libcpp/init.c

   1 /* CPP Library.
   2    Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4    Contributed by Per Bothner, 1994-95.
   5    Based on CCCP program by Paul Rubin, June 1986
   6    Adapted to ANSI C, Richard Stallman, Jan 1987
   7
   8 This program is free software; you can redistribute it and/or modify it
   9 under the terms of the GNU General Public License as published by the
  10 Free Software Foundation; either version 2, or (at your option) any
  11 later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "cpplib.h"
  25 #include "internal.h"
  26 #include "mkdeps.h"
  27 #include "localedir.h"
  28
  29 static void init_library (void);
  30 static void mark_named_operators (cpp_reader *);
  31 static void read_original_filename (cpp_reader *);
  32 static void read_original_directory (cpp_reader *);
  33 static void post_options (cpp_reader *);
  34
  35 /* If we have designated initializers (GCC >2.7) these tables can be
  36    initialized, constant data.  Otherwise, they have to be filled in at
  37    runtime.  */
  38 #if HAVE_DESIGNATED_INITIALIZERS
  39
  40 #define init_trigraph_map()  /* Nothing.  */
  41 #define TRIGRAPH_MAP \
  42 __extension__ const uchar _cpp_trigraph_map[UCHAR_MAX + 1] = {
  43
  44 #define END };
  45 #define s(p, v) [p] = v,
  46
  47 #else
  48
  49 #define TRIGRAPH_MAP uchar _cpp_trigraph_map[UCHAR_MAX + 1] = { 0 }; \
  50  static void init_trigraph_map (void) { \
  51  unsigned char *x = _cpp_trigraph_map;
  52
  53 #define END }
  54 #define s(p, v) x[p] = v;
  55
  56 #endif
  57
  58 TRIGRAPH_MAP
  59   s('=', '#')   s(')', ']')     s('!', '|')
  60   s('(', '[')   s('\'', '^')    s('>', '}')
  61   s('/', '\\')  s('<', '{')     s('-', '~')
  62 END
  63
  64 #undef s
  65 #undef END
  66 #undef TRIGRAPH_MAP
  67
  68 /* A set of booleans indicating what CPP features each source language
  69    requires.  */
  70 struct lang_flags
  71 {
  72   char c99;
  73   char cplusplus;
  74   char extended_numbers;
  75   char extended_identifiers;
  76   char std;
  77   char cplusplus_comments;
  78   char digraphs;
  79 };
  80
  81 static const struct lang_flags lang_defaults[] =
  82 { /*              c99 c++ xnum xid std  //   digr  */
  83   /* GNUC89   */  { 0,  0,  1,   0,  0,   1,   1     },
  84   /* GNUC99   */  { 1,  0,  1,   0,  0,   1,   1     },
  85   /* STDC89   */  { 0,  0,  0,   0,  1,   0,   0     },
  86   /* STDC94   */  { 0,  0,  0,   0,  1,   0,   1     },
  87   /* STDC99   */  { 1,  0,  1,   0,  1,   1,   1     },
  88   /* GNUCXX   */  { 0,  1,  1,   0,  0,   1,   1     },
  89   /* CXX98    */  { 0,  1,  1,   0,  1,   1,   1     },
  90   /* GNUCXX0X */  { 1,  1,  1,   0,  0,   1,   1     },
  91   /* CXX0X    */  { 1,  1,  1,   0,  1,   1,   1     },
  92   /* ASM      */  { 0,  0,  1,   0,  0,   1,   0     }
  93   /* xid should be 1 for GNUC99, STDC99, GNUCXX, CXX98, GNUCXX0X, and
  94      CXX0X when no longer experimental (when all uses of identifiers
  95      in the compiler have been audited for correct handling of
  96      extended identifiers).  */
  97 };
  98
  99 /* Sets internal flags correctly for a given language.  */
 100 void
 101 cpp_set_lang (cpp_reader *pfile, enum c_lang lang)
 102 {
 103   const struct lang_flags *l = &lang_defaults[(int) lang];
 104
 105   CPP_OPTION (pfile, lang) = lang;
 106
 107   CPP_OPTION (pfile, c99)                        = l->c99;
 108   CPP_OPTION (pfile, cplusplus)                  = l->cplusplus;
