c-lex.c revision 96263
1/* Lexical analyzer for C and Objective C.
2   Copyright (C) 1987, 1988, 1989, 1992, 1994, 1995, 1996, 1997
3   1998, 1999, 2000 Free Software Foundation, Inc.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 2, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING.  If not, write to the Free
19Software Foundation, 59 Temple Place - Suite 330, Boston, MA
2002111-1307, USA.  */
21
22#include "config.h"
23#include "system.h"
24
25#include "rtl.h"
26#include "tree.h"
27#include "expr.h"
28#include "input.h"
29#include "output.h"
30#include "c-lex.h"
31#include "c-tree.h"
32#include "flags.h"
33#include "timevar.h"
34#include "cpplib.h"
35#include "c-pragma.h"
36#include "toplev.h"
37#include "intl.h"
38#include "tm_p.h"
39#include "splay-tree.h"
40#include "debug.h"
41
42/* MULTIBYTE_CHARS support only works for native compilers.
43   ??? Ideally what we want is to model widechar support after
44   the current floating point support.  */
45#ifdef CROSS_COMPILE
46#undef MULTIBYTE_CHARS
47#endif
48
49#ifdef MULTIBYTE_CHARS
50#include "mbchar.h"
51#include <locale.h>
52#endif /* MULTIBYTE_CHARS */
53#ifndef GET_ENVIRONMENT
54#define GET_ENVIRONMENT(ENV_VALUE,ENV_NAME) ((ENV_VALUE) = getenv (ENV_NAME))
55#endif
56
57/* The current line map.  */
58static const struct line_map *map;
59
60/* The line used to refresh the lineno global variable after each token.  */
61static unsigned int src_lineno;
62
63/* We may keep statistics about how long which files took to compile.  */
64static int header_time, body_time;
65static splay_tree file_info_tree;
66
67/* Cause the `yydebug' variable to be defined.  */
68#define YYDEBUG 1
69
70/* File used for outputting assembler code.  */
71extern FILE *asm_out_file;
72
73#undef WCHAR_TYPE_SIZE
74#define WCHAR_TYPE_SIZE TYPE_PRECISION (wchar_type_node)
75
76/* Number of bytes in a wide character.  */
77#define WCHAR_BYTES (WCHAR_TYPE_SIZE / BITS_PER_UNIT)
78
79int indent_level;        /* Number of { minus number of }.  */
80int pending_lang_change; /* If we need to switch languages - C++ only */
81int c_header_level;	 /* depth in C headers - C++ only */
82
83/* Nonzero tells yylex to ignore \ in string constants.  */
84static int ignore_escape_flag;
85
86static void parse_float		PARAMS ((PTR));
87static tree lex_number		PARAMS ((const char *, unsigned int));
88static tree lex_string		PARAMS ((const unsigned char *, unsigned int,
89					 int));
90static tree lex_charconst	PARAMS ((const cpp_token *));
91static void update_header_times	PARAMS ((const char *));
92static int dump_one_header	PARAMS ((splay_tree_node, void *));
93static void cb_line_change     PARAMS ((cpp_reader *, const cpp_token *, int));
94static void cb_ident		PARAMS ((cpp_reader *, unsigned int,
95					 const cpp_string *));
96static void cb_file_change    PARAMS ((cpp_reader *, const struct line_map *));
97static void cb_def_pragma	PARAMS ((cpp_reader *, unsigned int));
98static void cb_define		PARAMS ((cpp_reader *, unsigned int,
99					 cpp_hashnode *));
100static void cb_undef		PARAMS ((cpp_reader *, unsigned int,
101					 cpp_hashnode *));
102
103const char *
104init_c_lex (filename)
105     const char *filename;
106{
107  struct cpp_callbacks *cb;
108  struct c_fileinfo *toplevel;
109
110  /* Set up filename timing.  Must happen before cpp_read_main_file.  */
111  file_info_tree = splay_tree_new ((splay_tree_compare_fn)strcmp,
112				   0,
113				   (splay_tree_delete_value_fn)free);
114  toplevel = get_fileinfo ("<top level>");
115  if (flag_detailed_statistics)
116    {
117      header_time = 0;
118      body_time = get_run_time ();
119      toplevel->time = body_time;
120    }
121
122#ifdef MULTIBYTE_CHARS
123  /* Change to the native locale for multibyte conversions.  */
124  setlocale (LC_CTYPE, "");
125  GET_ENVIRONMENT (literal_codeset, "LANG");
126#endif
127
128  cb = cpp_get_callbacks (parse_in);
129
130  cb->line_change = cb_line_change;
131  cb->ident = cb_ident;
132  cb->file_change = cb_file_change;
133  cb->def_pragma = cb_def_pragma;
134
135  /* Set the debug callbacks if we can use them.  */
136  if (debug_info_level == DINFO_LEVEL_VERBOSE
137      && (write_symbols == DWARF_DEBUG || write_symbols == DWARF2_DEBUG
138          || write_symbols == VMS_AND_DWARF2_DEBUG))
139    {
140      cb->define = cb_define;
141      cb->undef = cb_undef;
142    }
143
144  /* Start it at 0.  */
145  lineno = 0;
146
147  if (filename == NULL || !strcmp (filename, "-"))
148    filename = "";
149
150  return cpp_read_main_file (parse_in, filename, ident_hash);
151}
152
153/* A thin wrapper around the real parser that initializes the
154   integrated preprocessor after debug output has been initialized.
