gcc/c-family/c-ppoutput.c

   1 /* Preprocess only, using cpplib.
   2    Copyright (C) 1995-2015 Free Software Foundation, Inc.
   3    Written by Per Bothner, 1994-95.
   4
   5    This program is free software; you can redistribute it and/or modify it
   6    under the terms of the GNU General Public License as published by the
   7    Free Software Foundation; either version 3, or (at your option) any
   8    later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; see the file COPYING3.  If not see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include "config.h"
  20 #include "system.h"
  21 #include "coretypes.h"
  22 #include "cpplib.h"
  23 #include "../libcpp/internal.h"
  24 #include "alias.h"
  25 #include "tree.h"
  26 #include "options.h"
  27 #include "c-common.h"           /* For flags.  */
  28 #include "c-pragma.h"           /* For parse_in.  */
  29
  30 /* Encapsulates state used to convert a stream of tokens into a text
  31    file.  */
  32 static struct
  33 {
  34   FILE *outf;                   /* Stream to write to.  */
  35   const cpp_token *prev;        /* Previous token.  */
  36   const cpp_token *source;      /* Source token for spacing.  */
  37   int src_line;                 /* Line number currently being written.  */
  38   unsigned char printed;        /* Nonzero if something output at line.  */
  39   bool first_time;              /* pp_file_change hasn't been called yet.  */
  40   const char *src_file;         /* Current source file.  */
  41   bool prev_was_system_token;   /* True if the previous token was a
  42                                    system token.*/
  43 } print;
  44
  45 /* Defined and undefined macros being queued for output with -dU at
  46    the next newline.  */
  47 struct macro_queue
  48 {
  49   struct macro_queue *next;     /* Next macro in the list.  */
  50   char *macro;                  /* The name of the macro if not
  51                                    defined, the full definition if
  52                                    defined.  */
  53 };
  54 static macro_queue *define_queue, *undef_queue;
  55
  56 /* General output routines.  */
  57 static void scan_translation_unit (cpp_reader *);
  58 static void print_lines_directives_only (int, const void *, size_t);
  59 static void scan_translation_unit_directives_only (cpp_reader *);
  60 static void scan_translation_unit_trad (cpp_reader *);
  61 static void account_for_newlines (const unsigned char *, size_t);
  62 static int dump_macro (cpp_reader *, cpp_hashnode *, void *);
  63 static void dump_queued_macros (cpp_reader *);
  64
  65 static bool print_line_1 (source_location, const char*, FILE *);
  66 static bool print_line (source_location, const char *);
  67 static bool maybe_print_line_1 (source_location, FILE *);
  68 static bool maybe_print_line (source_location);
  69 static bool do_line_change (cpp_reader *, const cpp_token *,
  70                             source_location, int);
  71
  72 /* Callback routines for the parser.   Most of these are active only
  73    in specific modes.  */
  74 static void cb_line_change (cpp_reader *, const cpp_token *, int);
  75 static void cb_define (cpp_reader *, source_location, cpp_hashnode *);
  76 static void cb_undef (cpp_reader *, source_location, cpp_hashnode *);
  77 static void cb_used_define (cpp_reader *, source_location, cpp_hashnode *);
  78 static void cb_used_undef (cpp_reader *, source_location, cpp_hashnode *);
  79 static void cb_include (cpp_reader *, source_location, const unsigned char *,
  80                         const char *, int, const cpp_token **);
  81 static void cb_ident (cpp_reader *, source_location, const cpp_string *);
  82 static void cb_def_pragma (cpp_reader *, source_location);
  83 static void cb_read_pch (cpp_reader *pfile, const char *name,
  84                          int fd, const char *orig_name);
  85
  86 /* Preprocess and output.  */
  87 void
  88 preprocess_file (cpp_reader *pfile)
  89 {
  90   /* A successful cpp_read_main_file guarantees that we can call