 109   CPP_OPTION (pfile, extended_numbers)           = l->extended_numbers;
 110   CPP_OPTION (pfile, extended_identifiers)       = l->extended_identifiers;
 111   CPP_OPTION (pfile, std)                        = l->std;
 112   CPP_OPTION (pfile, trigraphs)                  = l->std;
 113   CPP_OPTION (pfile, cplusplus_comments)         = l->cplusplus_comments;
 114   CPP_OPTION (pfile, digraphs)                   = l->digraphs;
 115 }
 116
 117 /* Initialize library global state.  */
 118 static void
 119 init_library (void)
 120 {
 121   static int initialized = 0;
 122
 123   if (! initialized)
 124     {
 125       initialized = 1;
 126
 127       /* Set up the trigraph map.  This doesn't need to do anything if
 128          we were compiled with a compiler that supports C99 designated
 129          initializers.  */
 130       init_trigraph_map ();
 131
 132 #ifdef ENABLE_NLS
 133        (void) bindtextdomain (PACKAGE, LOCALEDIR);
 134 #endif
 135     }
 136 }
 137
 138 /* Initialize a cpp_reader structure.  */
 139 cpp_reader *
 140 cpp_create_reader (enum c_lang lang, hash_table *table,
 141                    struct line_maps *line_table)
 142 {
 143   cpp_reader *pfile;
 144
 145   /* Initialize this instance of the library if it hasn't been already.  */
 146   init_library ();
 147
 148   pfile = XCNEW (cpp_reader);
 149
 150   cpp_set_lang (pfile, lang);
 151   CPP_OPTION (pfile, warn_multichar) = 1;
 152   CPP_OPTION (pfile, discard_comments) = 1;
 153   CPP_OPTION (pfile, discard_comments_in_macro_exp) = 1;
 154   CPP_OPTION (pfile, show_column) = 1;
 155   CPP_OPTION (pfile, tabstop) = 8;
 156   CPP_OPTION (pfile, operator_names) = 1;
 157   CPP_OPTION (pfile, warn_trigraphs) = 2;
 158   CPP_OPTION (pfile, warn_endif_labels) = 1;
 159   CPP_OPTION (pfile, warn_deprecated) = 1;
 160   CPP_OPTION (pfile, warn_long_long) = !CPP_OPTION (pfile, c99);
 161   CPP_OPTION (pfile, dollars_in_ident) = 1;
 162   CPP_OPTION (pfile, warn_dollars) = 1;
 163   CPP_OPTION (pfile, warn_variadic_macros) = 1;
 164   CPP_OPTION (pfile, warn_normalize) = normalized_C;
 165
 166   /* Default CPP arithmetic to something sensible for the host for the
 167      benefit of dumb users like fix-header.  */
 168   CPP_OPTION (pfile, precision) = CHAR_BIT * sizeof (long);
 169   CPP_OPTION (pfile, char_precision) = CHAR_BIT;
 170   CPP_OPTION (pfile, wchar_precision) = CHAR_BIT * sizeof (int);
 171   CPP_OPTION (pfile, int_precision) = CHAR_BIT * sizeof (int);
 172   CPP_OPTION (pfile, unsigned_char) = 0;
 173   CPP_OPTION (pfile, unsigned_wchar) = 1;
 174   CPP_OPTION (pfile, bytes_big_endian) = 1;  /* does not matter */
 175
 176   /* Default to no charset conversion.  */
 177   CPP_OPTION (pfile, narrow_charset) = _cpp_default_encoding ();
 178   CPP_OPTION (pfile, wide_charset) = 0;
 179
 180   /* Default the input character set to UTF-8.  */
 181   CPP_OPTION (pfile, input_charset) = _cpp_default_encoding ();
 182
 183   /* A fake empty "directory" used as the starting point for files
 184      looked up without a search path.  Name cannot be '/' because we
 185      don't want to prepend anything at all to filenames using it.  All
 186      other entries are correct zero-initialized.  */
 187   pfile->no_search_path.name = (char *) "";
 188
 189   /* Initialize the line map.  */
 190   pfile->line_table = line_table;
 191
 192   /* Initialize lexer state.  */
 193   pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
 194
 195   /* Set up static tokens.  */
 196   pfile->avoid_paste.type = CPP_PADDING;
