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) 2002-2019 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   result = XNEWVEC (char, len);
  65   len = 0;
  66   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  67     if (mask & (1U << n))
  68       {
  69         if (len)
  70           result[len++] = '/';
  71         strcpy (result + len, lang_name);
  72         len += strlen (lang_name);
  73       }
  74
  75   result[len] = 0;
  76
  77   return result;
  78 }
  79
  80 /* Complain that switch DECODED does not apply to this front end (mask
  81    LANG_MASK).  */
  82
  83 static void
  84 complain_wrong_lang (const struct cl_decoded_option *decoded,
  85                      unsigned int lang_mask)
  86 {
  87   const struct cl_option *option = &cl_options[decoded->opt_index];
  88   const char *text = decoded->orig_option_with_args_text;
  89   char *ok_langs = NULL, *bad_lang = NULL;
  90   unsigned int opt_flags = option->flags;
  91
  92   if (!lang_hooks.complain_wrong_lang_p (option))
  93     return;
  94
  95   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
  96   if (opt_flags != CL_DRIVER)
  97     ok_langs = write_langs (opt_flags);
  98   if (lang_mask != CL_DRIVER)
  99     bad_lang = write_langs (lang_mask);
 100
 101   if (opt_flags == CL_DRIVER)
 102     error ("command line option %qs is valid for the driver but not for %s",
 103            text, bad_lang);
 104   else if (lang_mask == CL_DRIVER)
 105     gcc_unreachable ();
 106   else
 107     /* Eventually this should become a hard error IMO.  */
 108     warning (0, "command line option %qs is valid for %s but not for %s",
 109              text, ok_langs, bad_lang);
 110
 111   free (ok_langs);
 112   free (bad_lang);
 113 }
 114
 115 /* Buffer the unknown option described by the string OPT.  Currently,
 116    we only complain about unknown -Wno-* options if they may have
 117    prevented a diagnostic. Otherwise, we just ignore them.  Note that
 118    if we do complain, it is only as a warning, not an error; passing
 119    the compiler an unrecognized -Wno-* option should never change
 120    whether the compilation succeeds or fails.  */
 121
 122 static void
 123 postpone_unknown_option_warning (const char *opt)
 124 {
 125   ignored_options.safe_push (opt);
 126 }
 127
 128 /* Produce a warning for each option previously buffered.  */
 129
 130 void
 131 print_ignored_options (void)
 132 {
 133   while (!ignored_options.is_empty ())
 134     {
 135       const char *opt;
 136
 137       opt = ignored_options.pop ();
 138       warning_at (UNKNOWN_LOCATION, 0,
 139                   "unrecognized command line option %qs", opt);
 140     }
 141 }
 142
 143 /* Handle an unknown option DECODED, returning true if an error should
 144    be given.  */
 145
 146 static bool
 147 unknown_option_callback (const struct cl_decoded_option *decoded)
 148 {
 149   const char *opt = decoded->arg;
 150
 151   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
 152       && !(decoded->errors & CL_ERR_NEGATIVE))
 153     {
 154       /* We don't generate warnings for unknown -Wno-* options unless
 155          we issue diagnostics.  */
 156       postpone_unknown_option_warning (opt);
 157       return false;
 158     }
 159   else
 160     return true;
 161 }
 162
 163 /* Handle a front-end option; arguments and return value as for
 164    handle_option.  */
 165
 166 static bool
 167 lang_handle_option (struct gcc_options *opts,
 168                     struct gcc_options *opts_set,
 169                     const struct cl_decoded_option *decoded,
 170                     unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
 171                     location_t loc,
 172                     const struct cl_option_handlers *handlers,
 173                     diagnostic_context *dc,
 174                     void (*) (void))
 175 {
 176   gcc_assert (opts == &global_options);
 177   gcc_assert (opts_set == &global_options_set);
 178   gcc_assert (dc == global_dc);
 179   gcc_assert (decoded->canonical_option_num_elements <= 2);
 180   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
 181                                    decoded->value, kind, loc, handlers);
 182 }
 183
 184 /* Handle FILENAME from the command line.  */
 185
 186 static void
 187 add_input_filename (const char *filename)
 188 {
 189   num_in_fnames++;
 190   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
 191   in_fnames[num_in_fnames - 1] = filename;
 192 }
 193
 194 /* Handle the vector of command line options (located at LOC), storing
 195    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
 196    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
 197    contains has a single bit set representing the current language.
