gcc/opts-global.c

   1 /* Command line option handling.  Code involving global state that
   2    should not be shared with the driver.
   3    Copyright (C) 2002-2017 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 "asan.h"
  39
  40 typedef const char *const_char_p; /* For DEF_VEC_P.  */
  41
  42 static vec<const_char_p> ignored_options;
  43
  44 /* Input file names.  */
  45 const char **in_fnames;
  46 unsigned num_in_fnames;
  47
  48 /* Return a malloced slash-separated list of languages in MASK.  */
  49
  50 char *
  51 write_langs (unsigned int mask)
  52 {
  53   unsigned int n = 0, len = 0;
  54   const char *lang_name;
  55   char *result;
  56
  57   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  58     if (mask & (1U << n))
  59       len += strlen (lang_name) + 1;
  60
  61   result = XNEWVEC (char, len);
  62   len = 0;
  63   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  64     if (mask & (1U << n))
  65       {
  66         if (len)
  67           result[len++] = '/';
  68         strcpy (result + len, lang_name);
  69         len += strlen (lang_name);
  70       }
  71
  72   result[len] = 0;
  73
  74   return result;
  75 }
  76
  77 /* Complain that switch DECODED does not apply to this front end (mask
  78    LANG_MASK).  */
  79
  80 static void
  81 complain_wrong_lang (const struct cl_decoded_option *decoded,
  82                      unsigned int lang_mask)
  83 {
  84   const struct cl_option *option = &cl_options[decoded->opt_index];
  85   const char *text = decoded->orig_option_with_args_text;
  86   char *ok_langs = NULL, *bad_lang = NULL;
  87   unsigned int opt_flags = option->flags;
  88
  89   if (!lang_hooks.complain_wrong_lang_p (option))
  90     return;
  91
  92   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
  93   if (opt_flags != CL_DRIVER)
  94     ok_langs = write_langs (opt_flags);
  95   if (lang_mask != CL_DRIVER)
  96     bad_lang = write_langs (lang_mask);
  97
  98   if (opt_flags == CL_DRIVER)
  99     error ("command line option %qs is valid for the driver but not for %s",
 100            text, bad_lang);
 101   else if (lang_mask == CL_DRIVER)
 102     gcc_unreachable ();
 103   else
 104     /* Eventually this should become a hard error IMO.  */
 105     warning (0, "command line option %qs is valid for %s but not for %s",
 106              text, ok_langs, bad_lang);
 107
 108   free (ok_langs);
 109   free (bad_lang);
 110 }
 111
 112 /* Buffer the unknown option described by the string OPT.  Currently,
 113    we only complain about unknown -Wno-* options if they may have
 114    prevented a diagnostic. Otherwise, we just ignore them.  Note that
 115    if we do complain, it is only as a warning, not an error; passing
 116    the compiler an unrecognized -Wno-* option should never change
 117    whether the compilation succeeds or fails.  */
 118
 119 static void
 120 postpone_unknown_option_warning (const char *opt)
 121 {
 122   ignored_options.safe_push (opt);
 123 }
 124
 125 /* Produce a warning for each option previously buffered.  */
 126
 127 void
 128 print_ignored_options (void)
 129 {
 130   while (!ignored_options.is_empty ())
 131     {
 132       const char *opt;
 133
 134       opt = ignored_options.pop ();
 135       warning_at (UNKNOWN_LOCATION, 0,
 136                   "unrecognized command line option %qs", opt);
 137     }
 138 }
 139
 140 /* Handle an unknown option DECODED, returning true if an error should
 141    be given.  */
 142
 143 static bool
 144 unknown_option_callback (const struct cl_decoded_option *decoded)
 145 {
 146   const char *opt = decoded->arg;
 147
 148   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
 149       && !(decoded->errors & CL_ERR_NEGATIVE))
 150     {
 151       /* We don't generate warnings for unknown -Wno-* options unless
 152          we issue diagnostics.  */
 153       postpone_unknown_option_warning (opt);
 154       return false;
 155     }
 156   else
 157     return true;
 158 }
 159
 160 /* Handle a front-end option; arguments and return value as for
 161    handle_option.  */
 162
 163 static bool
 164 lang_handle_option (struct gcc_options *opts,
 165                     struct gcc_options *opts_set,
 166                     const struct cl_decoded_option *decoded,
 167                     unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
 168                     location_t loc,
 169                     const struct cl_option_handlers *handlers,
 170                     diagnostic_context *dc)
 171 {
 172   gcc_assert (opts == &global_options);
 173   gcc_assert (opts_set == &global_options_set);
 174   gcc_assert (dc == global_dc);
 175   gcc_assert (decoded->canonical_option_num_elements <= 2);
 176   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
 177                                    decoded->value, kind, loc, handlers);
 178 }
 179
 180 /* Handle FILENAME from the command line.  */
 181
 182 static void
 183 add_input_filename (const char *filename)
 184 {
 185   num_in_fnames++;
 186   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
 187   in_fnames[num_in_fnames - 1] = filename;
 188 }
 189
 190 /* Handle the vector of command line options (located at LOC), storing
 191    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
 192    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
 193    contains has a single bit set representing the current language.