 197   pfile->avoid_paste.val.source = NULL;
 198   pfile->eof.type = CPP_EOF;
 199   pfile->eof.flags = 0;
 200
 201   /* Create a token buffer for the lexer.  */
 202   _cpp_init_tokenrun (&pfile->base_run, 250);
 203   pfile->cur_run = &pfile->base_run;
 204   pfile->cur_token = pfile->base_run.base;
 205
 206   /* Initialize the base context.  */
 207   pfile->context = &pfile->base_context;
 208   pfile->base_context.macro = 0;
 209   pfile->base_context.prev = pfile->base_context.next = 0;
 210
 211   /* Aligned and unaligned storage.  */
 212   pfile->a_buff = _cpp_get_buff (pfile, 0);
 213   pfile->u_buff = _cpp_get_buff (pfile, 0);
 214
 215   /* The expression parser stack.  */
 216   _cpp_expand_op_stack (pfile);
 217
 218   /* Initialize the buffer obstack.  */
 219   _obstack_begin (&pfile->buffer_ob, 0, 0,
 220                   (void *(*) (long)) xmalloc,
 221                   (void (*) (void *)) free);
 222
 223   _cpp_init_files (pfile);
 224
 225   _cpp_init_hashtable (pfile, table);
 226
 227   return pfile;
 228 }
 229
 230 /* Free resources used by PFILE.  Accessing PFILE after this function
 231    returns leads to undefined behavior.  Returns the error count.  */
 232 void
 233 cpp_destroy (cpp_reader *pfile)
 234 {
 235   cpp_context *context, *contextn;
 236   tokenrun *run, *runn;
 237
 238   free (pfile->op_stack);
 239
 240   while (CPP_BUFFER (pfile) != NULL)
 241     _cpp_pop_buffer (pfile);
 242
 243   if (pfile->out.base)
 244     free (pfile->out.base);
 245
 246   if (pfile->macro_buffer)
 247     {
 248       free (pfile->macro_buffer);
 249       pfile->macro_buffer = NULL;
 250       pfile->macro_buffer_len = 0;
 251     }
 252
 253   if (pfile->deps)
 254     deps_free (pfile->deps);
 255   obstack_free (&pfile->buffer_ob, 0);
 256
 257   _cpp_destroy_hashtable (pfile);
 258   _cpp_cleanup_files (pfile);
 259   _cpp_destroy_iconv (pfile);
 260
 261   _cpp_free_buff (pfile->a_buff);
 262   _cpp_free_buff (pfile->u_buff);
 263   _cpp_free_buff (pfile->free_buffs);
 264
 265   for (run = &pfile->base_run; run; run = runn)
 266     {
 267       runn = run->next;
 268       free (run->base);
 269       if (run != &pfile->base_run)
 270         free (run);
 271     }
 272
 273   for (context = pfile->base_context.next; context; context = contextn)
 274     {
 275       contextn = context->next;
 276       free (context);
 277     }
 278
 279   free (pfile);
 280 }
 281
 282 /* This structure defines one built-in identifier.  A node will be
 283    entered in the hash table under the name NAME, with value VALUE.
 284
 285    There are two tables of these.  builtin_array holds all the
 286    "builtin" macros: these are handled by builtin_macro() in
 287    macro.c.  Builtin is somewhat of a misnomer -- the property of
 288    interest is that these macros require special code to compute their
 289    expansions.  The value is a "builtin_type" enumerator.
 290
 291    operator_array holds the C++ named operators.  These are keywords
 292    which act as aliases for punctuators.  In C++, they cannot be
 293    altered through #define, and #if recognizes them as operators.  In
 294    C, these are not entered into the hash table at all (but see
 295    <iso646.h>).  The value is a token-type enumerator.  */
 296 struct builtin
 297 {
 298   const uchar *name;
 299   unsigned short len;
 300   unsigned short value;
 301 };
 302
 303 #define B(n, t)    { DSC(n), t }
 304 static const struct builtin builtin_array[] =
 305 {
