gcc/diagnostic.c

   1 /* Language-independent diagnostic subroutines for the GNU Compiler Collection
   2    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
   3    Free Software Foundation, Inc.
   4    Contributed by Gabriel Dos Reis <gdr@codesourcery.com>
   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
  23 /* This file implements the language independent aspect of diagnostic
  24    message module.  */
  25
  26 #include "config.h"
  27 #undef FLOAT /* This is for hpux. They should change hpux.  */
  28 #undef FFS  /* Some systems define this in param.h.  */
  29 #include "system.h"
  30 #include "coretypes.h"
  31 #include "tm.h"
  32 #include "tree.h"
  33 #include "version.h"
  34 #include "tm_p.h"
  35 #include "flags.h"
  36 #include "input.h"
  37 #include "toplev.h"
  38 #include "intl.h"
  39 #include "diagnostic.h"
  40 #include "langhooks.h"
  41 #include "langhooks-def.h"
  42 #include "opts.h"
  43
  44
  45 /* Prototypes.  */
  46 static char *build_message_string (const char *, ...) ATTRIBUTE_PRINTF_1;
  47
  48 static void default_diagnostic_starter (diagnostic_context *,
  49                                         diagnostic_info *);
  50 static void default_diagnostic_finalizer (diagnostic_context *,
  51                                           diagnostic_info *);
  52
  53 static void error_recursion (diagnostic_context *) ATTRIBUTE_NORETURN;
  54
  55 static void diagnostic_action_after_output (diagnostic_context *,
  56                                             diagnostic_info *);
  57 static void real_abort (void) ATTRIBUTE_NORETURN;
  58
  59 /* A diagnostic_context surrogate for stderr.  */
  60 static diagnostic_context global_diagnostic_context;
  61 diagnostic_context *global_dc = &global_diagnostic_context;
  62
  63 \f
  64 /* Return a malloc'd string containing MSG formatted a la printf.  The
  65    caller is responsible for freeing the memory.  */
  66 static char *
  67 build_message_string (const char *msg, ...)
  68 {
  69   char *str;
  70   va_list ap;
  71
  72   va_start (ap, msg);
  73   vasprintf (&str, msg, ap);
  74   va_end (ap);
  75
  76   return str;
  77 }
  78
  79 /* Same as diagnostic_build_prefix, but only the source FILE is given.  */
  80 char *
  81 file_name_as_prefix (const char *f)
  82 {
  83   return build_message_string ("%s: ", f);
  84 }
  85
  86
  87 \f
  88 /* Initialize the diagnostic message outputting machinery.  */
  89 void
  90 diagnostic_initialize (diagnostic_context *context)
  91 {
  92   /* Allocate a basic pretty-printer.  Clients will replace this a
  93      much more elaborated pretty-printer if they wish.  */
  94   context->printer = XNEW (pretty_printer);
  95   pp_construct (context->printer, NULL, 0);
  96   /* By default, diagnostics are sent to stderr.  */
  97   context->printer->buffer->stream = stderr;
  98   /* By default, we emit prefixes once per message.  */
  99   context->printer->wrapping.rule = DIAGNOSTICS_SHOW_PREFIX_ONCE;
 100
 101   memset (context->diagnostic_count, 0, sizeof context->diagnostic_count);
 102   context->issue_warnings_are_errors_message = true;
 103   context->warning_as_error_requested = false;
 104   memset (context->classify_diagnostic, DK_UNSPECIFIED,
 105           sizeof context->classify_diagnostic);
 106   context->show_option_requested = false;
 107   context->abort_on_error = false;
 108   context->internal_error = NULL;
 109   diagnostic_starter (context) = default_diagnostic_starter;
 110   diagnostic_finalizer (context) = default_diagnostic_finalizer;
 111   context->last_module = 0;
 112   context->last_function = NULL;
 113   context->lock = 0;
 114 }
 115
 116 /* Initialize DIAGNOSTIC, where the message MSG has already been
 117    translated.  */
 118 void
 119 diagnostic_set_info_translated (diagnostic_info *diagnostic, const char *msg,
 120                                 va_list *args, location_t location,
 121                                 diagnostic_t kind)
 122 {
