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, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   4    Free Software Foundation, Inc.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "diagnostic.h"
  26 #include "opts.h"
  27 #include "flags.h"
  28 #include "ggc.h"
  29 #include "tree.h" /* Required by langhooks.h.  */
  30 #include "langhooks.h"
  31 #include "tm.h" /* Required by rtl.h.  */
  32 #include "rtl.h"
  33 #include "lto-streamer.h"
  34 #include "output.h"
  35 #include "plugin.h"
  36 #include "toplev.h"
  37 #include "tree-pass.h"
  38
  39 typedef const char *const_char_p; /* For DEF_VEC_P.  */
  40 DEF_VEC_P(const_char_p);
  41 DEF_VEC_ALLOC_P(const_char_p,heap);
  42
  43 static VEC(const_char_p,heap) *ignored_options;
  44
  45 /* Input file names.  */
  46 const char **in_fnames;
  47 unsigned num_in_fnames;
  48
  49 /* Return a malloced slash-separated list of languages in MASK.  */
  50
  51 static char *
  52 write_langs (unsigned int mask)
  53 {
  54   unsigned int n = 0, len = 0;
  55   const char *lang_name;
  56   char *result;
  57
  58   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  59     if (mask & (1U << n))
  60       len += strlen (lang_name) + 1;
  61
  62   result = XNEWVEC (char, len);
  63   len = 0;
  64   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  65     if (mask & (1U << n))
  66       {
  67         if (len)
  68           result[len++] = '/';
  69         strcpy (result + len, lang_name);
  70         len += strlen (lang_name);
  71       }
  72
  73   result[len] = 0;
  74
  75   return result;
  76 }
  77
  78 /* Complain that switch DECODED does not apply to this front end (mask
  79    LANG_MASK).  */
  80
  81 static void
  82 complain_wrong_lang (const struct cl_decoded_option *decoded,
  83                      unsigned int lang_mask)
  84 {
  85   const struct cl_option *option = &cl_options[decoded->opt_index];
  86   const char *text = decoded->orig_option_with_args_text;
  87   char *ok_langs = NULL, *bad_lang = NULL;
  88   unsigned int opt_flags = option->flags;
  89
  90   if (!lang_hooks.complain_wrong_lang_p (option))
  91     return;
  92
  93   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
  94   if (opt_flags != CL_DRIVER)
  95     ok_langs = write_langs (opt_flags);
  96   if (lang_mask != CL_DRIVER)
  97     bad_lang = write_langs (lang_mask);
  98
  99   if (opt_flags == CL_DRIVER)
 100     error ("command line option %qs is valid for the driver but not for %s",
 101            text, bad_lang);
 102   else if (lang_mask == CL_DRIVER)
 103     gcc_unreachable ();
 104   else
 105     /* Eventually this should become a hard error IMO.  */
 106     warning (0, "command line option %qs is valid for %s but not for %s",
 107              text, ok_langs, bad_lang);
 108
 109   free (ok_langs);
 110   free (bad_lang);
 111 }
 112
 113 /* Buffer the unknown option described by the string OPT.  Currently,
 114    we only complain about unknown -Wno-* options if they may have
 115    prevented a diagnostic. Otherwise, we just ignore them.  Note that
 116    if we do complain, it is only as a warning, not an error; passing
 117    the compiler an unrecognised -Wno-* option should never change
 118    whether the compilation succeeds or fails.  */
 119
 120 static void
 121 postpone_unknown_option_warning (const char *opt)
 122 {
 123   VEC_safe_push (const_char_p, heap, ignored_options, opt);
 124 }
 125
 126 /* Produce a warning for each option previously buffered.  */
 127
 128 void
 129 print_ignored_options (void)
 130 {
 131   while (!VEC_empty (const_char_p, ignored_options))
 132     {
 133       const char *opt;
 134
 135       opt = VEC_pop (const_char_p, ignored_options);
 136       warning_at (UNKNOWN_LOCATION, 0,
 137                   "unrecognized command line option \"%s\"", opt);
 138     }
 139 }
 140
 141 /* Handle an unknown option DECODED, returning true if an error should
 142    be given.  */
 143
 144 static bool
 145 unknown_option_callback (const struct cl_decoded_option *decoded)
 146 {
 147   const char *opt = decoded->arg;
 148
 149   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
 150       && !(decoded->errors & CL_ERR_NEGATIVE))
 151     {
 152       /* We don't generate warnings for unknown -Wno-* options unless
 153          we issue diagnostics.  */
 154       postpone_unknown_option_warning (opt);
 155       return false;
 156     }
 157   else
 158     return true;
 159 }
 160
