contrib/gcc-3.4/gcc/cppinit.c

   1 /* CPP Library.
   2    Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003, 2004 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "cpplib.h"
  25 #include "cpphash.h"
  26 #include "mkdeps.h"
  27
  28 static void init_library (void);
  29 static void mark_named_operators (cpp_reader *);
  30 static void read_original_filename (cpp_reader *);
  31 static void read_original_directory (cpp_reader *);
  32 static void post_options (cpp_reader *);
  33
  34 /* If we have designated initializers (GCC >2.7) these tables can be
  35    initialized, constant data.  Otherwise, they have to be filled in at
  36    runtime.  */
  37 #if HAVE_DESIGNATED_INITIALIZERS
  38
  39 #define init_trigraph_map()  /* Nothing.  */
  40 #define TRIGRAPH_MAP \
  41 __extension__ const uchar _cpp_trigraph_map[UCHAR_MAX + 1] = {
  42
  43 #define END };
  44 #define s(p, v) [p] = v,
  45
  46 #else
  47
  48 #define TRIGRAPH_MAP uchar _cpp_trigraph_map[UCHAR_MAX + 1] = { 0 }; \
  49  static void init_trigraph_map (void) { \
  50  unsigned char *x = _cpp_trigraph_map;
  51
  52 #define END }
  53 #define s(p, v) x[p] = v;
  54
  55 #endif
  56
  57 TRIGRAPH_MAP
  58   s('=', '#')   s(')', ']')     s('!', '|')
  59   s('(', '[')   s('\'', '^')    s('>', '}')
  60   s('/', '\\')  s('<', '{')     s('-', '~')
  61 END
  62
  63 #undef s
  64 #undef END
  65 #undef TRIGRAPH_MAP
  66
  67 /* A set of booleans indicating what CPP features each source language
  68    requires.  */
  69 struct lang_flags
  70 {
  71   char c99;
  72   char cplusplus;
  73   char extended_numbers;
  74   char std;
  75   char cplusplus_comments;
  76   char digraphs;
  77 };
  78
  79 static const struct lang_flags lang_defaults[] =
  80 { /*              c99 c++ xnum std  //   digr  */
  81   /* GNUC89 */  { 0,  0,  1,   0,   1,   1     },
  82   /* GNUC99 */  { 1,  0,  1,   0,   1,   1     },
  83   /* STDC89 */  { 0,  0,  0,   1,   0,   0     },
  84   /* STDC94 */  { 0,  0,  0,   1,   0,   1     },
  85   /* STDC99 */  { 1,  0,  1,   1,   1,   1     },
  86   /* GNUCXX */  { 0,  1,  1,   0,   1,   1     },
  87   /* CXX98  */  { 0,  1,  1,   1,   1,   1     },
  88   /* ASM    */  { 0,  0,  1,   0,   1,   0     }
  89 };
  90
  91 /* Sets internal flags correctly for a given language.  */
  92 void
  93 cpp_set_lang (cpp_reader *pfile, enum c_lang lang)
  94 {
  95   const struct lang_flags *l = &lang_defaults[(int) lang];
  96
  97   CPP_OPTION (pfile, lang) = lang;
  98
  99   CPP_OPTION (pfile, c99)                = l->c99;
 100   CPP_OPTION (pfile, cplusplus)          = l->cplusplus;
 101   CPP_OPTION (pfile, extended_numbers)   = l->extended_numbers;
 102   CPP_OPTION (pfile, std)                = l->std;
 103   CPP_OPTION (pfile, trigraphs)          = l->std;
 104   CPP_OPTION (pfile, cplusplus_comments) = l->cplusplus_comments;
 105   CPP_OPTION (pfile, digraphs)           = l->digraphs;
 106 }
 107
 108 /* Initialize library global state.  */
 109 static void
 110 init_library (void)
 111 {
 112   static int initialized = 0;
 113
 114   if (! initialized)
 115     {
 116       initialized = 1;
 117
 118       /* Set up the trigraph map.  This doesn't need to do anything if
 119          we were compiled with a compiler that supports C99 designated
 120          initializers.  */
 121       init_trigraph_map ();
 122     }
 123 }
 124
 125 /* Initialize a cpp_reader structure.  */
 126 cpp_reader *
 127 cpp_create_reader (enum c_lang lang, hash_table *table)
 128 {
 129   cpp_reader *pfile;
 130
 131   /* Initialize this instance of the library if it hasn't been already.  */
