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) 2002-2015 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 "diagnostic.h"
  25 #include "opts.h"
  26 #include "options.h"
  27 #include "flags.h"
  28 #include "alias.h"
  29 #include "backend.h"
  30 #include "tree.h"
  31 #include "gimple.h"
  32 #include "rtl.h"
  33 #include "fold-const.h"
  34 #include "internal-fn.h"
  35 #include "langhooks.h"
  36 #include "dbgcnt.h"
  37 #include "debug.h"
  38 #include "cgraph.h"
  39 #include "target.h"
  40 #include "output.h"
  41 #include "plugin.h"
  42 #include "toplev.h"
  43 #include "tree-pass.h"
  44 #include "context.h"
  45 #include "asan.h"
  46
  47 typedef const char *const_char_p; /* For DEF_VEC_P.  */
  48
  49 static vec<const_char_p> ignored_options;
  50
  51 /* Input file names.  */
  52 const char **in_fnames;
  53 unsigned num_in_fnames;
  54
  55 /* Return a malloced slash-separated list of languages in MASK.  */
  56
  57 static char *
  58 write_langs (unsigned int mask)
  59 {
  60   unsigned int n = 0, len = 0;
  61   const char *lang_name;
  62   char *result;
  63
  64   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  65     if (mask & (1U << n))
  66       len += strlen (lang_name) + 1;
  67
  68   result = XNEWVEC (char, len);
  69   len = 0;
  70   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  71     if (mask & (1U << n))
  72       {
  73         if (len)
  74           result[len++] = '/';
  75         strcpy (result + len, lang_name);
  76         len += strlen (lang_name);
  77       }
  78
  79   result[len] = 0;
  80
  81   return result;
  82 }
  83
  84 /* Complain that switch DECODED does not apply to this front end (mask
  85    LANG_MASK).  */
  86
  87 static void
  88 complain_wrong_lang (const struct cl_decoded_option *decoded,
  89                      unsigned int lang_mask)
  90 {
  91   const struct cl_option *option = &cl_options[decoded->opt_index];
  92   const char *text = decoded->orig_option_with_args_text;
  93   char *ok_langs = NULL, *bad_lang = NULL;
  94   unsigned int opt_flags = option->flags;
  95
  96   if (!lang_hooks.complain_wrong_lang_p (option))
  97     return;
  98
  99   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
 100   if (opt_flags != CL_DRIVER)
 101     ok_langs = write_langs (opt_flags);
 102   if (lang_mask != CL_DRIVER)
 103     bad_lang = write_langs (lang_mask);
 104
 105   if (opt_flags == CL_DRIVER)
 106     error ("command line option %qs is valid for the driver but not for %s",
 107            text, bad_lang);
 108   else if (lang_mask == CL_DRIVER)
 109     gcc_unreachable ();
 110   else
 111     /* Eventually this should become a hard error IMO.  */
 112     warning (0, "command line option %qs is valid for %s but not for %s",
 113              text, ok_langs, bad_lang);
 114
 115   free (ok_langs);
 116   free (bad_lang);
 117 }
 118
 119 /* Buffer the unknown option described by the string OPT.  Currently,
 120    we only complain about unknown -Wno-* options if they may have
 121    prevented a diagnostic. Otherwise, we just ignore them.  Note that
 122    if we do complain, it is only as a warning, not an error; passing
 123    the compiler an unrecognized -Wno-* option should never change
 124    whether the compilation succeeds or fails.  */
 125
 126 static void
 127 postpone_unknown_option_warning (const char *opt)
 128 {
 129   ignored_options.safe_push (opt);
 130 }
 131
 132 /* Produce a warning for each option previously buffered.  */
 133
 134 void
 135 print_ignored_options (void)
 136 {
 137   while (!ignored_options.is_empty ())
 138     {
 139       const char *opt;
 140
 141       opt = ignored_options.pop ();
 142       warning_at (UNKNOWN_LOCATION, 0,
 143                   "unrecognized command line option %qs", opt);
 144     }
 145 }
 146
 147 /* Handle an unknown option DECODED, returning true if an error should
 148    be given.  */
 149
 150 static bool
 151 unknown_option_callback (const struct cl_decoded_option *decoded)
 152 {
 153   const char *opt = decoded->arg;
 154
 155   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
 156       && !(decoded->errors & CL_ERR_NEGATIVE))
 157     {
 158       /* We don't generate warnings for unknown -Wno-* options unless
 159          we issue diagnostics.  */
 160       postpone_unknown_option_warning (opt);
 161       return false;
 162     }
 163   else
 164     return true;
 165 }
 166
 167 /* Handle a front-end option; arguments and return value as for
 168    handle_option.  */
 169
 170 static bool
 171 lang_handle_option (struct gcc_options *opts,
 172                     struct gcc_options *opts_set,
 173                     const struct cl_decoded_option *decoded,
 174                     unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
 175                     location_t loc,
 176                     const struct cl_option_handlers *handlers,
 177                     diagnostic_context *dc)
 178 {
 179   gcc_assert (opts == &global_options);
 180   gcc_assert (opts_set == &global_options_set);
 181   gcc_assert (dc == global_dc);
 182   gcc_assert (decoded->canonical_option_num_elements <= 2);
 183   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
 184                                    decoded->value, kind, loc, handlers);
 185 }
 186
 187 /* Handle FILENAME from the command line.  */
 188
 189 static void
 190 add_input_filename (const char *filename)
 191 {
 192   num_in_fnames++;
 193   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
 194   in_fnames[num_in_fnames - 1] = filename;
 195 }
 196
 197 /* Handle the vector of command line options (located at LOC), storing
 198    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
 199    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
 200    contains has a single bit set representing the current language.