155   Also, make sure the start_source_file debug hook gets called for
156   the primary source file.  */
157
158int
159yyparse()
160{
161  (*debug_hooks->start_source_file) (lineno, input_filename);
162  cpp_finish_options (parse_in);
163
164  return yyparse_1();
165}
166
167struct c_fileinfo *
168get_fileinfo (name)
169     const char *name;
170{
171  splay_tree_node n;
172  struct c_fileinfo *fi;
173
174  n = splay_tree_lookup (file_info_tree, (splay_tree_key) name);
175  if (n)
176    return (struct c_fileinfo *) n->value;
177
178  fi = (struct c_fileinfo *) xmalloc (sizeof (struct c_fileinfo));
179  fi->time = 0;
180  fi->interface_only = 0;
181  fi->interface_unknown = 1;
182  splay_tree_insert (file_info_tree, (splay_tree_key) name,
183		     (splay_tree_value) fi);
184  return fi;
185}
186
187static void
188update_header_times (name)
189     const char *name;
190{
191  /* Changing files again.  This means currently collected time
192     is charged against header time, and body time starts back at 0.  */
193  if (flag_detailed_statistics)
194    {
195      int this_time = get_run_time ();
196      struct c_fileinfo *file = get_fileinfo (name);
197      header_time += this_time - body_time;
198      file->time += this_time - body_time;
199      body_time = this_time;
200    }
201}
202
203static int
204dump_one_header (n, dummy)
205     splay_tree_node n;
206     void *dummy ATTRIBUTE_UNUSED;
207{
208  print_time ((const char *) n->key,
209	      ((struct c_fileinfo *) n->value)->time);
210  return 0;
211}
212
213void
214dump_time_statistics ()
215{
216  struct c_fileinfo *file = get_fileinfo (input_filename);
217  int this_time = get_run_time ();
218  file->time += this_time - body_time;
219
220  fprintf (stderr, "\n******\n");
221  print_time ("header files (total)", header_time);
222  print_time ("main file (total)", this_time - body_time);
223  fprintf (stderr, "ratio = %g : 1\n",
224	   (double)header_time / (double)(this_time - body_time));
225  fprintf (stderr, "\n******\n");
226
227  splay_tree_foreach (file_info_tree, dump_one_header, 0);
228}
229
230/* Not yet handled: #pragma, #define, #undef.
231   No need to deal with linemarkers under normal conditions.  */
232
233static void
234cb_ident (pfile, line, str)
235     cpp_reader *pfile ATTRIBUTE_UNUSED;
236     unsigned int line ATTRIBUTE_UNUSED;
237     const cpp_string *str ATTRIBUTE_UNUSED;
238{
239#ifdef ASM_OUTPUT_IDENT
240  if (! flag_no_ident)
241    {
242      /* Convert escapes in the string.  */
243      tree value = lex_string (str->text, str->len, 0);
244      ASM_OUTPUT_IDENT (asm_out_file, TREE_STRING_POINTER (value));
245    }
246#endif
247}
248
249/* Called at the start of every non-empty line.  TOKEN is the first
250   lexed token on the line.  Used for diagnostic line numbers.  */
251static void
252cb_line_change (pfile, token, parsing_args)
253     cpp_reader *pfile ATTRIBUTE_UNUSED;
254     const cpp_token *token;
255     int parsing_args ATTRIBUTE_UNUSED;
256{
257  src_lineno = SOURCE_LINE (map, token->line);
258}
259
260static void
261cb_file_change (pfile, new_map)
262     cpp_reader *pfile ATTRIBUTE_UNUSED;
263     const struct line_map *new_map;
264{
265  unsigned int to_line = SOURCE_LINE (new_map, new_map->to_line);
266
267  if (new_map->reason == LC_ENTER)
268    {
269      /* Don't stack the main buffer on the input stack;
270	 we already did in compile_file.  */
271      if (map == NULL)
272	main_input_filename = new_map->to_file;
273      else
274	{
275          int included_at = SOURCE_LINE (new_map - 1, new_map->from_line - 1);
276
277	  lineno = included_at;
278	  push_srcloc (new_map->to_file, 1);
279	  input_file_stack->indent_level = indent_level;
280	  (*debug_hooks->start_source_file) (included_at, new_map->to_file);
281#ifndef NO_IMPLICIT_EXTERN_C
282	  if (c_header_level)
283	    ++c_header_level;
284	  else if (new_map->sysp == 2)
285	    {
286	      c_header_level = 1;
287	      ++pending_lang_change;