 132   init_library ();
 133
 134   pfile = xcalloc (1, sizeof (cpp_reader));
 135
 136   cpp_set_lang (pfile, lang);
 137   CPP_OPTION (pfile, warn_multichar) = 1;
 138   CPP_OPTION (pfile, discard_comments) = 1;
 139   CPP_OPTION (pfile, discard_comments_in_macro_exp) = 1;
 140   CPP_OPTION (pfile, show_column) = 1;
 141   CPP_OPTION (pfile, tabstop) = 8;
 142   CPP_OPTION (pfile, operator_names) = 1;
 143   CPP_OPTION (pfile, warn_trigraphs) = 2;
 144   CPP_OPTION (pfile, warn_endif_labels) = 1;
 145   CPP_OPTION (pfile, warn_deprecated) = 1;
 146   CPP_OPTION (pfile, warn_long_long) = !CPP_OPTION (pfile, c99);
 147   CPP_OPTION (pfile, dollars_in_ident) = 1;
 148   CPP_OPTION (pfile, warn_dollars) = 1;
 149
 150   /* Default CPP arithmetic to something sensible for the host for the
 151      benefit of dumb users like fix-header.  */
 152   CPP_OPTION (pfile, precision) = CHAR_BIT * sizeof (long);
 153   CPP_OPTION (pfile, char_precision) = CHAR_BIT;
 154   CPP_OPTION (pfile, wchar_precision) = CHAR_BIT * sizeof (int);
 155   CPP_OPTION (pfile, int_precision) = CHAR_BIT * sizeof (int);
 156   CPP_OPTION (pfile, unsigned_char) = 0;
 157   CPP_OPTION (pfile, unsigned_wchar) = 1;
 158   CPP_OPTION (pfile, bytes_big_endian) = 1;  /* does not matter */
 159
 160   /* Default to locale/UTF-8.  */
 161   CPP_OPTION (pfile, narrow_charset) = _cpp_default_encoding ();
 162   CPP_OPTION (pfile, wide_charset) = 0;
 163   CPP_OPTION (pfile, input_charset) = _cpp_default_encoding ();
 164
 165   /* A fake empty "directory" used as the starting point for files
 166      looked up without a search path.  Name cannot be '/' because we
 167      don't want to prepend anything at all to filenames using it.  All
 168      other entries are correct zero-initialized.  */
 169   pfile->no_search_path.name = (char *) "";
 170
 171   /* Initialize the line map.  Start at logical line 1, so we can use
 172      a line number of zero for special states.  */
 173   linemap_init (&pfile->line_maps);
 174   pfile->line = 1;
 175
 176   /* Initialize lexer state.  */
 177   pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
 178
 179   /* Set up static tokens.  */
 180   pfile->avoid_paste.type = CPP_PADDING;
 181   pfile->avoid_paste.val.source = NULL;
 182   pfile->eof.type = CPP_EOF;
 183   pfile->eof.flags = 0;
 184
 185   /* Create a token buffer for the lexer.  */
 186   _cpp_init_tokenrun (&pfile->base_run, 250);
 187   pfile->cur_run = &pfile->base_run;
 188   pfile->cur_token = pfile->base_run.base;
 189
 190   /* Initialize the base context.  */
 191   pfile->context = &pfile->base_context;
 192   pfile->base_context.macro = 0;
 193   pfile->base_context.prev = pfile->base_context.next = 0;
 194
 195   /* Aligned and unaligned storage.  */
 196   pfile->a_buff = _cpp_get_buff (pfile, 0);
 197   pfile->u_buff = _cpp_get_buff (pfile, 0);
 198
 199   /* The expression parser stack.  */
 200   _cpp_expand_op_stack (pfile);
 201
 202   /* Initialize the buffer obstack.  */
 203   _obstack_begin (&pfile->buffer_ob, 0, 0,
 204                   (void *(*) (long)) xmalloc,
 205                   (void (*) (void *)) free);
 206
 207   _cpp_init_files (pfile);
 208
 209   _cpp_init_hashtable (pfile, table);
 210
 211   return pfile;
 212 }
 213
 214 /* Free resources used by PFILE.  Accessing PFILE after this function
 215    returns leads to undefined behavior.  Returns the error count.  */
 216 void
 217 cpp_destroy (cpp_reader *pfile)
 218 {
 219   cpp_context *context, *contextn;
 220   tokenrun *run, *runn;
 221
 222   free (pfile->op_stack);
 223
 224   while (CPP_BUFFER (pfile) != NULL)
