass (opt->arg);
 411           break;
 412
 413         case OPT_ffixed_:
 414           /* Deferred.  */
 415           fix_register (opt->arg, 1, 1);
 416           break;
 417
 418         case OPT_fplugin_:
 419 #ifdef ENABLE_PLUGIN
 420           add_new_plugin (opt->arg);
 421 #else
 422           error ("plugin support is disabled; configure with "
 423                  "%<--enable-plugin%>");
 424 #endif
 425           break;
 426
 427         case OPT_fplugin_arg_:
 428 #ifdef ENABLE_PLUGIN
 429           parse_plugin_arg_opt (opt->arg);
 430 #else
 431           error ("plugin support is disabled; configure with "
 432                  "%<--enable-plugin%>");
 433 #endif
 434           break;
 435
 436         case OPT_frandom_seed:
 437           /* The real switch is -fno-random-seed.  */
 438           if (!opt->value)
 439             set_random_seed (NULL);
 440           break;
 441
 442         case OPT_frandom_seed_:
 443           set_random_seed (opt->arg);
 444           break;
 445
 446         case OPT_fstack_limit:
 447           /* The real switch is -fno-stack-limit.  */
 448           if (!opt->value)
 449             stack_limit_rtx = NULL_RTX;
 450           break;
 451
 452         case OPT_fstack_limit_register_:
 453           {
 454             int reg = decode_reg_name (opt->arg);
 455             if (reg < 0)
 456               error ("unrecognized register name %qs", opt->arg);
 457             else
 458               {
 459                 /* Deactivate previous OPT_fstack_limit_symbol_ options.  */
 460                 opt_fstack_limit_symbol_arg = NULL;
 461                 opt_fstack_limit_register_no = reg;
 462               }
 463           }
 464           break;
 465
 466         case OPT_fstack_limit_symbol_:
 467           /* Deactivate previous OPT_fstack_limit_register_ options.  */
 468           opt_fstack_limit_register_no = -1;
 469           opt_fstack_limit_symbol_arg = opt->arg;
 470           break;
 471
 472         case OPT_fasan_shadow_offset_:
 473           if (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS))
 474             error ("%<-fasan-shadow-offset%> should only be used "
 475                    "with %<-fsanitize=kernel-address%>");
 476           if (!set_asan_shadow_offset (opt->arg))
 477              error ("unrecognized shadow offset %qs", opt->arg);
 478           break;
 479
 480         case OPT_fsanitize_sections_:
 481           set_sanitized_sections (opt->arg);
 482           break;
 483
 484         default:
 485           gcc_unreachable ();
 486         }
 487     }
 488 }