 161 /* Note that an option DECODED has been successfully handled with a
 162    handler for mask MASK.  */
 163
 164 static void
 165 post_handling_callback (const struct cl_decoded_option *decoded ATTRIBUTE_UNUSED,
 166                         unsigned int mask ATTRIBUTE_UNUSED)
 167 {
 168 #ifdef ENABLE_LTO
 169   lto_register_user_option (decoded->opt_index, decoded->arg,
 170                             decoded->value, mask);
 171 #endif
 172 }
 173
 174 /* Handle a front-end option; arguments and return value as for
 175    handle_option.  */
 176
 177 static bool
 178 lang_handle_option (struct gcc_options *opts,
 179                     struct gcc_options *opts_set,
 180                     const struct cl_decoded_option *decoded,
 181                     unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
 182                     location_t loc,
 183                     const struct cl_option_handlers *handlers,
 184                     diagnostic_context *dc)
 185 {
 186   gcc_assert (opts == &global_options);
 187   gcc_assert (opts_set == &global_options_set);
 188   gcc_assert (dc == global_dc);
 189   gcc_assert (decoded->canonical_option_num_elements <= 2);
 190   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
 191                                    decoded->value, kind, loc, handlers);
 192 }
 193
 194 /* Handle FILENAME from the command line.  */
 195
 196 static void
 197 add_input_filename (const char *filename)
 198 {
 199   num_in_fnames++;
 200   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
 201   in_fnames[num_in_fnames - 1] = filename;
 202 }
 203
 204 /* Handle the vector of command line options (located at LOC), storing
 205    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
 206    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
 207    contains has a single bit set representing the current language.
 208    HANDLERS describes what functions to call for the options.  */
 209
 210 static void
 211 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
 212                       struct cl_decoded_option *decoded_options,
 213                       unsigned int decoded_options_count,
 214                       location_t loc,
 215                       unsigned int lang_mask,
 216                       const struct cl_option_handlers *handlers,
 217                       diagnostic_context *dc)
 218 {
 219   unsigned int i;
 220
 221   for (i = 1; i < decoded_options_count; i++)
 222     {
 223       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
 224         {
 225           /* Input files should only ever appear on the main command
 226              line.  */
 227           gcc_assert (opts == &global_options);
 228           gcc_assert (opts_set == &global_options_set);
 229
 230           if (main_input_filename == NULL)
 231             {
 232               main_input_filename = decoded_options[i].arg;
 233               main_input_baselength
 234                 = base_of_path (main_input_filename, &main_input_basename);
 235             }
 236           add_input_filename (decoded_options[i].arg);
 237           continue;
 238         }
 239
 240       read_cmdline_option (opts, opts_set,
 241                            decoded_options + i, loc, lang_mask, handlers,
 242                            dc);
 243     }
 244 }
 245
 246 /* Language mask determined at initialization.  */
 247 static unsigned int initial_lang_mask;
 248
 249 /* Initialize global options-related settings at start-up.  */
 250
 251 void
 252 init_options_once (void)
 253 {
 254   /* Perform language-specific options initialization.  */
 255   initial_lang_mask = lang_hooks.option_lang_mask ();
 256
 257   lang_hooks.initialize_diagnostics (global_dc);
 258 }
 259
 260 /* Decode command-line options to an array, like
 261    decode_cmdline_options_to_array and with the same arguments but
 262    using the default lang_mask.  */
 263
 264 void
 265 decode_cmdline_options_to_array_default_mask (unsigned int argc,
 266                                               const char **argv,
 267                                               struct cl_decoded_option **decoded_options,
 268                                               unsigned int *decoded_options_count)
 269 {
 270   decode_cmdline_options_to_array (argc, argv,
 271                                    initial_lang_mask | CL_COMMON | CL_TARGET,
 272                                    decoded_options, decoded_options_count);
 273 }
 274
 275 /* Set *HANDLERS to the default set of option handlers for use in the