 225     _cpp_pop_buffer (pfile);
 226
 227   if (pfile->out.base)
 228     free (pfile->out.base);
 229
 230   if (pfile->macro_buffer)
 231     {
 232       free (pfile->macro_buffer);
 233       pfile->macro_buffer = NULL;
 234       pfile->macro_buffer_len = 0;
 235     }
 236
 237   if (pfile->deps)
 238     deps_free (pfile->deps);
 239   obstack_free (&pfile->buffer_ob, 0);
 240
 241   _cpp_destroy_hashtable (pfile);
 242   _cpp_cleanup_files (pfile);
 243   _cpp_destroy_iconv (pfile);
 244
 245   _cpp_free_buff (pfile->a_buff);
 246   _cpp_free_buff (pfile->u_buff);
 247   _cpp_free_buff (pfile->free_buffs);
 248
 249   for (run = &pfile->base_run; run; run = runn)
 250     {
 251       runn = run->next;
 252       free (run->base);
 253       if (run != &pfile->base_run)
 254         free (run);
 255     }
 256
 257   for (context = pfile->base_context.next; context; context = contextn)
 258     {
 259       contextn = context->next;
 260       free (context);
 261     }
 262
 263   linemap_free (&pfile->line_maps);
 264   free (pfile);
 265 }
 266
 267 /* This structure defines one built-in identifier.  A node will be
 268    entered in the hash table under the name NAME, with value VALUE.
 269
 270    There are two tables of these.  builtin_array holds all the
 271    "builtin" macros: these are handled by builtin_macro() in
 272    cppmacro.c.  Builtin is somewhat of a misnomer -- the property of
 273    interest is that these macros require special code to compute their
 274    expansions.  The value is a "builtin_type" enumerator.
 275
 276    operator_array holds the C++ named operators.  These are keywords
 277    which act as aliases for punctuators.  In C++, they cannot be
 278    altered through #define, and #if recognizes them as operators.  In
 279    C, these are not entered into the hash table at all (but see
 280    <iso646.h>).  The value is a token-type enumerator.  */
 281 struct builtin
 282 {
 283   const uchar *name;
 284   unsigned short len;
 285   unsigned short value;
 286 };
 287
 288 #define B(n, t)    { DSC(n), t }
 289 static const struct builtin builtin_array[] =
 290 {
 291   B("__TIME__",          BT_TIME),
 292   B("__DATE__",          BT_DATE),
 293   B("__FILE__",          BT_FILE),
 294   B("__BASE_FILE__",     BT_BASE_FILE),
 295   B("__LINE__",          BT_SPECLINE),
 296   B("__INCLUDE_LEVEL__", BT_INCLUDE_LEVEL),
 297   /* Keep builtins not used for -traditional-cpp at the end, and
 298      update init_builtins() if any more are added.  */
 299   B("_Pragma",           BT_PRAGMA),
 300   B("__STDC__",          BT_STDC),
 301 };
 302
 303 static const struct builtin operator_array[] =
 304 {
 305   B("and",      CPP_AND_AND),
 306   B("and_eq",   CPP_AND_EQ),
 307   B("bitand",   CPP_AND),
 308   B("bitor",    CPP_OR),
 309   B("compl",    CPP_COMPL),
 310   B("not",      CPP_NOT),
 311   B("not_eq",   CPP_NOT_EQ),
 312   B("or",       CPP_OR_OR),
 313   B("or_eq",    CPP_OR_EQ),
 314   B("xor",      CPP_XOR),
 315   B("xor_eq",   CPP_XOR_EQ)
 316 };
 317 #undef B
 318
 319 /* Mark the C++ named operators in the hash table.  */
 320 static void
 321 mark_named_operators (cpp_reader *pfile)
 322 {
 323   const struct builtin *b;
 324
 325   for (b = operator_array;
 326        b < (operator_array + ARRAY_SIZE (operator_array));
 327        b++)
 328     {
 329       cpp_hashnode *hp = cpp_lookup (pfile, b->name, b->len);
 330       hp->flags |= NODE_OPERATOR;
 331       hp->is_directive = 0;
 332       hp->directive_index = b->value;
 333     }
 334 }
 335
 336 /* Read the builtins table above and enter them, and language-specific