 201    HANDLERS describes what functions to call for the options.  */
 202
 203 static void
 204 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
 205                       struct cl_decoded_option *decoded_options,
 206                       unsigned int decoded_options_count,
 207                       location_t loc,
 208                       unsigned int lang_mask,
 209                       const struct cl_option_handlers *handlers,
 210                       diagnostic_context *dc)
 211 {
 212   unsigned int i;
 213
 214   for (i = 1; i < decoded_options_count; i++)
 215     {
 216       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
 217         {
 218           /* Input files should only ever appear on the main command
 219              line.  */
 220           gcc_assert (opts == &global_options);
 221           gcc_assert (opts_set == &global_options_set);
 222
 223           if (opts->x_main_input_filename == NULL)
 224             {
 225               opts->x_main_input_filename = decoded_options[i].arg;
 226               opts->x_main_input_baselength
 227                 = base_of_path (opts->x_main_input_filename,
 228                                 &opts->x_main_input_basename);
 229             }
 230           add_input_filename (decoded_options[i].arg);
 231           continue;
 232         }
 233
 234       read_cmdline_option (opts, opts_set,
 235                            decoded_options + i, loc, lang_mask, handlers,
 236                            dc);
 237     }
 238 }
 239
 240 /* Language mask determined at initialization.  */
 241 static unsigned int initial_lang_mask;
 242
 243 /* Initialize global options-related settings at start-up.  */
 244
 245 void
 246 init_options_once (void)
 247 {
 248   /* Perform language-specific options initialization.  */
 249   initial_lang_mask = lang_hooks.option_lang_mask ();
 250
 251   lang_hooks.initialize_diagnostics (global_dc);
 252   /* ??? Ideally, we should do this earlier and the FEs will override
 253      it if desired (none do it so far).  However, the way the FEs
 254      construct their pretty-printers means that all previous settings
 255      are overriden.  */
 256   diagnostic_color_init (global_dc);
 257 }
 258
 259 /* Decode command-line options to an array, like
 260    decode_cmdline_options_to_array and with the same arguments but
 261    using the default lang_mask.  */
 262
 263 void
 264 decode_cmdline_options_to_array_default_mask (unsigned int argc,
 265                                               const char **argv,
 266                                               struct cl_decoded_option **decoded_options,
 267                                               unsigned int *decoded_options_count)
 268 {
 269   decode_cmdline_options_to_array (argc, argv,
 270                                    initial_lang_mask | CL_COMMON | CL_TARGET,
 271                                    decoded_options, decoded_options_count);
 272 }
 273
 274 /* Set *HANDLERS to the default set of option handlers for use in the
 275    compilers proper (not the driver).  */
 276 void
 277 set_default_handlers (struct cl_option_handlers *handlers)
 278 {
 279   handlers->unknown_option_callback = unknown_option_callback;
 280   handlers->wrong_lang_callback = complain_wrong_lang;
 281   handlers->num_handlers = 3;
 282   handlers->handlers[0].handler = lang_handle_option;
 283   handlers->handlers[0].mask = initial_lang_mask;
 284   handlers->handlers[1].handler = common_handle_option;
 285   handlers->handlers[1].mask = CL_COMMON;
 286   handlers->handlers[2].handler = target_handle_option;
 287   handlers->handlers[2].mask = CL_TARGET;
 288 }
 289
 290 /* Parse command line options and set default flag values.  Do minimal
 291    options processing.  The decoded options are in *DECODED_OPTIONS
 292    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
 293    the options are located at LOC.  */
 294 void
 295 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
 296                 struct cl_decoded_option *decoded_options,
 297                 unsigned int decoded_options_count,
 298                 location_t loc, diagnostic_context *dc)