 194    HANDLERS describes what functions to call for the options.  */
 195
 196 static void
 197 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
 198                       struct cl_decoded_option *decoded_options,
 199                       unsigned int decoded_options_count,
 200                       location_t loc,
 201                       unsigned int lang_mask,
 202                       const struct cl_option_handlers *handlers,
 203                       diagnostic_context *dc)
 204 {
 205   unsigned int i;
 206
 207   for (i = 1; i < decoded_options_count; i++)
 208     {
 209       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
 210         {
 211           /* Input files should only ever appear on the main command
 212              line.  */
 213           gcc_assert (opts == &global_options);
 214           gcc_assert (opts_set == &global_options_set);
 215
 216           if (opts->x_main_input_filename == NULL)
 217             {
 218               opts->x_main_input_filename = decoded_options[i].arg;
 219               opts->x_main_input_baselength
 220                 = base_of_path (opts->x_main_input_filename,
 221                                 &opts->x_main_input_basename);
 222             }
 223           add_input_filename (decoded_options[i].arg);
 224           continue;
 225         }
 226
 227       read_cmdline_option (opts, opts_set,
 228                            decoded_options + i, loc, lang_mask, handlers,
 229                            dc);
 230     }
 231 }
 232
 233 /* Language mask determined at initialization.  */
 234 static unsigned int initial_lang_mask;
 235
 236 /* Initialize global options-related settings at start-up.  */
 237
 238 void
 239 init_options_once (void)
 240 {
 241   /* Perform language-specific options initialization.  */
 242   initial_lang_mask = lang_hooks.option_lang_mask ();
 243
 244   lang_hooks.initialize_diagnostics (global_dc);
 245   /* ??? Ideally, we should do this earlier and the FEs will override
 246      it if desired (none do it so far).  However, the way the FEs
 247      construct their pretty-printers means that all previous settings
 248      are overriden.  */
 249   diagnostic_color_init (global_dc);
 250 }
 251
 252 /* Decode command-line options to an array, like
 253    decode_cmdline_options_to_array and with the same arguments but
 254    using the default lang_mask.  */
 255
 256 void
 257 decode_cmdline_options_to_array_default_mask (unsigned int argc,
 258                                               const char **argv,
 259                                               struct cl_decoded_option **decoded_options,
 260                                               unsigned int *decoded_options_count)
 261 {
 262   decode_cmdline_options_to_array (argc, argv,
 263                                    initial_lang_mask | CL_COMMON | CL_TARGET,
 264                                    decoded_options, decoded_options_count);
 265 }
 266
 267 /* Set *HANDLERS to the default set of option handlers for use in the
 268    compilers proper (not the driver).  */
 269 void
 270 set_default_handlers (struct cl_option_handlers *handlers)
 271 {
 272   handlers->unknown_option_callback = unknown_option_callback;
 273   handlers->wrong_lang_callback = complain_wrong_lang;
 274   handlers->num_handlers = 3;
 275   handlers->handlers[0].handler = lang_handle_option;
 276   handlers->handlers[0].mask = initial_lang_mask;
 277   handlers->handlers[1].handler = common_handle_option;
 278   handlers->handlers[1].mask = CL_COMMON;
 279   handlers->handlers[2].handler = target_handle_option;
 280   handlers->handlers[2].mask = CL_TARGET;
 281 }
 282
 283 /* Parse command line options and set default flag values.  Do minimal
 284    options processing.  The decoded options are in *DECODED_OPTIONS
 285    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
 286    the options are located at LOC.  */
 287 void
 288 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
 289                 struct cl_decoded_option *decoded_options,
 290                 unsigned int decoded_options_count,
 291                 location_t loc, diagnostic_context *dc)
 292 {
 293   struct cl_option_handlers handlers;
 294
 295   unsigned int lang_mask;
 296
 297   lang_mask = initial_lang_mask;
 298
 299   set_default_handlers (&handlers);
 300
 301   default_options_optimization (opts, opts_set,
 302                                 decoded_options, decoded_options_count,
 303                                 loc, lang_mask, &handlers, dc);
 304
 305   read_cmdline_options (opts, opts_set,
 306                         decoded_options, decoded_options_count,