 337    macros, into the hash table.  HOSTED is true if this is a hosted
 338    environment.  */
 339 void
 340 cpp_init_builtins (cpp_reader *pfile, int hosted)
 341 {
 342   const struct builtin *b;
 343   size_t n = ARRAY_SIZE (builtin_array);
 344
 345   if (CPP_OPTION (pfile, traditional))
 346     n -= 2;
 347
 348   for(b = builtin_array; b < builtin_array + n; b++)
 349     {
 350       cpp_hashnode *hp = cpp_lookup (pfile, b->name, b->len);
 351       hp->type = NT_MACRO;
 352       hp->flags |= NODE_BUILTIN | NODE_WARN;
 353       hp->value.builtin = b->value;
 354     }
 355
 356   if (CPP_OPTION (pfile, cplusplus))
 357     _cpp_define_builtin (pfile, "__cplusplus 1");
 358   else if (CPP_OPTION (pfile, lang) == CLK_ASM)
 359     _cpp_define_builtin (pfile, "__ASSEMBLER__ 1");
 360   else if (CPP_OPTION (pfile, lang) == CLK_STDC94)
 361     _cpp_define_builtin (pfile, "__STDC_VERSION__ 199409L");
 362   else if (CPP_OPTION (pfile, c99))
 363     _cpp_define_builtin (pfile, "__STDC_VERSION__ 199901L");
 364
 365   if (hosted)
 366     _cpp_define_builtin (pfile, "__STDC_HOSTED__ 1");
 367   else
 368     _cpp_define_builtin (pfile, "__STDC_HOSTED__ 0");
 369
 370   if (CPP_OPTION (pfile, objc))
 371     _cpp_define_builtin (pfile, "__OBJC__ 1");
 372 }
 373
 374 /* Sanity-checks are dependent on command-line options, so it is
 375    called as a subroutine of cpp_read_main_file ().  */
 376 #if ENABLE_CHECKING
 377 static void sanity_checks (cpp_reader *);
 378 static void sanity_checks (cpp_reader *pfile)
 379 {
 380   cppchar_t test = 0;
 381   size_t max_precision = 2 * CHAR_BIT * sizeof (cpp_num_part);
 382
 383   /* Sanity checks for assumptions about CPP arithmetic and target
 384      type precisions made by cpplib.  */
 385   test--;
 386   if (test < 1)
 387     cpp_error (pfile, CPP_DL_ICE, "cppchar_t must be an unsigned type");
 388
 389   if (CPP_OPTION (pfile, precision) > max_precision)
 390     cpp_error (pfile, CPP_DL_ICE,
 391                "preprocessor arithmetic has maximum precision of %lu bits;"
 392                " target requires %lu bits",
 393                (unsigned long) max_precision,
 394                (unsigned long) CPP_OPTION (pfile, precision));
 395
 396   if (CPP_OPTION (pfile, precision) < CPP_OPTION (pfile, int_precision))
 397     cpp_error (pfile, CPP_DL_ICE,
 398                "CPP arithmetic must be at least as precise as a target int");
 399
 400   if (CPP_OPTION (pfile, char_precision) < 8)
 401     cpp_error (pfile, CPP_DL_ICE, "target char is less than 8 bits wide");
 402
 403   if (CPP_OPTION (pfile, wchar_precision) < CPP_OPTION (pfile, char_precision))
 404     cpp_error (pfile, CPP_DL_ICE,
 405                "target wchar_t is narrower than target char");
 406
 407   if (CPP_OPTION (pfile, int_precision) < CPP_OPTION (pfile, char_precision))
 408     cpp_error (pfile, CPP_DL_ICE,
 409                "target int is narrower than target char");
 410
 411   /* This is assumed in eval_token() and could be fixed if necessary.  */
 412   if (sizeof (cppchar_t) > sizeof (cpp_num_part))
 413     cpp_error (pfile, CPP_DL_ICE,
 414                "CPP half-integer narrower than CPP character");
 415
 416   if (CPP_OPTION (pfile, wchar_precision) > BITS_PER_CPPCHAR_T)
 417     cpp_error (pfile, CPP_DL_ICE,
 418                "CPP on this host cannot handle wide character constants over"
 419                " %lu bits, but the target requires %lu bits",
 420                (unsigned long) BITS_PER_CPPCHAR_T,
 421                (unsigned long) CPP_OPTION (pfile, wchar_precision));
 422 }
 423 #else