288	    }
289#endif
290	}
291    }
292  else if (new_map->reason == LC_LEAVE)
293    {
294#ifndef NO_IMPLICIT_EXTERN_C
295      if (c_header_level && --c_header_level == 0)
296	{
297	  if (new_map->sysp == 2)
298	    warning ("badly nested C headers from preprocessor");
299	  --pending_lang_change;
300	}
301#endif
302#if 0
303      if (indent_level != input_file_stack->indent_level)
304	{
305	  warning_with_file_and_line
306	    (input_filename, lineno,
307	     "this file contains more '%c's than '%c's",
308	     indent_level > input_file_stack->indent_level ? '{' : '}',
309	     indent_level > input_file_stack->indent_level ? '}' : '{');
310	}
311#endif
312      pop_srcloc ();
313
314      (*debug_hooks->end_source_file) (to_line);
315    }
316
317  update_header_times (new_map->to_file);
318  in_system_header = new_map->sysp != 0;
319  input_filename = new_map->to_file;
320  lineno = to_line;
321  map = new_map;
322
323  /* Hook for C++.  */
324  extract_interface_info ();
325}
326
327static void
328cb_def_pragma (pfile, line)
329     cpp_reader *pfile;
330     unsigned int line;
331{
332  /* Issue a warning message if we have been asked to do so.  Ignore
333     unknown pragmas in system headers unless an explicit
334     -Wunknown-pragmas has been given.  */
335  if (warn_unknown_pragmas > in_system_header)
336    {
337      const unsigned char *space, *name = 0;
338      const cpp_token *s;
339
340      s = cpp_get_token (pfile);
341      space = cpp_token_as_text (pfile, s);
342      s = cpp_get_token (pfile);
343      if (s->type == CPP_NAME)
344	name = cpp_token_as_text (pfile, s);
345
346      lineno = SOURCE_LINE (map, line);
347      if (name)
348	warning ("ignoring #pragma %s %s", space, name);
349      else
350	warning ("ignoring #pragma %s", space);
351    }
352}
353
354/* #define callback for DWARF and DWARF2 debug info.  */
355static void
356cb_define (pfile, line, node)
357     cpp_reader *pfile;
358     unsigned int line;
359     cpp_hashnode *node;
360{
361  (*debug_hooks->define) (SOURCE_LINE (map, line),
362			  (const char *) cpp_macro_definition (pfile, node));
363}
364
365/* #undef callback for DWARF and DWARF2 debug info.  */
366static void
367cb_undef (pfile, line, node)
368     cpp_reader *pfile ATTRIBUTE_UNUSED;
369     unsigned int line;
370     cpp_hashnode *node;
371{
372  (*debug_hooks->undef) (SOURCE_LINE (map, line),
373			 (const char *) NODE_NAME (node));
374}
375
376#if 0 /* not yet */
377/* Returns nonzero if C is a universal-character-name.  Give an error if it
378   is not one which may appear in an identifier, as per [extendid].
379
380   Note that extended character support in identifiers has not yet been
381   implemented.  It is my personal opinion that this is not a desirable
382   feature.  Portable code cannot count on support for more than the basic
383   identifier character set.  */
384
385static inline int
386is_extended_char (c)
387     int c;
388{
389#ifdef TARGET_EBCDIC
390  return 0;
391#else
392  /* ASCII.  */
393  if (c < 0x7f)
394    return 0;
395
396  /* None of the valid chars are outside the Basic Multilingual Plane (the
397     low 16 bits).  */
398  if (c > 0xffff)
399    {
400      error ("universal-character-name '\\U%08x' not valid in identifier", c);
401      return 1;
402    }
403
404  /* Latin */
405  if ((c >= 0x00c0 && c <= 0x00d6)
406      || (c >= 0x00d8 && c <= 0x00f6)
407      || (c >= 0x00f8 && c <= 0x01f5)
408      || (c >= 0x01fa && c <= 0x0217)
409      || (c >= 0x0250 && c <= 0x02a8)
410      || (c >= 0x1e00 && c <= 0x1e9a)
411      || (c >= 0x1ea0 && c <= 0x1ef9))
412    return 1;
413
414  /* Greek */
415  if ((c == 0x0384)
416      || (c >= 0x0388 && c <= 0x038a)
417      || (c == 0x038c)
418      || (c >= 0x038e && c <= 0x03a1)
419      || (c >= 0x03a3 && c <= 0x03ce)
420      || (c >= 0x03d0 && c <= 0x03d6)
421      || (c == 0x03da)
422      || (c == 0x03dc)
423      || (c == 0x03de)
424      || (c == 0x03e0)