 198    HANDLERS describes what functions to call for the options.  */
 199
 200 static void
 201 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
 202                       struct cl_decoded_option *decoded_options,
 203                       unsigned int decoded_options_count,
 204                       location_t loc,
 205                       unsigned int lang_mask,
 206                       const struct cl_option_handlers *handlers,
 207                       diagnostic_context *dc)
 208 {
 209   unsigned int i;
 210
 211   for (i = 1; i < decoded_options_count; i++)
 212     {
 213       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
 214         {
 215           /* Input files should only ever appear on the main command
 216              line.  */
 217           gcc_assert (opts == &global_options);
 218           gcc_assert (opts_set == &global_options_set);
 219
 220           if (opts->x_main_input_filename == NULL)
 221             {
 222               opts->x_main_input_filename = decoded_options[i].arg;
 223               opts->x_main_input_baselength
 224                 = base_of_path (opts->x_main_input_filename,
 225                                 &opts->x_main_input_basename);
 226             }
 227           add_input_filename (decoded_options[i].arg);
 228           continue;
 229         }
 230
 231       read_cmdline_option (opts, opts_set,
 232                            decoded_options + i, loc, lang_mask, handlers,
 233                            dc);
 234     }
 235 }
 236
 237 /* Language mask determined at initialization.  */
 238 static unsigned int initial_lang_mask;
 239
 240 /* Initialize global options-related settings at start-up.  */
 241
 242 void
 243 init_options_once (void)
 244 {
 245   /* Perform language-specific options initialization.  */
 246   initial_lang_mask = lang_hooks.option_lang_mask ();
 247
 248   lang_hooks.initialize_diagnostics (global_dc);
 249   /* ??? Ideally, we should do this earlier and the FEs will override
 250      it if desired (none do it so far).  However, the way the FEs
 251      construct their pretty-printers means that all previous settings
 252      are overriden.  */
 253   diagnostic_color_init (global_dc);
 254 }
 255
 256 /* Decode command-line options to an array, like
 257    decode_cmdline_options_to_array and with the same arguments but
 258    using the default lang_mask.  */
 259
 260 void
 261 decode_cmdline_options_to_array_default_mask (unsigned int argc,
 262                                               const char **argv,
 263                                               struct cl_decoded_option **decoded_options,
 264                                               unsigned int *decoded_options_count)
 265 {
 266   decode_cmdline_options_to_array (argc, argv,
 267                                    initial_lang_mask | CL_COMMON | CL_TARGET,
 268                                    decoded_options, decoded_options_count);
 269 }
 270
 271 /* Set *HANDLERS to the default set of option handlers for use in the
 272    compilers proper (not the driver).  */
 273 void
 274 set_default_handlers (struct cl_option_handlers *handlers,
 275                       void (*target_option_override_hook) (void))
 276 {
 277   handlers->unknown_option_callback = unknown_option_callback;
 278   handlers->wrong_lang_callback = complain_wrong_lang;
 279   handlers->target_option_override_hook = target_option_override_hook;
 280   handlers->num_handlers = 3;
 281   handlers->handlers[0].handler = lang_handle_option;
 282   handlers->handlers[0].mask = initial_lang_mask;
 283   handlers->handlers[1].handler = common_handle_option;
 284   handlers->handlers[1].mask = CL_COMMON;
 285   handlers->handlers[2].handler = target_handle_option;
 286   handlers->handlers[2].mask = CL_TARGET;
 287 }
 288
 289 /* Parse command line options and set default flag values.  Do minimal
 290    options processing.  The decoded options are in *DECODED_OPTIONS
 291    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
 292    the options are located at LOC.  */
 293 void
 294 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
 295                 struct cl_decoded_option *decoded_options,
 296                 unsigned int decoded_options_count,
 297                 location_t loc, diagnostic_context *dc,
 298                 void (*target_option_override_hook) (void))
 299 {
 300   struct cl_option_handlers handlers;
 301
 302   unsigned int lang_mask;
 303
 304   lang_mask = initial_lang_mask;
 305
 306   set_default_handlers (&handlers, target_option_override_hook);
 307
 308   default_options_optimization (opts, opts_set,
 309                                 decoded_options, decoded_options_count,
 310                                 loc, lang_mask, &handlers, dc);
 311
 312   read_cmdline_options (opts, opts_set,
 313                         decoded_options, decoded_options_count,