 424 # define sanity_checks(PFILE)
 425 #endif
 426
 427 /* Add a dependency target.  Can be called any number of times before
 428    cpp_read_main_file().  If no targets have been added before
 429    cpp_read_main_file(), then the default target is used.  */
 430 void
 431 cpp_add_dependency_target (cpp_reader *pfile, const char *target, int quote)
 432 {
 433   if (!pfile->deps)
 434     pfile->deps = deps_init ();
 435
 436   deps_add_target (pfile->deps, target, quote);
 437 }
 438
 439 /* This is called after options have been parsed, and partially
 440    processed.  */
 441 void
 442 cpp_post_options (cpp_reader *pfile)
 443 {
 444   sanity_checks (pfile);
 445
 446   post_options (pfile);
 447
 448   /* Mark named operators before handling command line macros.  */
 449   if (CPP_OPTION (pfile, cplusplus) && CPP_OPTION (pfile, operator_names))
 450     mark_named_operators (pfile);
 451 }
 452
 453 /* Setup for processing input from the file named FNAME, or stdin if
 454    it is the empty string.  Return the original filename
 455    on success (e.g. foo.i->foo.c), or NULL on failure.  */
 456 const char *
 457 cpp_read_main_file (cpp_reader *pfile, const char *fname)
 458 {
 459   if (CPP_OPTION (pfile, deps.style) != DEPS_NONE)
 460     {
 461       if (!pfile->deps)
 462         pfile->deps = deps_init ();
 463
 464       /* Set the default target (if there is none already).  */
 465       deps_add_default_target (pfile->deps, fname);
 466     }
 467
 468   pfile->main_file
 469     = _cpp_find_file (pfile, fname, &pfile->no_search_path, false, 0);
 470   if (_cpp_find_failed (pfile->main_file))
 471     return NULL;
 472
 473   _cpp_stack_file (pfile, pfile->main_file, false);
 474
 475   /* For foo.i, read the original filename foo.c now, for the benefit
 476      of the front ends.  */
 477   if (CPP_OPTION (pfile, preprocessed))
 478     {
 479       read_original_filename (pfile);
 480       if (!pfile->map)
 481         return NULL;
 482       fname = pfile->map->to_file;
 483     }
 484   return fname;
 485 }
 486
 487 /* For preprocessed files, if the first tokens are of the form # NUM.
 488    handle the directive so we know the original file name.  This will
 489    generate file_change callbacks, which the front ends must handle
 490    appropriately given their state of initialization.  */
 491 static void
 492 read_original_filename (cpp_reader *pfile)
 493 {
 494   const cpp_token *token, *token1;
 495
 496   /* Lex ahead; if the first tokens are of the form # NUM, then
 497      process the directive, otherwise back up.  */
 498   token = _cpp_lex_direct (pfile);
 499   if (token->type == CPP_HASH)
 500     {
 501       pfile->state.in_directive = 1;
 502       token1 = _cpp_lex_direct (pfile);
 503       _cpp_backup_tokens (pfile, 1);
 504       pfile->state.in_directive = 0;
 505
 506       /* If it's a #line directive, handle it.  */
 507       if (token1->type == CPP_NUMBER)
 508         {
 509           _cpp_handle_directive (pfile, token->flags & PREV_WHITE);
 510           read_original_directory (pfile);
 511           return;
 512         }
 513     }
 514
 515   /* Backup as if nothing happened.  */
 516   _cpp_backup_tokens (pfile, 1);
 517 }
 518
 519 /* For preprocessed files, if the tokens following the first filename
 520    line is of the form # <line> "/path/name//", handle the
 521    directive so we know the original current directory.  */
 522 static void
 523 read_original_directory (cpp_reader *pfile)
 524 {
 525   const cpp_token *hash, *token;
 526
 527   /* Lex ahead; if the first tokens are of the form # NUM, then