425      || (c >= 0x03e2 && c <= 0x03f3)
426      || (c >= 0x1f00 && c <= 0x1f15)
427      || (c >= 0x1f18 && c <= 0x1f1d)
428      || (c >= 0x1f20 && c <= 0x1f45)
429      || (c >= 0x1f48 && c <= 0x1f4d)
430      || (c >= 0x1f50 && c <= 0x1f57)
431      || (c == 0x1f59)
432      || (c == 0x1f5b)
433      || (c == 0x1f5d)
434      || (c >= 0x1f5f && c <= 0x1f7d)
435      || (c >= 0x1f80 && c <= 0x1fb4)
436      || (c >= 0x1fb6 && c <= 0x1fbc)
437      || (c >= 0x1fc2 && c <= 0x1fc4)
438      || (c >= 0x1fc6 && c <= 0x1fcc)
439      || (c >= 0x1fd0 && c <= 0x1fd3)
440      || (c >= 0x1fd6 && c <= 0x1fdb)
441      || (c >= 0x1fe0 && c <= 0x1fec)
442      || (c >= 0x1ff2 && c <= 0x1ff4)
443      || (c >= 0x1ff6 && c <= 0x1ffc))
444    return 1;
445
446  /* Cyrillic */
447  if ((c >= 0x0401 && c <= 0x040d)
448      || (c >= 0x040f && c <= 0x044f)
449      || (c >= 0x0451 && c <= 0x045c)
450      || (c >= 0x045e && c <= 0x0481)
451      || (c >= 0x0490 && c <= 0x04c4)
452      || (c >= 0x04c7 && c <= 0x04c8)
453      || (c >= 0x04cb && c <= 0x04cc)
454      || (c >= 0x04d0 && c <= 0x04eb)
455      || (c >= 0x04ee && c <= 0x04f5)
456      || (c >= 0x04f8 && c <= 0x04f9))
457    return 1;
458
459  /* Armenian */
460  if ((c >= 0x0531 && c <= 0x0556)
461      || (c >= 0x0561 && c <= 0x0587))
462    return 1;
463
464  /* Hebrew */
465  if ((c >= 0x05d0 && c <= 0x05ea)
466      || (c >= 0x05f0 && c <= 0x05f4))
467    return 1;
468
469  /* Arabic */
470  if ((c >= 0x0621 && c <= 0x063a)
471      || (c >= 0x0640 && c <= 0x0652)
472      || (c >= 0x0670 && c <= 0x06b7)
473      || (c >= 0x06ba && c <= 0x06be)
474      || (c >= 0x06c0 && c <= 0x06ce)
475      || (c >= 0x06e5 && c <= 0x06e7))
476    return 1;
477
478  /* Devanagari */
479  if ((c >= 0x0905 && c <= 0x0939)
480      || (c >= 0x0958 && c <= 0x0962))
481    return 1;
482
483  /* Bengali */
484  if ((c >= 0x0985 && c <= 0x098c)
485      || (c >= 0x098f && c <= 0x0990)
486      || (c >= 0x0993 && c <= 0x09a8)
487      || (c >= 0x09aa && c <= 0x09b0)
488      || (c == 0x09b2)
489      || (c >= 0x09b6 && c <= 0x09b9)
490      || (c >= 0x09dc && c <= 0x09dd)
491      || (c >= 0x09df && c <= 0x09e1)
492      || (c >= 0x09f0 && c <= 0x09f1))
493    return 1;
494
495  /* Gurmukhi */
496  if ((c >= 0x0a05 && c <= 0x0a0a)
497      || (c >= 0x0a0f && c <= 0x0a10)
498      || (c >= 0x0a13 && c <= 0x0a28)
499      || (c >= 0x0a2a && c <= 0x0a30)
500      || (c >= 0x0a32 && c <= 0x0a33)
501      || (c >= 0x0a35 && c <= 0x0a36)
502      || (c >= 0x0a38 && c <= 0x0a39)
503      || (c >= 0x0a59 && c <= 0x0a5c)
504      || (c == 0x0a5e))
505    return 1;
506
507  /* Gujarati */
508  if ((c >= 0x0a85 && c <= 0x0a8b)
509      || (c == 0x0a8d)
510      || (c >= 0x0a8f && c <= 0x0a91)
511      || (c >= 0x0a93 && c <= 0x0aa8)
512      || (c >= 0x0aaa && c <= 0x0ab0)
513      || (c >= 0x0ab2 && c <= 0x0ab3)
514      || (c >= 0x0ab5 && c <= 0x0ab9)
515      || (c == 0x0ae0))
516    return 1;
517
518  /* Oriya */
519  if ((c >= 0x0b05 && c <= 0x0b0c)
520      || (c >= 0x0b0f && c <= 0x0b10)
521      || (c >= 0x0b13 && c <= 0x0b28)
522      || (c >= 0x0b2a && c <= 0x0b30)
523      || (c >= 0x0b32 && c <= 0x0b33)
524      || (c >= 0x0b36 && c <= 0x0b39)
525      || (c >= 0x0b5c && c <= 0x0b5d)
526      || (c >= 0x0b5f && c <= 0x0b61))
527    return 1;
528
529  /* Tamil */
530  if ((c >= 0x0b85 && c <= 0x0b8a)
531      || (c >= 0x0b8e && c <= 0x0b90)
532      || (c >= 0x0b92 && c <= 0x0b95)
533      || (c >= 0x0b99 && c <= 0x0b9a)
534      || (c == 0x0b9c)
535      || (c >= 0x0b9e && c <= 0x0b9f)
536      || (c >= 0x0ba3 && c <= 0x0ba4)
537      || (c >= 0x0ba8 && c <= 0x0baa)
538      || (c >= 0x0bae && c <= 0x0bb5)
539      || (c >= 0x0bb7 && c <= 0x0bb9))
540    return 1;
541
542  /* Telugu */
543  if ((c >= 0x0c05 && c <= 0x0c0c)
544      || (c >= 0x0c0e && c <= 0x0c10)
545      || (c >= 0x0c12 && c <= 0x0c28)
546      || (c >= 0x0c2a && c <= 0x0c33)
547      || (c >= 0x0c35 && c <= 0x0c39)