 276    compilers proper (not the driver).  */
 277 void
 278 set_default_handlers (struct cl_option_handlers *handlers)
 279 {
 280   handlers->unknown_option_callback = unknown_option_callback;
 281   handlers->wrong_lang_callback = complain_wrong_lang;
 282   handlers->post_handling_callback = post_handling_callback;
 283   handlers->num_handlers = 3;
 284   handlers->handlers[0].handler = lang_handle_option;
 285   handlers->handlers[0].mask = initial_lang_mask;
 286   handlers->handlers[1].handler = common_handle_option;
 287   handlers->handlers[1].mask = CL_COMMON;
 288   handlers->handlers[2].handler = target_handle_option;
 289   handlers->handlers[2].mask = CL_TARGET;
 290 }
 291
 292 /* Parse command line options and set default flag values.  Do minimal
 293    options processing.  The decoded options are in *DECODED_OPTIONS
 294    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
 295    the options are located at LOC.  */
 296 void
 297 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
 298                 struct cl_decoded_option *decoded_options,
 299                 unsigned int decoded_options_count,
 300                 location_t loc, diagnostic_context *dc)
 301 {
 302   struct cl_option_handlers handlers;
 303
 304   unsigned int lang_mask;
 305
 306   lang_mask = initial_lang_mask;
 307
 308   set_default_handlers (&handlers);
 309
 310   /* Enable -Werror=coverage-mismatch by default.  */
 311   control_warning_option (OPT_Wcoverage_mismatch, (int) DK_ERROR, true,
 312                           loc, lang_mask,
 313                           &handlers, opts, opts_set, dc);
 314
 315   default_options_optimization (opts, opts_set,
 316                                 decoded_options, decoded_options_count,
 317                                 loc, lang_mask, &handlers, dc);
 318
 319 #ifdef ENABLE_LTO
 320   /* Clear any options currently held for LTO.  */
 321   lto_clear_user_options ();
 322 #endif
 323
 324   read_cmdline_options (opts, opts_set,
 325                         decoded_options, decoded_options_count,
 326                         loc, lang_mask,
 327                         &handlers, dc);
 328
 329   finish_options (opts, opts_set);
 330 }
 331
 332 /* Process common options that have been deferred until after the
 333    handlers have been called for all options.  */
 334
 335 void
 336 handle_common_deferred_options (void)
 337 {
 338   unsigned int i;
 339   cl_deferred_option *opt;
 340   VEC(cl_deferred_option,heap) *vec
 341     = (VEC(cl_deferred_option,heap) *) common_deferred_options;
 342
 343   FOR_EACH_VEC_ELT (cl_deferred_option, vec, i, opt)
 344     {
 345       switch (opt->opt_index)
 346         {
 347         case OPT_fcall_used_:
 348           fix_register (opt->arg, 0, 1);
 349           break;
 350
 351         case OPT_fcall_saved_:
 352           fix_register (opt->arg, 0, 0);
 353           break;
 354
 355         case OPT_fdump_:
 356           if (!dump_switch_p (opt->arg))
 357             error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
 358           break;
 359
 360         case OPT_ffixed_:
 361           /* Deferred.  */
 362           fix_register (opt->arg, 1, 1);
 363           break;
 364
 365         case OPT_fplugin_:
 366 #ifdef ENABLE_PLUGIN
 367           add_new_plugin (opt->arg);
 368 #else
 369           error ("plugin support is disabled; configure with --enable-plugin");
 370 #endif
 371           break;
 372
 373         case OPT_fplugin_arg_:
 374 #ifdef ENABLE_PLUGIN
 375           parse_plugin_arg_opt (opt->arg);
 376 #else
 377           error ("plugin support is disabled; configure with --enable-plugin");
 378 #endif
 379           break;
 380
 381         case OPT_fstack_limit:
 382           /* The real switch is -fno-stack-limit.  */
 383           gcc_assert (!opt->value);
 384           stack_limit_rtx = NULL_RTX;
 385           break;
 386
 387         case OPT_fstack_limit_register_:
 388           {
 389             int reg = decode_reg_name (opt->arg);
 390             if (reg < 0)
 391               error ("unrecognized register name %qs", opt->arg);
 392             else
 393               stack_limit_rtx = gen_rtx_REG (Pmode, reg);
 394           }
 395           break;
 396
 397         case OPT_fstack_limit_symbol_:
 398           stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (opt->arg));
 399           break;
 400
 401         default:
 402           gcc_unreachable ();
 403         }
 404     }
 405 }