 528      process the directive, otherwise back up.  */
 529   hash = _cpp_lex_direct (pfile);
 530   if (hash->type != CPP_HASH)
 531     {
 532       _cpp_backup_tokens (pfile, 1);
 533       return;
 534     }
 535
 536   token = _cpp_lex_direct (pfile);
 537
 538   if (token->type != CPP_NUMBER)
 539     {
 540       _cpp_backup_tokens (pfile, 2);
 541       return;
 542     }
 543
 544   token = _cpp_lex_direct (pfile);
 545
 546   if (token->type != CPP_STRING
 547       || ! (token->val.str.len >= 5
 548             && token->val.str.text[token->val.str.len-2] == '/'
 549             && token->val.str.text[token->val.str.len-3] == '/'))
 550     {
 551       _cpp_backup_tokens (pfile, 3);
 552       return;
 553     }
 554
 555   if (pfile->cb.dir_change)
 556     {
 557       char *debugdir = alloca (token->val.str.len - 3);
 558
 559       memcpy (debugdir, (const char *) token->val.str.text + 1,
 560               token->val.str.len - 4);
 561       debugdir[token->val.str.len - 4] = '\0';
 562
 563       pfile->cb.dir_change (pfile, debugdir);
 564     }
 565 }
 566
 567 /* This is called at the end of preprocessing.  It pops the last
 568    buffer and writes dependency output, and returns the number of
 569    errors.
 570
 571    Maybe it should also reset state, such that you could call
 572    cpp_start_read with a new filename to restart processing.  */
 573 int
 574 cpp_finish (cpp_reader *pfile, FILE *deps_stream)
 575 {
 576   /* Warn about unused macros before popping the final buffer.  */
 577   if (CPP_OPTION (pfile, warn_unused_macros))
 578     cpp_forall_identifiers (pfile, _cpp_warn_if_unused_macro, NULL);
 579
 580   /* cpplex.c leaves the final buffer on the stack.  This it so that
 581      it returns an unending stream of CPP_EOFs to the client.  If we
 582      popped the buffer, we'd dereference a NULL buffer pointer and
 583      segfault.  It's nice to allow the client to do worry-free excess
 584      cpp_get_token calls.  */
 585   while (pfile->buffer)
 586     _cpp_pop_buffer (pfile);
 587
 588   /* Don't write the deps file if there are errors.  */
 589   if (CPP_OPTION (pfile, deps.style) != DEPS_NONE
 590       && deps_stream && pfile->errors == 0)
 591     {
 592       deps_write (pfile->deps, deps_stream, 72);
 593
 594       if (CPP_OPTION (pfile, deps.phony_targets))
 595         deps_phony_targets (pfile->deps, deps_stream);
 596     }
 597
 598   /* Report on headers that could use multiple include guards.  */
 599   if (CPP_OPTION (pfile, print_include_names))
 600     _cpp_report_missing_guards (pfile);
 601
 602   return pfile->errors;
 603 }
 604
 605 static void
 606 post_options (cpp_reader *pfile)
 607 {
 608   /* -Wtraditional is not useful in C++ mode.  */
 609   if (CPP_OPTION (pfile, cplusplus))
 610     CPP_OPTION (pfile, warn_traditional) = 0;
 611
 612   /* Permanently disable macro expansion if we are rescanning
 613      preprocessed text.  Read preprocesed source in ISO mode.  */
 614   if (CPP_OPTION (pfile, preprocessed))
 615     {
 616       pfile->state.prevent_expansion = 1;
 617       CPP_OPTION (pfile, traditional) = 0;
 618     }
 619
 620   if (CPP_OPTION (pfile, warn_trigraphs) == 2)
 621     CPP_OPTION (pfile, warn_trigraphs) = !CPP_OPTION (pfile, trigraphs);
 622
 623   if (CPP_OPTION (pfile, traditional))
 624     {
 625       CPP_OPTION (pfile, cplusplus_comments) = 0;
 626
 627       /* Traditional CPP does not accurately track column information.  */
 628       CPP_OPTION (pfile, show_column) = 0;
 629       CPP_OPTION (pfile, trigraphs) = 0;
 630       CPP_OPTION (pfile, warn_trigraphs) = 0;
 631     }
 632 }