548      || (c >= 0x0c60 && c <= 0x0c61))
549    return 1;
550
551  /* Kannada */
552  if ((c >= 0x0c85 && c <= 0x0c8c)
553      || (c >= 0x0c8e && c <= 0x0c90)
554      || (c >= 0x0c92 && c <= 0x0ca8)
555      || (c >= 0x0caa && c <= 0x0cb3)
556      || (c >= 0x0cb5 && c <= 0x0cb9)
557      || (c >= 0x0ce0 && c <= 0x0ce1))
558    return 1;
559
560  /* Malayalam */
561  if ((c >= 0x0d05 && c <= 0x0d0c)
562      || (c >= 0x0d0e && c <= 0x0d10)
563      || (c >= 0x0d12 && c <= 0x0d28)
564      || (c >= 0x0d2a && c <= 0x0d39)
565      || (c >= 0x0d60 && c <= 0x0d61))
566    return 1;
567
568  /* Thai */
569  if ((c >= 0x0e01 && c <= 0x0e30)
570      || (c >= 0x0e32 && c <= 0x0e33)
571      || (c >= 0x0e40 && c <= 0x0e46)
572      || (c >= 0x0e4f && c <= 0x0e5b))
573    return 1;
574
575  /* Lao */
576  if ((c >= 0x0e81 && c <= 0x0e82)
577      || (c == 0x0e84)
578      || (c == 0x0e87)
579      || (c == 0x0e88)
580      || (c == 0x0e8a)
581      || (c == 0x0e0d)
582      || (c >= 0x0e94 && c <= 0x0e97)
583      || (c >= 0x0e99 && c <= 0x0e9f)
584      || (c >= 0x0ea1 && c <= 0x0ea3)
585      || (c == 0x0ea5)
586      || (c == 0x0ea7)
587      || (c == 0x0eaa)
588      || (c == 0x0eab)
589      || (c >= 0x0ead && c <= 0x0eb0)
590      || (c == 0x0eb2)
591      || (c == 0x0eb3)
592      || (c == 0x0ebd)
593      || (c >= 0x0ec0 && c <= 0x0ec4)
594      || (c == 0x0ec6))
595    return 1;
596
597  /* Georgian */
598  if ((c >= 0x10a0 && c <= 0x10c5)
599      || (c >= 0x10d0 && c <= 0x10f6))
600    return 1;
601
602  /* Hiragana */
603  if ((c >= 0x3041 && c <= 0x3094)
604      || (c >= 0x309b && c <= 0x309e))
605    return 1;
606
607  /* Katakana */
608  if ((c >= 0x30a1 && c <= 0x30fe))
609    return 1;
610
611  /* Bopmofo */
612  if ((c >= 0x3105 && c <= 0x312c))
613    return 1;
614
615  /* Hangul */
616  if ((c >= 0x1100 && c <= 0x1159)
617      || (c >= 0x1161 && c <= 0x11a2)
618      || (c >= 0x11a8 && c <= 0x11f9))
619    return 1;
620
621  /* CJK Unified Ideographs */
622  if ((c >= 0xf900 && c <= 0xfa2d)
623      || (c >= 0xfb1f && c <= 0xfb36)
624      || (c >= 0xfb38 && c <= 0xfb3c)
625      || (c == 0xfb3e)
626      || (c >= 0xfb40 && c <= 0xfb41)
627      || (c >= 0xfb42 && c <= 0xfb44)
628      || (c >= 0xfb46 && c <= 0xfbb1)
629      || (c >= 0xfbd3 && c <= 0xfd3f)
630      || (c >= 0xfd50 && c <= 0xfd8f)
631      || (c >= 0xfd92 && c <= 0xfdc7)
632      || (c >= 0xfdf0 && c <= 0xfdfb)
633      || (c >= 0xfe70 && c <= 0xfe72)
634      || (c == 0xfe74)
635      || (c >= 0xfe76 && c <= 0xfefc)
636      || (c >= 0xff21 && c <= 0xff3a)
637      || (c >= 0xff41 && c <= 0xff5a)
638      || (c >= 0xff66 && c <= 0xffbe)
639      || (c >= 0xffc2 && c <= 0xffc7)
640      || (c >= 0xffca && c <= 0xffcf)
641      || (c >= 0xffd2 && c <= 0xffd7)
642      || (c >= 0xffda && c <= 0xffdc)
643      || (c >= 0x4e00 && c <= 0x9fa5))
644    return 1;
645
646  error ("universal-character-name '\\u%04x' not valid in identifier", c);
647  return 1;
648#endif
649}
650
651/* Add the UTF-8 representation of C to the token_buffer.  */
652
653static void
654utf8_extend_token (c)
655     int c;
656{
657  int shift, mask;
658
659  if      (c <= 0x0000007f)
660    {
661      extend_token (c);
662      return;
663    }
664  else if (c <= 0x000007ff)
665    shift = 6, mask = 0xc0;
666  else if (c <= 0x0000ffff)
667    shift = 12, mask = 0xe0;
668  else if (c <= 0x001fffff)
669    shift = 18, mask = 0xf0;
670  else if (c <= 0x03ffffff)
671    shift = 24, mask = 0xf8;
672  else
673    shift = 30, mask = 0xfc;
674
675  extend_token (mask | (c >> shift));
676  do
677    {
678      shift -= 6;
679      extend_token ((unsigned char) (0x80 | (c >> shift)));
680    }
681  while (shift);
682}
683#endif
684
685#if 0
686struct try_type
687{
688  tree *const node_var;
689  const char unsigned_flag;
690  const char long_flag;
691  const char long_long_flag;
692};
693
694struct try_type type_sequence[] =
695{
696  { &integer_type_node, 0, 0, 0},