 314                         loc, lang_mask,
 315                         &handlers, dc);
 316
 317   finish_options (opts, opts_set, loc);
 318
 319   /* Print --help=* if used.  */
 320   if (help_option_argument != NULL)
 321     print_help (opts, lang_mask);
 322 }
 323
 324 /* Hold command-line options associated with stack limitation.  */
 325 const char *opt_fstack_limit_symbol_arg = NULL;
 326 int opt_fstack_limit_register_no = -1;
 327
 328 /* Process common options that have been deferred until after the
 329    handlers have been called for all options.  */
 330
 331 void
 332 handle_common_deferred_options (void)
 333 {
 334   unsigned int i;
 335   cl_deferred_option *opt;
 336   vec<cl_deferred_option> v;
 337
 338   if (common_deferred_options)
 339     v = *((vec<cl_deferred_option> *) common_deferred_options);
 340   else
 341     v = vNULL;
 342
 343   if (flag_dump_all_passed)
 344     enable_rtl_dump_file ();
 345
 346   if (flag_opt_info)
 347     opt_info_switch_p (NULL);
 348
 349   FOR_EACH_VEC_ELT (v, i, opt)
 350     {
 351       switch (opt->opt_index)
 352         {
 353         case OPT_fcall_used_:
 354           fix_register (opt->arg, 0, 1);
 355           break;
 356
 357         case OPT_fcall_saved_:
 358           fix_register (opt->arg, 0, 0);
 359           break;
 360
 361         case OPT_fdbg_cnt_:
 362           dbg_cnt_process_opt (opt->arg);
 363           break;
 364
 365         case OPT_fdbg_cnt_list:
 366           dbg_cnt_list_all_counters ();
 367           break;
 368
 369         case OPT_fdebug_prefix_map_:
 370           add_debug_prefix_map (opt->arg);
 371           break;
 372
 373         case OPT_ffile_prefix_map_:
 374           add_file_prefix_map (opt->arg);
 375           break;
 376
 377         case OPT_fdump_:
 378           if (!g->get_dumps ()->dump_switch_p (opt->arg))
 379             error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
 380           break;
 381
 382         case OPT_fopt_info_:
 383           if (!opt_info_switch_p (opt->arg))
 384             error ("unrecognized command line option %<-fopt-info-%s%>",
 385                    opt->arg);
 386           break;
 387
 388         case OPT_fenable_:
 389         case OPT_fdisable_:
 390           if (opt->opt_index == OPT_fenable_)
 391             enable_pass (opt->arg);
 392           else
 393             disable_pass (opt->arg);
 394           break;
 395
 396         case OPT_ffixed_:
 397           /* Deferred.  */
 398           fix_register (opt->arg, 1, 1);
 399           break;
 400
 401         case OPT_fplugin_:
 402 #ifdef ENABLE_PLUGIN
 403           add_new_plugin (opt->arg);
 404 #else
 405           error ("plugin support is disabled; configure with --enable-plugin");
 406 #endif
 407           break;
 408
 409         case OPT_fplugin_arg_:
 410 #ifdef ENABLE_PLUGIN
 411           parse_plugin_arg_opt (opt->arg);
 412 #else
 413           error ("plugin support is disabled; configure with --enable-plugin");
 414 #endif
 415           break;
 416
 417         case OPT_frandom_seed:
 418           /* The real switch is -fno-random-seed.  */
 419           if (!opt->value)
 420             set_random_seed (NULL);
 421           break;
 422
 423         case OPT_frandom_seed_:
 424           set_random_seed (opt->arg);
 425           break;
 426
 427         case OPT_fstack_limit:
 428           /* The real switch is -fno-stack-limit.  */
 429           if (!opt->value)
 430             stack_limit_rtx = NULL_RTX;
 431           break;
 432
 433         case OPT_fstack_limit_register_:
 434           {
 435             int reg = decode_reg_name (opt->arg);
 436             if (reg < 0)
 437               error ("unrecognized register name %qs", opt->arg);
 438             else
 439               {
 440                 /* Deactivate previous OPT_fstack_limit_symbol_ options.  */
 441                 opt_fstack_limit_symbol_arg = NULL;
 442                 opt_fstack_limit_register_no = reg;
 443               }
 444           }
 445           break;
 446
 447         case OPT_fstack_limit_symbol_:
 448           /* Deactivate previous OPT_fstack_limit_register_ options.  */
 449           opt_fstack_limit_register_no = -1;
 450           opt_fstack_limit_symbol_arg = opt->arg;
 451           break;
 452
 453         case OPT_fasan_shadow_offset_:
 454           if (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS))
 455             error ("%<-fasan-shadow-offset%> should only be used "
 456                    "with %<-fsanitize=kernel-address%>");
 457           if (!set_asan_shadow_offset (opt->arg))
 458              error ("unrecognized shadow offset %qs", opt->arg);
 459           break;
 460
 461         case OPT_fsanitize_sections_:
 462           set_sanitized_sections (opt->arg);
 463           break;
 464
 465         default:
 466           gcc_unreachable ();
 467         }
 468     }
 469 }