  91      cpp_scan_nooutput or cpp_get_token next.  */
  92   if (flag_no_output && pfile->buffer)
  93     {
  94       /* Scan -included buffers, then the main file.  */
  95       while (pfile->buffer->prev)
  96         cpp_scan_nooutput (pfile);
  97       cpp_scan_nooutput (pfile);
  98     }
  99   else if (cpp_get_options (pfile)->traditional)
 100     scan_translation_unit_trad (pfile);
 101   else if (cpp_get_options (pfile)->directives_only
 102            && !cpp_get_options (pfile)->preprocessed)
 103     scan_translation_unit_directives_only (pfile);
 104   else
 105     scan_translation_unit (pfile);
 106
 107   /* -dM command line option.  Should this be elsewhere?  */
 108   if (flag_dump_macros == 'M')
 109     cpp_forall_identifiers (pfile, dump_macro, NULL);
 110
 111   /* Flush any pending output.  */
 112   if (print.printed)
 113     putc ('\n', print.outf);
 114 }
 115
 116 /* Set up the callbacks as appropriate.  */
 117 void
 118 init_pp_output (FILE *out_stream)
 119 {
 120   cpp_callbacks *cb = cpp_get_callbacks (parse_in);
 121
 122   if (!flag_no_output)
 123     {
 124       cb->line_change = cb_line_change;
 125       /* Don't emit #pragma or #ident directives if we are processing
 126          assembly language; the assembler may choke on them.  */
 127       if (cpp_get_options (parse_in)->lang != CLK_ASM)
 128         {
 129           cb->ident      = cb_ident;
 130           cb->def_pragma = cb_def_pragma;
 131         }
 132     }
 133
 134   if (flag_dump_includes)
 135     cb->include  = cb_include;
 136
 137   if (flag_pch_preprocess)
 138     {
 139       cb->valid_pch = c_common_valid_pch;
 140       cb->read_pch = cb_read_pch;
 141     }
 142
 143   if (flag_dump_macros == 'N' || flag_dump_macros == 'D')
 144     {
 145       cb->define = cb_define;
 146       cb->undef  = cb_undef;
 147     }
 148
 149   if (flag_dump_macros == 'U')
 150     {
 151       cb->before_define = dump_queued_macros;
 152       cb->used_define = cb_used_define;
 153       cb->used_undef = cb_used_undef;
 154     }
 155
 156   cb->has_attribute = c_common_has_attribute;
 157
 158   /* Initialize the print structure.  */
 159   print.src_line = 1;
 160   print.printed = 0;
 161   print.prev = 0;
 162   print.outf = out_stream;
 163   print.first_time = 1;
 164   print.src_file = "";
 165   print.prev_was_system_token = false;
 166 }
 167
 168 /* Writes out the preprocessed file, handling spacing and paste
 169    avoidance issues.  */
 170 static void
 171 scan_translation_unit (cpp_reader *pfile)
 172 {
 173   bool avoid_paste = false;
 174   bool do_line_adjustments
 175     = cpp_get_options (parse_in)->lang != CLK_ASM
 176       && !flag_no_line_commands;
 177   bool in_pragma = false;
 178   bool line_marker_emitted = false;
 179
 180   print.source = NULL;
 181   for (;;)
 182     {
 183       source_location loc;
 184       const cpp_token *token = cpp_get_token_with_location (pfile, &loc);
 185
 186       if (token->type == CPP_PADDING)
 187         {
 188           avoid_paste = true;
 189           if (print.source == NULL
 190               || (!(print.source->flags & PREV_WHITE)
 191                   && token->val.source == NULL))
 192             print.source = token->val.source;
 193           continue;
 194         }
 195
 196       if (token->type == CPP_EOF)
 197         break;
 198
 199       /* Subtle logic to output a space if and only if necessary.  */
 200       if (avoid_paste)
 201         {
 202           int src_line = LOCATION_LINE (loc);
 203
 204           if (print.source == NULL)
 205             print.source = token;
 206
 207           if (src_line != print.src_line
 208               && do_line_adjustments
 209               && !in_pragma)
 210             {
 211               line_marker_emitted = do_line_change (pfile, token, loc, false);
 212               putc (' ', print.outf);
 213             }
 214           else if (print.source->flags & PREV_WHITE
 215                    || (print.prev
 216                        && cpp_avoid_paste (pfile, print.prev, token))