697  { &unsigned_type_node, 1, 0, 0},
698  { &long_integer_type_node, 0, 1, 0},
699  { &long_unsigned_type_node, 1, 1, 0},
700  { &long_long_integer_type_node, 0, 1, 1},
701  { &long_long_unsigned_type_node, 1, 1, 1}
702};
703#endif /* 0 */
704
705struct pf_args
706{
707  /* Input */
708  const char *str;
709  int fflag;
710  int lflag;
711  int base;
712  /* Output */
713  int conversion_errno;
714  REAL_VALUE_TYPE value;
715  tree type;
716};
717
718static void
719parse_float (data)
720  PTR data;
721{
722  struct pf_args * args = (struct pf_args *) data;
723  const char *typename;
724
725  args->conversion_errno = 0;
726  args->type = double_type_node;
727  typename = "double";
728
729  /* The second argument, machine_mode, of REAL_VALUE_ATOF
730     tells the desired precision of the binary result
731     of decimal-to-binary conversion.  */
732
733  if (args->fflag)
734    {
735      if (args->lflag)
736	error ("both 'f' and 'l' suffixes on floating constant");
737
738      args->type = float_type_node;
739      typename = "float";
740    }
741  else if (args->lflag)
742    {
743      args->type = long_double_type_node;
744      typename = "long double";
745    }
746  else if (flag_single_precision_constant)
747    {
748      args->type = float_type_node;
749      typename = "float";
750    }
751
752  errno = 0;
753  if (args->base == 16)
754    args->value = REAL_VALUE_HTOF (args->str, TYPE_MODE (args->type));
755  else
756    args->value = REAL_VALUE_ATOF (args->str, TYPE_MODE (args->type));
757
758  args->conversion_errno = errno;
759  /* A diagnostic is required here by some ISO C testsuites.
760     This is not pedwarn, because some people don't want
761     an error for this.  */
762  if (REAL_VALUE_ISINF (args->value) && pedantic)
763    warning ("floating point number exceeds range of '%s'", typename);
764}
765
766int
767c_lex (value)
768     tree *value;
769{
770  const cpp_token *tok;
771
772  retry:
773  timevar_push (TV_CPP);
774  do
775    tok = cpp_get_token (parse_in);
776  while (tok->type == CPP_PADDING);
777  timevar_pop (TV_CPP);
778
779  /* The C++ front end does horrible things with the current line
780     number.  To ensure an accurate line number, we must reset it
781     every time we return a token.  */
782  lineno = src_lineno;
783
784  *value = NULL_TREE;
785  switch (tok->type)
786    {
787    case CPP_OPEN_BRACE:  indent_level++;  break;
788    case CPP_CLOSE_BRACE: indent_level--;  break;
789
790    /* Issue this error here, where we can get at tok->val.c.  */
791    case CPP_OTHER:
792      if (ISGRAPH (tok->val.c))
793	error ("stray '%c' in program", tok->val.c);
794      else
795	error ("stray '\\%o' in program", tok->val.c);
796      goto retry;
797
798    case CPP_NAME:
799      *value = HT_IDENT_TO_GCC_IDENT (HT_NODE (tok->val.node));
800      break;
801
802    case CPP_NUMBER:
803      *value = lex_number ((const char *)tok->val.str.text, tok->val.str.len);
804      break;
805
806    case CPP_CHAR:
807    case CPP_WCHAR:
808      *value = lex_charconst (tok);
809      break;
810
811    case CPP_STRING:
812    case CPP_WSTRING:
813      *value = lex_string (tok->val.str.text, tok->val.str.len,
814			   tok->type == CPP_WSTRING);
815      break;
816
817      /* These tokens should not be visible outside cpplib.  */
818    case CPP_HEADER_NAME:
819    case CPP_COMMENT:
820    case CPP_MACRO_ARG:
821      abort ();
822
823    default: break;
824    }
825
826  return tok->type;
827}
828
829#define ERROR(msgid) do { error(msgid); goto syntax_error; } while(0)
830
831static tree
832lex_number (str, len)
833     const char *str;
834     unsigned int len;
835{
836  int base = 10;
837  int count = 0;
838  int largest_digit = 0;
839  int numdigits = 0;
840  int overflow = 0;
841  int c;
842  tree value;
843  const char *p;
844  enum anon1 { NOT_FLOAT = 0, AFTER_POINT, AFTER_EXPON } floatflag = NOT_FLOAT;
845
846  /* We actually store only HOST_BITS_PER_CHAR bits in each part.