 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);
 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
 320 /* Process common options that have been deferred until after the
 321    handlers have been called for all options.  */
 322
 323 void
 324 handle_common_deferred_options (void)
 325 {
 326   unsigned int i;
 327   cl_deferred_option *opt;
 328   vec<cl_deferred_option> v;
 329
 330   if (common_deferred_options)
 331     v = *((vec<cl_deferred_option> *) common_deferred_options);
 332   else
 333     v = vNULL;
 334
 335   if (flag_dump_all_passed)
 336     enable_rtl_dump_file ();
 337
 338   if (flag_opt_info)
 339     opt_info_switch_p (NULL);
 340
 341   FOR_EACH_VEC_ELT (v, i, opt)
 342     {
 343       switch (opt->opt_index)
 344         {
 345         case OPT_fcall_used_:
 346           fix_register (opt->arg, 0, 1);
 347           break;
 348
 349         case OPT_fcall_saved_:
 350           fix_register (opt->arg, 0, 0);
 351           break;
 352
 353         case OPT_fdbg_cnt_:
 354           dbg_cnt_process_opt (opt->arg);
 355           break;
 356
 357         case OPT_fdbg_cnt_list:
 358           dbg_cnt_list_all_counters ();
 359           break;
 360
 361         case OPT_fdebug_prefix_map_:
 362           add_debug_prefix_map (opt->arg);
 363           break;
 364
 365         case OPT_fdump_:
 366           if (!g->get_dumps ()->dump_switch_p (opt->arg))
 367             error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
 368           break;
 369
 370         case OPT_fopt_info_:
 371           if (!opt_info_switch_p (opt->arg))
 372             error ("unrecognized command line option %<-fopt-info-%s%>",
 373                    opt->arg);
 374           break;
 375
 376         case OPT_fenable_:
 377         case OPT_fdisable_:
 378           if (opt->opt_index == OPT_fenable_)
 379             enable_pass (opt->arg);
 380           else
 381             disable_pass (opt->arg);
 382           break;
 383
 384         case OPT_ffixed_:
 385           /* Deferred.  */
 386           fix_register (opt->arg, 1, 1);
 387           break;
 388
 389         case OPT_fplugin_:
 390 #ifdef ENABLE_PLUGIN
 391           add_new_plugin (opt->arg);
 392 #else
 393           error ("plugin support is disabled; configure with --enable-plugin");
 394 #endif
 395           break;
 396
 397         case OPT_fplugin_arg_:
 398 #ifdef ENABLE_PLUGIN
 399           parse_plugin_arg_opt (opt->arg);
 400 #else
 401           error ("plugin support is disabled; configure with --enable-plugin");
 402 #endif
 403           break;
 404
 405         case OPT_frandom_seed:
 406           /* The real switch is -fno-random-seed.  */
 407           if (!opt->value)
 408             set_random_seed (NULL);
 409           break;
 410
 411         case OPT_frandom_seed_:
 412           set_random_seed (opt->arg);
 413           break;
 414
 415         case OPT_fstack_limit:
 416           /* The real switch is -fno-stack-limit.  */
 417           if (!opt->value)
 418             stack_limit_rtx = NULL_RTX;
 419           break;
 420
 421         case OPT_fstack_limit_register_:
 422           {
 423             int reg = decode_reg_name (opt->arg);
 424             if (reg < 0)
 425               error ("unrecognized register name %qs", opt->arg);
 426             else
 427               stack_limit_rtx = gen_rtx_REG (Pmode, reg);
 428           }
 429           break;
 430
 431         case OPT_fstack_limit_symbol_:
 432           stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (opt->arg));
 433           break;
 434
 435         case OPT_fasan_shadow_offset_:
 436           if (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS))
 437             error ("-fasan-shadow-offset should only be used "
 438                    "with -fsanitize=kernel-address");
 439           if (!set_asan_shadow_offset (opt->arg))
 440              error ("unrecognized shadow offset %qs", opt->arg);
 441           break;
 442
 443         case OPT_fsanitize_sections_:
 444           set_sanitized_sections (opt->arg);
 445           break;
 446
 447         default:
 448           gcc_unreachable ();
 449         }
 450     }
 451 }