 217                    || (print.prev == NULL && token->type == CPP_HASH))
 218             putc (' ', print.outf);
 219         }
 220       else if (token->flags & PREV_WHITE)
 221         {
 222           int src_line = LOCATION_LINE (loc);
 223
 224           if (src_line != print.src_line
 225               && do_line_adjustments
 226               && !in_pragma)
 227             line_marker_emitted = do_line_change (pfile, token, loc, false);
 228           putc (' ', print.outf);
 229         }
 230
 231       avoid_paste = false;
 232       print.source = NULL;
 233       print.prev = token;
 234       if (token->type == CPP_PRAGMA)
 235         {
 236           const char *space;
 237           const char *name;
 238
 239           line_marker_emitted = maybe_print_line (token->src_loc);
 240           fputs ("#pragma ", print.outf);
 241           c_pp_lookup_pragma (token->val.pragma, &space, &name);
 242           if (space)
 243             fprintf (print.outf, "%s %s", space, name);
 244           else
 245             fprintf (print.outf, "%s", name);
 246           print.printed = 1;
 247           in_pragma = true;
 248         }
 249       else if (token->type == CPP_PRAGMA_EOL)
 250         {
 251           maybe_print_line (token->src_loc);
 252           in_pragma = false;
 253         }
 254       else
 255         {
 256           if (cpp_get_options (parse_in)->debug)
 257               linemap_dump_location (line_table, token->src_loc,
 258                                      print.outf);
 259
 260           if (do_line_adjustments
 261               && !in_pragma
 262               && !line_marker_emitted
 263               && print.prev_was_system_token != !!in_system_header_at(loc)
 264               && !is_location_from_builtin_token (loc))
 265             /* The system-ness of this token is different from the one
 266                of the previous token.  Let's emit a line change to
 267                mark the new system-ness before we emit the token.  */
 268             {
 269               do_line_change (pfile, token, loc, false);
 270               print.prev_was_system_token = !!in_system_header_at(loc);
 271             }
 272           cpp_output_token (token, print.outf);
 273           line_marker_emitted = false;
 274         }
 275
 276       /* CPP_COMMENT tokens and raw-string literal tokens can
 277          have embedded new-line characters.  Rather than enumerating
 278          all the possible token types just check if token uses
 279          val.str union member.  */
 280       if (cpp_token_val_index (token) == CPP_TOKEN_FLD_STR)
 281         account_for_newlines (token->val.str.text, token->val.str.len);
 282     }
 283 }
 284
 285 static void
 286 print_lines_directives_only (int lines, const void *buf, size_t size)
 287 {
 288   print.src_line += lines;
 289   fwrite (buf, 1, size, print.outf);
 290 }
 291
 292 /* Writes out the preprocessed file, handling spacing and paste
 293    avoidance issues.  */
 294 static void
 295 scan_translation_unit_directives_only (cpp_reader *pfile)
 296 {
 297   struct _cpp_dir_only_callbacks cb;
 298
 299   cb.print_lines = print_lines_directives_only;
 300   cb.maybe_print_line = (void (*) (source_location)) maybe_print_line;
 301
 302   _cpp_preprocess_dir_only (pfile, &cb);
 303 }
 304
 305 /* Adjust print.src_line for newlines embedded in output.  */
 306 static void
 307 account_for_newlines (const unsigned char *str, size_t len)
 308 {
 309   while (len--)
 310     if (*str++ == '\n')
 311       print.src_line++;
 312 }
 313
 314 /* Writes out a traditionally preprocessed file.  */
 315 static void
 316 scan_translation_unit_trad (cpp_reader *pfile)
 317 {
 318   while (_cpp_read_logical_line_trad (pfile))
 319     {
 320       size_t len = pfile->out.cur - pfile->out.base;
 321       maybe_print_line (pfile->out.first_line);
 322       fwrite (pfile->out.base, 1, len, print.outf);
 323       print.printed = 1;
 324       if (!CPP_OPTION (pfile, discard_comments))