 123   diagnostic->message.err_no = errno;
 124   diagnostic->message.args_ptr = args;
 125   diagnostic->message.format_spec = msg;
 126   diagnostic->location = location;
 127   diagnostic->kind = kind;
 128   diagnostic->option_index = 0;
 129 }
 130
 131 /* Initialize DIAGNOSTIC, where the message GMSGID has not yet been
 132    translated.  */
 133 void
 134 diagnostic_set_info (diagnostic_info *diagnostic, const char *gmsgid,
 135                      va_list *args, location_t location,
 136                      diagnostic_t kind)
 137 {
 138   diagnostic_set_info_translated (diagnostic, _(gmsgid), args, location, kind);
 139 }
 140
 141 /* Return a malloc'd string describing a location.  The caller is
 142    responsible for freeing the memory.  */
 143 char *
 144 diagnostic_build_prefix (diagnostic_info *diagnostic)
 145 {
 146   static const char *const diagnostic_kind_text[] = {
 147 #define DEFINE_DIAGNOSTIC_KIND(K, T) (T),
 148 #include "diagnostic.def"
 149 #undef DEFINE_DIAGNOSTIC_KIND
 150     "must-not-happen"
 151   };
 152   const char *text = _(diagnostic_kind_text[diagnostic->kind]);
 153   expanded_location s = expand_location (diagnostic->location);
 154   gcc_assert (diagnostic->kind < DK_LAST_DIAGNOSTIC_KIND);
 155
 156   return
 157     (s.file == NULL
 158      ? build_message_string ("%s: %s", progname, text)
 159      : flag_show_column && s.column != 0
 160      ? build_message_string ("%s:%d:%d: %s", s.file, s.line, s.column, text)
 161      : build_message_string ("%s:%d: %s", s.file, s.line, text));
 162 }
 163
 164 /* Take any action which is expected to happen after the diagnostic
 165    is written out.  This function does not always return.  */
 166 static void
 167 diagnostic_action_after_output (diagnostic_context *context,
 168                                 diagnostic_info *diagnostic)
 169 {
 170   switch (diagnostic->kind)
 171     {
 172     case DK_DEBUG:
 173     case DK_NOTE:
 174     case DK_ANACHRONISM:
 175     case DK_WARNING:
 176       break;
 177
 178     case DK_ERROR:
 179     case DK_SORRY:
 180       if (context->abort_on_error)
 181         real_abort ();
 182       if (flag_fatal_errors)
 183         {
 184           fnotice (stderr, "compilation terminated due to -Wfatal-errors.\n");
 185           exit (FATAL_EXIT_CODE);
 186         }
 187       break;
 188
 189     case DK_ICE:
 190       if (context->abort_on_error)
 191         real_abort ();
 192
 193       fnotice (stderr, "Please submit a full bug report,\n"
 194                "with preprocessed source if appropriate.\n"
 195                "See %s for instructions.\n", bug_report_url);
 196       exit (ICE_EXIT_CODE);
 197
 198     case DK_FATAL:
 199       if (context->abort_on_error)
 200         real_abort ();
 201
 202       fnotice (stderr, "compilation terminated.\n");
 203       exit (FATAL_EXIT_CODE);
 204
 205     default:
 206       gcc_unreachable ();
 207     }
 208 }
 209
 210 /* Prints out, if necessary, the name of the current function
 211    that caused an error.  Called from all error and warning functions.  */
 212 void
 213 diagnostic_report_current_function (diagnostic_context *context,
 214                                     diagnostic_info *diagnostic)
 215 {
 216   diagnostic_report_current_module (context);
 217   lang_hooks.print_error_function (context, input_filename, diagnostic);
 218 }
 219
 220 void
 221 diagnostic_report_current_module (diagnostic_context *context)
 222 {
 223   const struct line_map *map;
 224
 225   if (pp_needs_newline (context->printer))
 226     {
 227       pp_newline (context->printer);
 228       pp_needs_newline (context->printer) = false;
 229     }
 230
 231   if (input_location <= BUILTINS_LOCATION)
 232     return;
 233
 234   map = linemap_lookup (line_table, input_location);
 235   if (map && diagnostic_last_module_changed (context, map))
 236     {
 237       diagnostic_set_last_module (context, map);
 238       if (! MAIN_FILE_P (map))
 239         {