 306   B("__TIMESTAMP__",     BT_TIMESTAMP),
 307   B("__TIME__",          BT_TIME),
 308   B("__DATE__",          BT_DATE),
 309   B("__FILE__",          BT_FILE),
 310   B("__BASE_FILE__",     BT_BASE_FILE),
 311   B("__LINE__",          BT_SPECLINE),
 312   B("__INCLUDE_LEVEL__", BT_INCLUDE_LEVEL),
 313   /* Keep builtins not used for -traditional-cpp at the end, and
 314      update init_builtins() if any more are added.  */
 315   B("_Pragma",           BT_PRAGMA),
 316   B("__STDC__",          BT_STDC),
 317 };
 318
 319 static const struct builtin operator_array[] =
 320 {
 321   B("and",      CPP_AND_AND),
 322   B("and_eq",   CPP_AND_EQ),
 323   B("bitand",   CPP_AND),
 324   B("bitor",    CPP_OR),
 325   B("compl",    CPP_COMPL),
 326   B("not",      CPP_NOT),
 327   B("not_eq",   CPP_NOT_EQ),
 328   B("or",       CPP_OR_OR),
 329   B("or_eq",    CPP_OR_EQ),
 330   B("xor",      CPP_XOR),
 331   B("xor_eq",   CPP_XOR_EQ)
 332 };
 333 #undef B
 334
 335 /* Mark the C++ named operators in the hash table.  */
 336 static void
 337 mark_named_operators (cpp_reader *pfile)
 338 {
 339   const struct builtin *b;
 340
 341   for (b = operator_array;
 342        b < (operator_array + ARRAY_SIZE (operator_array));
 343        b++)
 344     {
 345       cpp_hashnode *hp = cpp_lookup (pfile, b->name, b->len);
 346       hp->flags |= NODE_OPERATOR;
 347       hp->is_directive = 0;
 348       hp->directive_index = b->value;
 349     }
 350 }
 351
 352 /* Read the builtins table above and enter them, and language-specific
 353    macros, into the hash table.  HOSTED is true if this is a hosted
 354    environment.  */
 355 void
 356 cpp_init_builtins (cpp_reader *pfile, int hosted)
 357 {
 358   const struct builtin *b;
 359   size_t n = ARRAY_SIZE (builtin_array);
 360
 361   if (CPP_OPTION (pfile, traditional))
 362     n -= 2;
 363   else if (! CPP_OPTION (pfile, stdc_0_in_system_headers)
 364            || CPP_OPTION (pfile, std))
 365     {
 366       n--;
 367       _cpp_define_builtin (pfile, "__STDC__ 1");
 368     }
 369
 370   for (b = builtin_array; b < builtin_array + n; b++)
 371     {
 372       cpp_hashnode *hp = cpp_lookup (pfile, b->name, b->len);
 373       hp->type = NT_MACRO;
 374       hp->flags |= NODE_BUILTIN | NODE_WARN;
 375       hp->value.builtin = (enum builtin_type) b->value;
 376     }
 377
 378   if (CPP_OPTION (pfile, cplusplus))
 379     _cpp_define_builtin (pfile, "__cplusplus 1");
 380   else if (CPP_OPTION (pfile, lang) == CLK_ASM)
 381     _cpp_define_builtin (pfile, "__ASSEMBLER__ 1");
 382   else if (CPP_OPTION (pfile, lang) == CLK_STDC94)
 383     _cpp_define_builtin (pfile, "__STDC_VERSION__ 199409L");
 384   else if (CPP_OPTION (pfile, c99))
 385     _cpp_define_builtin (pfile, "__STDC_VERSION__ 199901L");
 386
 387   if (hosted)
 388     _cpp_define_builtin (pfile, "__STDC_HOSTED__ 1");
 389   else
 390     _cpp_define_builtin (pfile, "__STDC_HOSTED__ 0");
 391
 392   if (CPP_OPTION (pfile, objc))
 393     _cpp_define_builtin (pfile, "__OBJC__ 1");
 394 }
 395
 396 /* Sanity-checks are dependent on command-line options, so it is
 397    called as a subroutine of cpp_read_main_file ().  */
 398 #if ENABLE_CHECKING
 399 static void sanity_checks (cpp_reader *);
 400 static void sanity_checks (cpp_reader *pfile)
 401 {
 402   cppchar_t test = 0;
 403   size_t max_precision = 2 * CHAR_BIT * sizeof (cpp_num_part);
 404
 405   /* Sanity checks for assumptions about CPP arithmetic and target
 406      type precisions made by cpplib.  */
 407   test--;