 325         account_for_newlines (pfile->out.base, len);
 326     }
 327 }
 328
 329 /* If the token read on logical line LINE needs to be output on a
 330    different line to the current one, output the required newlines or
 331    a line marker.  If a line marker was emitted, return TRUE otherwise
 332    return FALSE.  */
 333
 334 static bool
 335 maybe_print_line_1 (source_location src_loc, FILE *stream)
 336 {
 337   bool emitted_line_marker = false;
 338   int src_line = LOCATION_LINE (src_loc);
 339   const char *src_file = LOCATION_FILE (src_loc);
 340
 341   /* End the previous line of text.  */
 342   if (print.printed)
 343     {
 344       putc ('\n', stream);
 345       print.src_line++;
 346       print.printed = 0;
 347     }
 348
 349   if (!flag_no_line_commands
 350       && src_line >= print.src_line
 351       && src_line < print.src_line + 8
 352       && strcmp (src_file, print.src_file) == 0)
 353     {
 354       while (src_line > print.src_line)
 355         {
 356           putc ('\n', stream);
 357           print.src_line++;
 358         }
 359     }
 360   else
 361     emitted_line_marker = print_line_1 (src_loc, "", stream);
 362
 363   return emitted_line_marker;
 364 }
 365
 366 /* If the token read on logical line LINE needs to be output on a
 367    different line to the current one, output the required newlines or
 368    a line marker.  If a line marker was emitted, return TRUE otherwise
 369    return FALSE.  */
 370
 371 static bool
 372 maybe_print_line (source_location src_loc)
 373 {
 374   if (cpp_get_options (parse_in)->debug)
 375     linemap_dump_location (line_table, src_loc,
 376                            print.outf);
 377   return maybe_print_line_1 (src_loc, print.outf);
 378 }
 379
 380 /* Output a line marker for logical line LINE.  Special flags are "1"
 381    or "2" indicating entering or leaving a file.  If the line marker
 382    was effectively emitted, return TRUE otherwise return FALSE.  */
 383
 384 static bool
 385 print_line_1 (source_location src_loc, const char *special_flags, FILE *stream)
 386 {
 387   bool emitted_line_marker = false;
 388
 389   /* End any previous line of text.  */
 390   if (print.printed)
 391     putc ('\n', stream);
 392   print.printed = 0;
 393
 394   if (!flag_no_line_commands)
 395     {
 396       const char *file_path = LOCATION_FILE (src_loc);
 397       int sysp;
 398       size_t to_file_len = strlen (file_path);
 399       unsigned char *to_file_quoted =
 400          (unsigned char *) alloca (to_file_len * 4 + 1);
 401       unsigned char *p;
 402
 403       print.src_line = LOCATION_LINE (src_loc);
 404       print.src_file = file_path;
 405
 406       /* cpp_quote_string does not nul-terminate, so we have to do it
 407          ourselves.  */
 408       p = cpp_quote_string (to_file_quoted,
 409                             (const unsigned char *) file_path,
 410                             to_file_len);
 411       *p = '\0';
 412       fprintf (stream, "# %u \"%s\"%s",
 413                print.src_line == 0 ? 1 : print.src_line,
 414                to_file_quoted, special_flags);
 415
 416       sysp = in_system_header_at (src_loc);
 417       if (sysp == 2)
 418         fputs (" 3 4", stream);
 419       else if (sysp == 1)
 420         fputs (" 3", stream);
 421
 422       putc ('\n', stream);
 423       emitted_line_marker = true;
 424     }
 425
 426   return emitted_line_marker;
 427 }
 428
 429 /* Output a line marker for logical line LINE.  Special flags are "1"
 430    or "2" indicating entering or leaving a file.  Return TRUE if a
 431    line marker was effectively emitted, FALSE otherwise.  */
 432
 433 static bool
 434 print_line (source_location src_loc, const char *special_flags)
 435 {
 436     if (cpp_get_options (parse_in)->debug)
 437       linemap_dump_location (line_table, src_loc,
 438                              print.outf);
 439     return print_line_1 (src_loc, special_flags, print.outf);
 440 }
 441
 442 /* Helper function for cb_line_change and scan_translation_unit.