 240           map = INCLUDED_FROM (line_table, map);
 241           pp_verbatim (context->printer,
 242                        "In file included from %s:%d",
 243                        map->to_file, LAST_SOURCE_LINE (map));
 244           while (! MAIN_FILE_P (map))
 245             {
 246               map = INCLUDED_FROM (line_table, map);
 247               pp_verbatim (context->printer,
 248                            ",\n                 from %s:%d",
 249                            map->to_file, LAST_SOURCE_LINE (map));
 250             }
 251           pp_verbatim (context->printer, ":");
 252           pp_newline (context->printer);
 253         }
 254     }
 255 }
 256
 257 static void
 258 default_diagnostic_starter (diagnostic_context *context,
 259                             diagnostic_info *diagnostic)
 260 {
 261   diagnostic_report_current_function (context, diagnostic);
 262   pp_set_prefix (context->printer, diagnostic_build_prefix (diagnostic));
 263 }
 264
 265 static void
 266 default_diagnostic_finalizer (diagnostic_context *context,
 267                               diagnostic_info *diagnostic ATTRIBUTE_UNUSED)
 268 {
 269   pp_destroy_prefix (context->printer);
 270 }
 271
 272 /* Interface to specify diagnostic kind overrides.  Returns the
 273    previous setting, or DK_UNSPECIFIED if the parameters are out of
 274    range.  */
 275 diagnostic_t
 276 diagnostic_classify_diagnostic (diagnostic_context *context,
 277                                 int option_index,
 278                                 diagnostic_t new_kind)
 279 {
 280   diagnostic_t old_kind;
 281
 282   if (option_index <= 0
 283       || option_index >= N_OPTS
 284       || new_kind >= DK_LAST_DIAGNOSTIC_KIND)
 285     return DK_UNSPECIFIED;
 286
 287   old_kind = context->classify_diagnostic[option_index];
 288   context->classify_diagnostic[option_index] = new_kind;
 289   return old_kind;
 290 }
 291
 292 /* Report a diagnostic message (an error or a warning) as specified by
 293    DC.  This function is *the* subroutine in terms of which front-ends
 294    should implement their specific diagnostic handling modules.  The
 295    front-end independent format specifiers are exactly those described
 296    in the documentation of output_format.  */
 297
 298 void
 299 diagnostic_report_diagnostic (diagnostic_context *context,
 300                               diagnostic_info *diagnostic)
 301 {
 302   bool maybe_print_warnings_as_errors_message = false;
 303   const char *saved_format_spec;
 304
 305   /* Give preference to being able to inhibit warnings, before they
 306      get reclassified to something else.  */
 307   if (diagnostic->kind == DK_WARNING
 308       && !diagnostic_report_warnings_p ())
 309     return;
 310
 311   if (context->lock > 0)
 312     {
 313       /* If we're reporting an ICE in the middle of some other error,
 314          try to flush out the previous error, then let this one
 315          through.  Don't do this more than once.  */
 316       if (diagnostic->kind == DK_ICE && context->lock == 1)
 317         pp_flush (context->printer);
 318       else
 319         error_recursion (context);
 320     }
 321
 322   /* If the user requested that warnings be treated as errors, so be
 323      it.  Note that we do this before the next block so that
 324      individual warnings can be overridden back to warnings with
 325      -Wno-error=*.  */
 326   if (context->warning_as_error_requested
 327       && diagnostic->kind == DK_WARNING)
 328     {
 329       diagnostic->kind = DK_ERROR;
 330       maybe_print_warnings_as_errors_message = true;
 331     }
 332
 333   if (diagnostic->option_index)
 334     {
 335       /* This tests if the user provided the appropriate -Wfoo or
 336          -Wno-foo option.  */
 337       if (! option_enabled (diagnostic->option_index))
 338         return;
 339       /* This tests if the user provided the appropriate -Werror=foo
 340          option.  */
 341       if (context->classify_diagnostic[diagnostic->option_index] != DK_UNSPECIFIED)