 408   if (test < 1)
 409     cpp_error (pfile, CPP_DL_ICE, "cppchar_t must be an unsigned type");
 410
 411   if (CPP_OPTION (pfile, precision) > max_precision)
 412     cpp_error (pfile, CPP_DL_ICE,
 413                "preprocessor arithmetic has maximum precision of %lu bits;"
 414                " target requires %lu bits",
 415                (unsigned long) max_precision,
 416                (unsigned long) CPP_OPTION (pfile, precision));
 417
 418   if (CPP_OPTION (pfile, precision) < CPP_OPTION (pfile, int_precision))
 419     cpp_error (pfile, CPP_DL_ICE,
 420                "CPP arithmetic must be at least as precise as a target int");
 421
 422   if (CPP_OPTION (pfile, char_precision) < 8)
 423     cpp_error (pfile, CPP_DL_ICE, "target char is less than 8 bits wide");
 424
 425   if (CPP_OPTION (pfile, wchar_precision) < CPP_OPTION (pfile, char_precision))
 426     cpp_error (pfile, CPP_DL_ICE,
 427                "target wchar_t is narrower than target char");
 428
 429   if (CPP_OPTION (pfile, int_precision) < CPP_OPTION (pfile, char_precision))
 430     cpp_error (pfile, CPP_DL_ICE,
 431                "target int is narrower than target char");
 432
 433   /* This is assumed in eval_token() and could be fixed if necessary.  */
 434   if (sizeof (cppchar_t) > sizeof (cpp_num_part))
 435     cpp_error (pfile, CPP_DL_ICE,
 436                "CPP half-integer narrower than CPP character");
 437
 438   if (CPP_OPTION (pfile, wchar_precision) > BITS_PER_CPPCHAR_T)
 439     cpp_error (pfile, CPP_DL_ICE,
 440                "CPP on this host cannot handle wide character constants over"
 441                " %lu bits, but the target requires %lu bits",
 442                (unsigned long) BITS_PER_CPPCHAR_T,
 443                (unsigned long) CPP_OPTION (pfile, wchar_precision));
 444 }
 445 #else
 446 # define sanity_checks(PFILE)
 447 #endif
 448
 449 /* This is called after options have been parsed, and partially
 450    processed.  */
 451 void
 452 cpp_post_options (cpp_reader *pfile)
 453 {
 454   sanity_checks (pfile);
 455
 456   post_options (pfile);
 457
 458   /* Mark named operators before handling command line macros.  */
 459   if (CPP_OPTION (pfile, cplusplus) && CPP_OPTION (pfile, operator_names))
 460     mark_named_operators (pfile);
 461 }
 462
 463 /* Setup for processing input from the file named FNAME, or stdin if
 464    it is the empty string.  Return the original filename
 465    on success (e.g. foo.i->foo.c), or NULL on failure.  */
 466 const char *
 467 cpp_read_main_file (cpp_reader *pfile, const char *fname)
 468 {
 469   if (CPP_OPTION (pfile, deps.style) != DEPS_NONE)
 470     {
 471       if (!pfile->deps)
 472         pfile->deps = deps_init ();
 473
 474       /* Set the default target (if there is none already).  */
 475       deps_add_default_target (pfile->deps, fname);
 476     }
 477
 478   pfile->main_file
 479     = _cpp_find_file (pfile, fname, &pfile->no_search_path, false, 0);
 480   if (_cpp_find_failed (pfile->main_file))
 481     return NULL;
 482
 483   _cpp_stack_file (pfile, pfile->main_file, false);
 484
 485   /* For foo.i, read the original filename foo.c now, for the benefit
 486      of the front ends.  */
 487   if (CPP_OPTION (pfile, preprocessed))
 488     {
 489       read_original_filename (pfile);
 490       fname = pfile->line_table->maps[pfile->line_table->used-1].to_file;
 491     }
 492   return fname;
 493 }
 494
 495 /* For preprocessed files, if the first tokens are of the form # NUM.