 307                         loc, lang_mask,
 308                         &handlers, dc);
 309
 310   finish_options (opts, opts_set, loc);
 311 }
 312
 313 /* Hold command-line options associated with stack limitation.  */
 314 const char *opt_fstack_limit_symbol_arg = NULL;
 315 int opt_fstack_limit_register_no = -1;
 316
 317 /* Process common options that have been deferred until after the
 318    handlers have been called for all options.  */
 319
 320 void
 321 handle_common_deferred_options (void)
 322 {
 323   unsigned int i;
 324   cl_deferred_option *opt;
 325   vec<cl_deferred_option> v;
 326
 327   if (common_deferred_options)
 328     v = *((vec<cl_deferred_option> *) common_deferred_options);
 329   else
 330     v = vNULL;
 331
 332   if (flag_dump_all_passed)
 333     enable_rtl_dump_file ();
 334
 335   if (flag_opt_info)
 336     opt_info_switch_p (NULL);
 337
 338   FOR_EACH_VEC_ELT (v, i, opt)
 339     {
 340       switch (opt->opt_index)
 341         {
 342         case OPT_fcall_used_:
 343           fix_register (opt->arg, 0, 1);
 344           break;
 345
 346         case OPT_fcall_saved_:
 347           fix_register (opt->arg, 0, 0);
 348           break;
 349
 350         case OPT_fdbg_cnt_:
 351           dbg_cnt_process_opt (opt->arg);
 352           break;
 353
 354         case OPT_fdbg_cnt_list:
 355           dbg_cnt_list_all_counters ();
 356           break;
 357
 358         case OPT_fdebug_prefix_map_:
 359           add_debug_prefix_map (opt->arg);
 360           break;
 361
 362         case OPT_fdump_:
 363           if (!g->get_dumps ()->dump_switch_p (opt->arg))
 364             error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
 365           break;
 366
 367         case OPT_fopt_info_:
 368           if (!opt_info_switch_p (opt->arg))
 369             error ("unrecognized command line option %<-fopt-info-%s%>",
 370                    opt->arg);
 371           break;
 372
 373         case OPT_fenable_:
 374         case OPT_fdisable_:
 375           if (opt->opt_index == OPT_fenable_)
 376             enable_pass (opt->arg);
 377           else
 378             disable_pass (opt->arg);
 379           break;
 380
 381         case OPT_ffixed_:
 382           /* Deferred.  */
 383           fix_register (opt->arg, 1, 1);
 384           break;
 385
 386         case OPT_fplugin_:
 387 #ifdef ENABLE_PLUGIN
 388           add_new_plugin (opt->arg);
 389 #else
 390           error ("plugin support is disabled; configure with --enable-plugin");
 391 #endif
 392           break;
 393
 394         case OPT_fplugin_arg_:
 395 #ifdef ENABLE_PLUGIN
 396           parse_plugin_arg_opt (opt->arg);
 397 #else
 398           error ("plugin support is disabled; configure with --enable-plugin");
 399 #endif
 400           break;
 401
 402         case OPT_frandom_seed:
 403           /* The real switch is -fno-random-seed.  */
 404           if (!opt->value)
 405             set_random_seed (NULL);
 406           break;
 407
 408         case OPT_frandom_seed_:
 409           set_random_seed (opt->arg);
 410           break;
 411
 412         case OPT_fstack_limit:
 413           /* The real switch is -fno-stack-limit.  */
 414           if (!opt->value)
 415             stack_limit_rtx = NULL_RTX;
 416           break;
 417
 418         case OPT_fstack_limit_register_:
 419           {
 420             int reg = decode_reg_name (opt->arg);
 421             if (reg < 0)
 422               error ("unrecognized register name %qs", opt->arg);
 423             else
 424               {
 425                 /* Deactivate previous OPT_fstack_limit_symbol_ options.  */
 426                 opt_fstack_limit_symbol_arg = NULL;
 427                 opt_fstack_limit_register_no = reg;
 428               }
 429           }
 430           break;
 431
 432         case OPT_fstack_limit_symbol_:
 433           /* Deactivate previous OPT_fstack_limit_register_ options.  */
 434           opt_fstack_limit_register_no = -1;
 435           opt_fstack_limit_symbol_arg = opt->arg;
 436           break;
 437
 438         case OPT_fasan_shadow_offset_:
 439           if (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS))
 440             error ("-fasan-shadow-offset should only be used "
 441                    "with -fsanitize=kernel-address");
 442           if (!set_asan_shadow_offset (opt->arg))
 443              error ("unrecognized shadow offset %qs", opt->arg);
 444           break;
 445
 446         case OPT_fsanitize_sections_:
 447           set_sanitized_sections (opt->arg);
 448           break;
 449
 450         default:
 451           gcc_unreachable ();
 452         }
 453     }
 454 }