847     The code below which fills the parts array assumes that a host
848     int is at least twice as wide as a host char, and that
849     HOST_BITS_PER_WIDE_INT is an even multiple of HOST_BITS_PER_CHAR.
850     Two HOST_WIDE_INTs is the largest int literal we can store.
851     In order to detect overflow below, the number of parts (TOTAL_PARTS)
852     must be exactly the number of parts needed to hold the bits
853     of two HOST_WIDE_INTs.  */
854#define TOTAL_PARTS ((HOST_BITS_PER_WIDE_INT / HOST_BITS_PER_CHAR) * 2)
855  unsigned int parts[TOTAL_PARTS];
856
857  /* Optimize for most frequent case.  */
858  if (len == 1)
859    {
860      if (*str == '0')
861	return integer_zero_node;
862      else if (*str == '1')
863	return integer_one_node;
864      else
865	return build_int_2 (*str - '0', 0);
866    }
867
868  for (count = 0; count < TOTAL_PARTS; count++)
869    parts[count] = 0;
870
871  /* len is known to be >1 at this point.  */
872  p = str;
873
874  if (len > 2 && str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
875    {
876      base = 16;
877      p = str + 2;
878    }
879  /* The ISDIGIT check is so we are not confused by a suffix on 0.  */
880  else if (str[0] == '0' && ISDIGIT (str[1]))
881    {
882      base = 8;
883      p = str + 1;
884    }
885
886  do
887    {
888      c = *p++;
889
890      if (c == '.')
891	{
892	  if (floatflag == AFTER_POINT)
893	    ERROR ("too many decimal points in floating constant");
894	  else if (floatflag == AFTER_EXPON)
895	    ERROR ("decimal point in exponent - impossible!");
896	  else
897	    floatflag = AFTER_POINT;
898
899	  if (base == 8)
900	    base = 10;
901	}
902      else if (c == '_')
903	/* Possible future extension: silently ignore _ in numbers,
904	   permitting cosmetic grouping - e.g. 0x8000_0000 == 0x80000000
905	   but somewhat easier to read.  Ada has this?  */
906	ERROR ("underscore in number");
907      else
908	{
909	  int n;
910	  /* It is not a decimal point.
911	     It should be a digit (perhaps a hex digit).  */
912
913	  if (ISDIGIT (c)
914	      || (base == 16 && ISXDIGIT (c)))
915	    {
916	      n = hex_value (c);
917	    }
918	  else if (base <= 10 && (c == 'e' || c == 'E'))
919	    {
920	      base = 10;
921	      floatflag = AFTER_EXPON;
922	      break;
923	    }
924	  else if (base == 16 && (c == 'p' || c == 'P'))
925	    {
926	      floatflag = AFTER_EXPON;
927	      break;   /* start of exponent */
928	    }
929	  else
930	    {
931	      p--;
932	      break;  /* start of suffix */
933	    }
934
935	  if (n >= largest_digit)
936	    largest_digit = n;
937	  numdigits++;
938
939	  for (count = 0; count < TOTAL_PARTS; count++)
940	    {
941	      parts[count] *= base;
942	      if (count)
943		{
944		  parts[count]
945		    += (parts[count-1] >> HOST_BITS_PER_CHAR);
946		  parts[count-1]
947		    &= (1 << HOST_BITS_PER_CHAR) - 1;
948		}
949	      else
950		parts[0] += n;
951	    }
952
953	  /* If the highest-order part overflows (gets larger than
954	     a host char will hold) then the whole number has
955	     overflowed.  Record this and truncate the highest-order
956	     part.  */
957	  if (parts[TOTAL_PARTS - 1] >> HOST_BITS_PER_CHAR)
958	    {
959	      overflow = 1;
960	      parts[TOTAL_PARTS - 1] &= (1 << HOST_BITS_PER_CHAR) - 1;
961	    }
962	}
963    }
964  while (p < str + len);
965
966  /* This can happen on input like `int i = 0x;' */
967  if (numdigits == 0)
968    ERROR ("numeric constant with no digits");
969
970  if (largest_digit >= base)
971    ERROR ("numeric constant contains digits beyond the radix");
972
973  if (floatflag != NOT_FLOAT)
974    {
975      tree type;
976      int imag, fflag, lflag, conversion_errno;
977      REAL_VALUE_TYPE real;
978      struct pf_args args;
979      char *copy;
980
981      if (base == 16 && pedantic && !flag_isoc99)
982	pedwarn ("floating constant may not be in radix 16");
983
984      if (base == 16 && floatflag != AFTER_EXPON)
985	ERROR ("hexadecimal floating constant has no exponent");
986
987      /* Read explicit exponent if any, and put it in tokenbuf.  */
988      if ((base == 10 && ((c == 'e') || (c == 'E')))
989	  || (base == 16 && (c == 'p' || c == 'P')))
990	{
991	  if (p < str + len)
992	    c = *p++;
993	  if (p < str + len && (c == '+' || c == '-'))
994	    c = *p++;
995	  /* Exponent is decimal, even if string is a hex float.  */
996	  if (! ISDIGIT (c))
997	    ERROR ("floating constant exponent has no digits");
998	  while (p < str + len && ISDIGIT (c))
999	    c = *p++;
1000	  if (! ISDIGIT (c))
1001	    p--;
1002	}
1003