 342         {
 343           diagnostic->kind = context->classify_diagnostic[diagnostic->option_index];
 344           maybe_print_warnings_as_errors_message = false;
 345         }
 346       /* This allows for future extensions, like temporarily disabling
 347          warnings for ranges of source code.  */
 348       if (diagnostic->kind == DK_IGNORED)
 349         return;
 350     }
 351
 352   /* If we changed the kind due to -Werror, and didn't override it, we
 353      need to print this message.  */
 354   if (context->issue_warnings_are_errors_message
 355       && maybe_print_warnings_as_errors_message)
 356     {
 357       pp_verbatim (context->printer,
 358                    "%s: warnings being treated as errors\n", progname);
 359       context->issue_warnings_are_errors_message = false;
 360     }
 361
 362   context->lock++;
 363
 364   if (diagnostic->kind == DK_ICE)
 365     {
 366 #ifndef ENABLE_CHECKING
 367       /* When not checking, ICEs are converted to fatal errors when an
 368          error has already occurred.  This is counteracted by
 369          abort_on_error.  */
 370       if ((diagnostic_kind_count (context, DK_ERROR) > 0
 371            || diagnostic_kind_count (context, DK_SORRY) > 0)
 372           && !context->abort_on_error)
 373         {
 374           expanded_location s = expand_location (diagnostic->location);
 375           fnotice (stderr, "%s:%d: confused by earlier errors, bailing out\n",
 376                    s.file, s.line);
 377           exit (ICE_EXIT_CODE);
 378         }
 379 #endif
 380       if (context->internal_error)
 381         (*context->internal_error) (diagnostic->message.format_spec,
 382                                     diagnostic->message.args_ptr);
 383     }
 384   ++diagnostic_kind_count (context, diagnostic->kind);
 385
 386   saved_format_spec = diagnostic->message.format_spec;
 387   if (context->show_option_requested && diagnostic->option_index)
 388     diagnostic->message.format_spec
 389       = ACONCAT ((diagnostic->message.format_spec,
 390                   " [", cl_options[diagnostic->option_index].opt_text, "]", NULL));
 391
 392   diagnostic->message.locus = &diagnostic->location;
 393   diagnostic->message.abstract_origin = &diagnostic->abstract_origin;
 394   diagnostic->abstract_origin = NULL;
 395   pp_format (context->printer, &diagnostic->message);
 396   (*diagnostic_starter (context)) (context, diagnostic);
 397   pp_output_formatted_text (context->printer);
 398   (*diagnostic_finalizer (context)) (context, diagnostic);
 399   pp_flush (context->printer);
 400   diagnostic_action_after_output (context, diagnostic);
 401   diagnostic->message.format_spec = saved_format_spec;
 402   diagnostic->abstract_origin = NULL;
 403
 404   context->lock--;
 405 }
 406
 407 /* Given a partial pathname as input, return another pathname that
 408    shares no directory elements with the pathname of __FILE__.  This
 409    is used by fancy_abort() to print `Internal compiler error in expr.c'
 410    instead of `Internal compiler error in ../../GCC/gcc/expr.c'.  */
 411
 412 const char *
 413 trim_filename (const char *name)
 414 {
 415   static const char this_file[] = __FILE__;
 416   const char *p = name, *q = this_file;
 417
 418   /* First skip any "../" in each filename.  This allows us to give a proper
 419      reference to a file in a subdirectory.  */
 420   while (p[0] == '.' && p[1] == '.' && IS_DIR_SEPARATOR (p[2]))
 421     p += 3;
 422
 423   while (q[0] == '.' && q[1] == '.' && IS_DIR_SEPARATOR (q[2]))
 424     q += 3;
 425
 426   /* Now skip any parts the two filenames have in common.  */
 427   while (*p == *q && *p != 0 && *q != 0)
 428     p++, q++;
 429
 430   /* Now go backwards until the previous directory separator.  */
 431   while (p > name && !IS_DIR_SEPARATOR (p[-1]))
 432     p--;
 433
 434   return p;
 435 }
 436 \f
 437 /* Standard error reporting routines in increasing order of severity.