 443    Return TRUE if a line marker is emitted, FALSE otherwise.  */
 444 static bool
 445 do_line_change (cpp_reader *pfile, const cpp_token *token,
 446                 source_location src_loc, int parsing_args)
 447 {
 448   bool emitted_line_marker = false;
 449   if (define_queue || undef_queue)
 450     dump_queued_macros (pfile);
 451
 452   if (token->type == CPP_EOF || parsing_args)
 453     return false;
 454
 455   emitted_line_marker = maybe_print_line (src_loc);
 456   print.prev = 0;
 457   print.source = 0;
 458
 459   /* Supply enough spaces to put this token in its original column,
 460      one space per column greater than 2, since scan_translation_unit
 461      will provide a space if PREV_WHITE.  Don't bother trying to
 462      reconstruct tabs; we can't get it right in general, and nothing
 463      ought to care.  Some things do care; the fault lies with them.  */
 464   if (!CPP_OPTION (pfile, traditional))
 465     {
 466       int spaces = LOCATION_COLUMN (src_loc) - 2;
 467       print.printed = 1;
 468
 469       while (-- spaces >= 0)
 470         putc (' ', print.outf);
 471     }
 472
 473   return emitted_line_marker;
 474 }
 475
 476 /* Called when a line of output is started.  TOKEN is the first token
 477    of the line, and at end of file will be CPP_EOF.  */
 478 static void
 479 cb_line_change (cpp_reader *pfile, const cpp_token *token,
 480                 int parsing_args)
 481 {
 482   do_line_change (pfile, token, token->src_loc, parsing_args);
 483 }
 484
 485 static void
 486 cb_ident (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
 487           const cpp_string *str)
 488 {
 489   maybe_print_line (line);
 490   fprintf (print.outf, "#ident %s\n", str->text);
 491   print.src_line++;
 492 }
 493
 494 static void
 495 cb_define (cpp_reader *pfile, source_location line, cpp_hashnode *node)
 496 {
 497   const line_map_ordinary *map;
 498
 499   maybe_print_line (line);
 500   fputs ("#define ", print.outf);
 501
 502   /* 'D' is whole definition; 'N' is name only.  */
 503   if (flag_dump_macros == 'D')
 504     fputs ((const char *) cpp_macro_definition (pfile, node),
 505            print.outf);
 506   else
 507     fputs ((const char *) NODE_NAME (node), print.outf);
 508
 509   putc ('\n', print.outf);
 510   linemap_resolve_location (line_table, line,
 511                             LRK_MACRO_DEFINITION_LOCATION,
 512                             &map);
 513   if (LINEMAP_LINE (map) != 0)
 514     print.src_line++;
 515 }
 516
 517 static void
 518 cb_undef (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
 519           cpp_hashnode *node)
 520 {
 521   maybe_print_line (line);
 522   fprintf (print.outf, "#undef %s\n", NODE_NAME (node));
 523   print.src_line++;
 524 }
 525
 526 static void
 527 cb_used_define (cpp_reader *pfile, source_location line ATTRIBUTE_UNUSED,
 528                 cpp_hashnode *node)
 529 {
 530   macro_queue *q;
 531   if (node->flags & NODE_BUILTIN)
 532     return;
 533   q = XNEW (macro_queue);
 534   q->macro = xstrdup ((const char *) cpp_macro_definition (pfile, node));
 535   q->next = define_queue;
 536   define_queue = q;
 537 }
 538
 539 static void
 540 cb_used_undef (cpp_reader *pfile ATTRIBUTE_UNUSED,
 541                source_location line ATTRIBUTE_UNUSED,
 542                cpp_hashnode *node)
 543 {
 544   macro_queue *q;
 545   q = XNEW (macro_queue);
 546   q->macro = xstrdup ((const char *) NODE_NAME (node));
 547   q->next = undef_queue;
 548   undef_queue = q;
 549 }
 550
 551 static void
 552 dump_queued_macros (cpp_reader *pfile ATTRIBUTE_UNUSED)
 553 {
 554   macro_queue *q;
 555
 556   /* End the previous line of text.  */
 557   if (print.printed)
 558     {
 559       putc ('\n', print.outf);
 560       print.src_line++;
 561       print.printed = 0;
 562     }
 563
 564   for (q = define_queue; q;)
 565     {
 566       macro_queue *oq;
 567       fputs ("#define ", print.outf);
 568       fputs (q->macro, print.outf);
 569       putc ('\n', print.outf);
 570       print.src_line++;
 571       oq = q;
 572       q = q->next;
 573       free (oq->macro);
 574       free (oq);
 575     }
 576   define_queue = NULL;
 577   for (q = undef_queue; q;)