 496    handle the directive so we know the original file name.  This will
 497    generate file_change callbacks, which the front ends must handle
 498    appropriately given their state of initialization.  */
 499 static void
 500 read_original_filename (cpp_reader *pfile)
 501 {
 502   const cpp_token *token, *token1;
 503
 504   /* Lex ahead; if the first tokens are of the form # NUM, then
 505      process the directive, otherwise back up.  */
 506   token = _cpp_lex_direct (pfile);
 507   if (token->type == CPP_HASH)
 508     {
 509       pfile->state.in_directive = 1;
 510       token1 = _cpp_lex_direct (pfile);
 511       _cpp_backup_tokens (pfile, 1);
 512       pfile->state.in_directive = 0;
 513
 514       /* If it's a #line directive, handle it.  */
 515       if (token1->type == CPP_NUMBER)
 516         {
 517           _cpp_handle_directive (pfile, token->flags & PREV_WHITE);
 518           read_original_directory (pfile);
 519           return;
 520         }
 521     }
 522
 523   /* Backup as if nothing happened.  */
 524   _cpp_backup_tokens (pfile, 1);
 525 }
 526
 527 /* For preprocessed files, if the tokens following the first filename
 528    line is of the form # <line> "/path/name//", handle the
 529    directive so we know the original current directory.  */
 530 static void
 531 read_original_directory (cpp_reader *pfile)
 532 {
 533   const cpp_token *hash, *token;
 534
 535   /* Lex ahead; if the first tokens are of the form # NUM, then
 536      process the directive, otherwise back up.  */
 537   hash = _cpp_lex_direct (pfile);
 538   if (hash->type != CPP_HASH)
 539     {
 540       _cpp_backup_tokens (pfile, 1);
 541       return;
 542     }
 543
 544   token = _cpp_lex_direct (pfile);
 545
 546   if (token->type != CPP_NUMBER)
 547     {
 548       _cpp_backup_tokens (pfile, 2);
 549       return;
 550     }
 551
 552   token = _cpp_lex_direct (pfile);
 553
 554   if (token->type != CPP_STRING
 555       || ! (token->val.str.len >= 5
 556             && token->val.str.text[token->val.str.len-2] == '/'
 557             && token->val.str.text[token->val.str.len-3] == '/'))
 558     {
 559       _cpp_backup_tokens (pfile, 3);
 560       return;
 561     }
 562
 563   if (pfile->cb.dir_change)
 564     {
 565       char *debugdir = (char *) alloca (token->val.str.len - 3);
 566
 567       memcpy (debugdir, (const char *) token->val.str.text + 1,
 568               token->val.str.len - 4);
 569       debugdir[token->val.str.len - 4] = '\0';
 570
 571       pfile->cb.dir_change (pfile, debugdir);
 572     }
 573 }
 574
 575 /* This is called at the end of preprocessing.  It pops the last
 576    buffer and writes dependency output, and returns the number of
 577    errors.
 578
 579    Maybe it should also reset state, such that you could call
 580    cpp_start_read with a new filename to restart processing.  */
 581 int
 582 cpp_finish (cpp_reader *pfile, FILE *deps_stream)
 583 {
 584   /* Warn about unused macros before popping the final buffer.  */
 585   if (CPP_OPTION (pfile, warn_unused_macros))
 586     cpp_forall_identifiers (pfile, _cpp_warn_if_unused_macro, NULL);
 587
 588   /* lex.c leaves the final buffer on the stack.  This it so that
 589      it returns an unending stream of CPP_EOFs to the client.  If we
 590      popped the buffer, we'd dereference a NULL buffer pointer and
 591      segfault.  It's nice to allow the client to do worry-free excess
 592      cpp_get_token calls.  */
 593   while (pfile->buffer)
 594     _cpp_pop_buffer (pfile);
 595
 596   /* Don't write the deps file if there are errors.  */
 597   if (CPP_OPTION (pfile, deps.style) != DEPS_NONE
 598       && deps_stream && pfile->errors == 0)
 599     {
 600       deps_write (pfile->deps, deps_stream, 72);
 601
 602       if (CPP_OPTION (pfile, deps.phony_targets))
 603         deps_phony_targets (pfile->deps, deps_stream);
 604     }
 605
 606   /* Report on headers that could use multiple include guards.  */
 607   if (CPP_OPTION (pfile, print_include_names))
 608     _cpp_report_missing_guards (pfile);
 609
 610   return pfile->errors;
 611 }
 612
 613 static void
 614 post_options (cpp_reader *pfile)
 615 {
 616   /* -Wtraditional is not useful in C++ mode.  */
 617   if (CPP_OPTION (pfile, cplusplus))
 618     CPP_OPTION (pfile, warn_traditional) = 0;
 619
 620   /* Permanently disable macro expansion if we are rescanning
 621      preprocessed text.  Read preprocesed source in ISO mode.  */
 622   if (CPP_OPTION (pfile, preprocessed))
 623     {
 624       pfile->state.prevent_expansion = 1;
 625       CPP_OPTION (pfile, traditional) = 0;
 626     }
 627
 628   if (CPP_OPTION (pfile, warn_trigraphs) == 2)
 629     CPP_OPTION (pfile, warn_trigraphs) = !CPP_OPTION (pfile, trigraphs);
 630
 631   if (CPP_OPTION (pfile, traditional))
 632     {
 633       CPP_OPTION (pfile, cplusplus_comments) = 0;
 634
 635       /* Traditional CPP does not accurately track column information.  */
 636       CPP_OPTION (pfile, show_column) = 0;
 637       CPP_OPTION (pfile, trigraphs) = 0;
 638       CPP_OPTION (pfile, warn_trigraphs) = 0;
 639     }
 640 }