 438    All of these take arguments like printf.  */
 439
 440 /* Text to be emitted verbatim to the error message stream; this
 441    produces no prefix and disables line-wrapping.  Use rarely.  */
 442 void
 443 verbatim (const char *gmsgid, ...)
 444 {
 445   text_info text;
 446   va_list ap;
 447
 448   va_start (ap, gmsgid);
 449   text.err_no = errno;
 450   text.args_ptr = &ap;
 451   text.format_spec = _(gmsgid);
 452   text.locus = NULL;
 453   text.abstract_origin = NULL;
 454   pp_format_verbatim (global_dc->printer, &text);
 455   pp_flush (global_dc->printer);
 456   va_end (ap);
 457 }
 458
 459 /* An informative note.  Use this for additional details on an error
 460    message.  */
 461 void
 462 inform (const char *gmsgid, ...)
 463 {
 464   diagnostic_info diagnostic;
 465   va_list ap;
 466
 467   va_start (ap, gmsgid);
 468   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_NOTE);
 469   report_diagnostic (&diagnostic);
 470   va_end (ap);
 471 }
 472
 473 /* A warning.  Use this for code which is correct according to the
 474    relevant language specification but is likely to be buggy anyway.  */
 475 void
 476 warning (int opt, const char *gmsgid, ...)
 477 {
 478   diagnostic_info diagnostic;
 479   va_list ap;
 480
 481   va_start (ap, gmsgid);
 482   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_WARNING);
 483   diagnostic.option_index = opt;
 484
 485   report_diagnostic (&diagnostic);
 486   va_end (ap);
 487 }
 488
 489 void
 490 warning0 (const char *gmsgid, ...)
 491 {
 492   diagnostic_info diagnostic;
 493   va_list ap;
 494
 495   va_start (ap, gmsgid);
 496   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_WARNING);
 497   report_diagnostic (&diagnostic);
 498   va_end (ap);
 499 }
 500
 501 /* A "pedantic" warning: issues a warning unless -pedantic-errors was
 502    given on the command line, in which case it issues an error.  Use
 503    this for diagnostics required by the relevant language standard,
 504    if you have chosen not to make them errors.
 505
 506    Note that these diagnostics are issued independent of the setting
 507    of the -pedantic command-line switch.  To get a warning enabled
 508    only with that switch, write "if (pedantic) pedwarn (...);"  */
 509 void
 510 pedwarn (const char *gmsgid, ...)
 511 {
 512   diagnostic_info diagnostic;
 513   va_list ap;
 514
 515   va_start (ap, gmsgid);
 516   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location,
 517                        pedantic_warning_kind ());
 518   report_diagnostic (&diagnostic);
 519   va_end (ap);
 520 }
 521
 522 /* A "permissive" error: issues an error unless -fpermissive was given
 523    on the command line, in which case it issues a warning.  Use this
 524    for things that really should be errors but we want to support
 525    legacy code.  */
 526
 527 void
 528 permerror (const char *gmsgid, ...)
 529 {
 530   diagnostic_info diagnostic;
 531   va_list ap;
 532
 533   va_start (ap, gmsgid);
 534   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location,
 535                        permissive_error_kind ());
 536   diagnostic.option_index = OPT_fpermissive;
 537   report_diagnostic (&diagnostic);
 538   va_end (ap);
 539 }
 540
 541
 542 /* A hard error: the code is definitely ill-formed, and an object file
 543    will not be produced.  */
 544 void
 545 error (const char *gmsgid, ...)