 578     {
 579       macro_queue *oq;
 580       fprintf (print.outf, "#undef %s\n", q->macro);
 581       print.src_line++;
 582       oq = q;
 583       q = q->next;
 584       free (oq->macro);
 585       free (oq);
 586     }
 587   undef_queue = NULL;
 588 }
 589
 590 static void
 591 cb_include (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
 592             const unsigned char *dir, const char *header, int angle_brackets,
 593             const cpp_token **comments)
 594 {
 595   maybe_print_line (line);
 596   if (angle_brackets)
 597     fprintf (print.outf, "#%s <%s>", dir, header);
 598   else
 599     fprintf (print.outf, "#%s \"%s\"", dir, header);
 600
 601   if (comments != NULL)
 602     {
 603       while (*comments != NULL)
 604         {
 605           if ((*comments)->flags & PREV_WHITE)
 606             putc (' ', print.outf);
 607           cpp_output_token (*comments, print.outf);
 608           ++comments;
 609         }
 610     }
 611
 612   putc ('\n', print.outf);
 613   print.src_line++;
 614 }
 615
 616 /* Callback called when -fworking-director and -E to emit working
 617    directory in cpp output file.  */
 618
 619 void
 620 pp_dir_change (cpp_reader *pfile ATTRIBUTE_UNUSED, const char *dir)
 621 {
 622   size_t to_file_len = strlen (dir);
 623   unsigned char *to_file_quoted =
 624      (unsigned char *) alloca (to_file_len * 4 + 1);
 625   unsigned char *p;
 626
 627   /* cpp_quote_string does not nul-terminate, so we have to do it ourselves.  */
 628   p = cpp_quote_string (to_file_quoted, (const unsigned char *) dir, to_file_len);
 629   *p = '\0';
 630   fprintf (print.outf, "# 1 \"%s//\"\n", to_file_quoted);
 631 }
 632
 633 /* The file name, line number or system header flags have changed, as
 634    described in MAP.  */
 635
 636 void
 637 pp_file_change (const line_map_ordinary *map)
 638 {
 639   const char *flags = "";
 640
 641   if (flag_no_line_commands)
 642     return;
 643
 644   if (map != NULL)
 645     {
 646       input_location = map->start_location;
 647       if (print.first_time)
 648         {
 649           /* Avoid printing foo.i when the main file is foo.c.  */
 650           if (!cpp_get_options (parse_in)->preprocessed)
 651             print_line (map->start_location, flags);
 652           print.first_time = 0;
 653         }
 654       else
 655         {
 656           /* Bring current file to correct line when entering a new file.  */
 657           if (map->reason == LC_ENTER)
 658             {
 659               const line_map_ordinary *from = INCLUDED_FROM (line_table, map);
 660               maybe_print_line (LAST_SOURCE_LINE_LOCATION (from));
 661             }
 662           if (map->reason == LC_ENTER)
 663             flags = " 1";
 664           else if (map->reason == LC_LEAVE)
 665             flags = " 2";
 666           print_line (map->start_location, flags);
 667         }
 668     }
 669 }
 670
 671 /* Copy a #pragma directive to the preprocessed output.  */
 672 static void
 673 cb_def_pragma (cpp_reader *pfile, source_location line)
 674 {
 675   maybe_print_line (line);
 676   fputs ("#pragma ", print.outf);
 677   cpp_output_line (pfile, print.outf);
 678   print.src_line++;
 679 }
 680
 681 /* Dump out the hash table.  */
 682 static int
 683 dump_macro (cpp_reader *pfile, cpp_hashnode *node, void *v ATTRIBUTE_UNUSED)
 684 {
 685   if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
 686     {
 687       fputs ("#define ", print.outf);
 688       fputs ((const char *) cpp_macro_definition (pfile, node),
 689              print.outf);
 690       putc ('\n', print.outf);
 691       print.src_line++;
 692     }
 693
 694   return 1;
 695 }
 696
 697 /* Load in the PCH file NAME, open on FD.  It was originally searched for
 698    by ORIG_NAME.  Also, print out a #include command so that the PCH
 699    file can be loaded when the preprocessed output is compiled.  */
 700
 701 static void
 702 cb_read_pch (cpp_reader *pfile, const char *name,
 703              int fd, const char *orig_name ATTRIBUTE_UNUSED)
 704 {
 705   c_common_read_pch (pfile, name, fd, orig_name);
 706
 707   fprintf (print.outf, "#pragma GCC pch_preprocess \"%s\"\n", name);
 708   print.src_line++;
 709 }