 546 {
 547   diagnostic_info diagnostic;
 548   va_list ap;
 549
 550   va_start (ap, gmsgid);
 551   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_ERROR);
 552   report_diagnostic (&diagnostic);
 553   va_end (ap);
 554 }
 555
 556 /* "Sorry, not implemented."  Use for a language feature which is
 557    required by the relevant specification but not implemented by GCC.
 558    An object file will not be produced.  */
 559 void
 560 sorry (const char *gmsgid, ...)
 561 {
 562   diagnostic_info diagnostic;
 563   va_list ap;
 564
 565   va_start (ap, gmsgid);
 566   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_SORRY);
 567   report_diagnostic (&diagnostic);
 568   va_end (ap);
 569 }
 570
 571 /* An error which is severe enough that we make no attempt to
 572    continue.  Do not use this for internal consistency checks; that's
 573    internal_error.  Use of this function should be rare.  */
 574 void
 575 fatal_error (const char *gmsgid, ...)
 576 {
 577   diagnostic_info diagnostic;
 578   va_list ap;
 579
 580   va_start (ap, gmsgid);
 581   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_FATAL);
 582   report_diagnostic (&diagnostic);
 583   va_end (ap);
 584
 585   gcc_unreachable ();
 586 }
 587
 588 /* An internal consistency check has failed.  We make no attempt to
 589    continue.  Note that unless there is debugging value to be had from
 590    a more specific message, or some other good reason, you should use
 591    abort () instead of calling this function directly.  */
 592 void
 593 internal_error (const char *gmsgid, ...)
 594 {
 595   diagnostic_info diagnostic;
 596   va_list ap;
 597
 598   va_start (ap, gmsgid);
 599   diagnostic_set_info (&diagnostic, gmsgid, &ap, input_location, DK_ICE);
 600   report_diagnostic (&diagnostic);
 601   va_end (ap);
 602
 603   gcc_unreachable ();
 604 }
 605 \f
 606 /* Special case error functions.  Most are implemented in terms of the
 607    above, or should be.  */
 608
 609 /* Print a diagnostic MSGID on FILE.  This is just fprintf, except it
 610    runs its second argument through gettext.  */
 611 void
 612 fnotice (FILE *file, const char *cmsgid, ...)
 613 {
 614   va_list ap;
 615
 616   va_start (ap, cmsgid);
 617   vfprintf (file, _(cmsgid), ap);
 618   va_end (ap);
 619 }
 620
 621 /* Inform the user that an error occurred while trying to report some
 622    other error.  This indicates catastrophic internal inconsistencies,
 623    so give up now.  But do try to flush out the previous error.
 624    This mustn't use internal_error, that will cause infinite recursion.  */
 625
 626 static void
 627 error_recursion (diagnostic_context *context)
 628 {
 629   diagnostic_info diagnostic;
 630
 631   if (context->lock < 3)
 632     pp_flush (context->printer);
 633
 634   fnotice (stderr,
 635            "Internal compiler error: Error reporting routines re-entered.\n");
 636
 637   /* Call diagnostic_action_after_output to get the "please submit a bug
 638      report" message.  It only looks at the kind field of diagnostic_info.  */
 639   diagnostic.kind = DK_ICE;
 640   diagnostic_action_after_output (context, &diagnostic);
 641
 642   /* Do not use gcc_unreachable here; that goes through internal_error
 643      and therefore would cause infinite recursion.  */
 644   real_abort ();
 645 }
 646
 647 /* Report an internal compiler error in a friendly manner.  This is
 648    the function that gets called upon use of abort() in the source
 649    code generally, thanks to a special macro.  */
 650
 651 void
 652 fancy_abort (const char *file, int line, const char *function)
 653 {
 654   internal_error ("in %s, at %s:%d", function, trim_filename (file), line);
 655 }
 656
 657 /* Really call the system 'abort'.  This has to go right at the end of
 658    this file, so that there are no functions after it that call abort
 659    and get the system abort instead of our macro.  */
 660 #undef abort
 661 static void
 662 real_abort (void)
 663 {
 664   abort ();
 665 }