1004      /* Copy the float constant now; we don't want any suffixes in the
1005	 string passed to parse_float.  */
1006      copy = alloca (p - str + 1);
1007      memcpy (copy, str, p - str);
1008      copy[p - str] = '\0';
1009
1010      /* Now parse suffixes.  */
1011      fflag = lflag = imag = 0;
1012      while (p < str + len)
1013	switch (*p++)
1014	  {
1015	  case 'f': case 'F':
1016	    if (fflag)
1017	      ERROR ("more than one 'f' suffix on floating constant");
1018	    else if (warn_traditional && !in_system_header
1019		     && ! cpp_sys_macro_p (parse_in))
1020	      warning ("traditional C rejects the 'f' suffix");
1021
1022	    fflag = 1;
1023	    break;
1024
1025	  case 'l': case 'L':
1026	    if (lflag)
1027	      ERROR ("more than one 'l' suffix on floating constant");
1028	    else if (warn_traditional && !in_system_header
1029		     && ! cpp_sys_macro_p (parse_in))
1030	      warning ("traditional C rejects the 'l' suffix");
1031
1032	    lflag = 1;
1033	    break;
1034
1035	  case 'i': case 'I':
1036	  case 'j': case 'J':
1037	    if (imag)
1038	      ERROR ("more than one 'i' or 'j' suffix on floating constant");
1039	    else if (pedantic)
1040	      pedwarn ("ISO C forbids imaginary numeric constants");
1041	    imag = 1;
1042	    break;
1043
1044	  default:
1045	    ERROR ("invalid suffix on floating constant");
1046	  }
1047
1048      /* Setup input for parse_float() */
1049      args.str = copy;
1050      args.fflag = fflag;
1051      args.lflag = lflag;
1052      args.base = base;
1053
1054      /* Convert string to a double, checking for overflow.  */
1055      if (do_float_handler (parse_float, (PTR) &args))
1056	{
1057	  /* Receive output from parse_float() */
1058	  real = args.value;
1059	}
1060      else
1061	  /* We got an exception from parse_float() */
1062	  ERROR ("floating constant out of range");
1063
1064      /* Receive output from parse_float() */
1065      conversion_errno = args.conversion_errno;
1066      type = args.type;
1067
1068#ifdef ERANGE
1069      /* ERANGE is also reported for underflow,
1070	 so test the value to distinguish overflow from that.  */
1071      if (conversion_errno == ERANGE && !flag_traditional && pedantic
1072	  && (REAL_VALUES_LESS (dconst1, real)
1073	      || REAL_VALUES_LESS (real, dconstm1)))
1074	warning ("floating point number exceeds range of 'double'");
1075#endif
1076
1077      /* Create a node with determined type and value.  */
1078      if (imag)
1079	value = build_complex (NULL_TREE, convert (type, integer_zero_node),
1080			       build_real (type, real));
1081      else
1082	value = build_real (type, real);
1083    }
1084  else
1085    {
1086      tree trad_type, ansi_type, type;
1087      HOST_WIDE_INT high, low;
1088      int spec_unsigned = 0;
1089      int spec_long = 0;
1090      int spec_long_long = 0;
1091      int spec_imag = 0;
1092      int suffix_lu = 0;
1093      int warn = 0, i;
1094
1095      trad_type = ansi_type = type = NULL_TREE;
1096      while (p < str + len)
1097	{
1098	  c = *p++;
1099	  switch (c)
1100	    {
1101	    case 'u': case 'U':
1102	      if (spec_unsigned)
1103		error ("two 'u' suffixes on integer constant");
1104	      else if (warn_traditional && !in_system_header
1105		       && ! cpp_sys_macro_p (parse_in))
1106		warning ("traditional C rejects the 'u' suffix");
1107
1108	      spec_unsigned = 1;
1109	      if (spec_long)
1110		suffix_lu = 1;
1111	      break;
1112
1113	    case 'l': case 'L':
1114	      if (spec_long)
1115		{
1116		  if (spec_long_long)
1117		    error ("three 'l' suffixes on integer constant");
1118		  else if (suffix_lu)
1119		    error ("'lul' is not a valid integer suffix");
1120		  else if (c != spec_long)
1121		    error ("'Ll' and 'lL' are not valid integer suffixes");
1122		  else if (pedantic && ! flag_isoc99
1123			   && ! in_system_header && warn_long_long)
1124		    pedwarn ("ISO C89 forbids long long integer constants");
1125		  spec_long_long = 1;
1126		}
1127	      spec_long = c;
1128	      break;
1129
1130	    case 'i': case 'I': case 'j': case 'J':
1131	      if (spec_imag)
1132		error ("more than one 'i' or 'j' suffix on integer constant");
1133	      else if (pedantic)
1134		pedwarn ("ISO C forbids imaginary numeric constants");
1135	      spec_imag = 1;
1136	      break;
1137
1138	    default:
1139	      ERROR ("invalid suffix on integer constant");
1140	    }
1141	}
1142
1143      /* If the literal overflowed, pedwarn about it now.  */
1144      if (overflow)
1145	{
1146	  warn = 1;
1147	  pedwarn ("integer constant is too large for this configuration of the compiler - truncated to %d bits", HOST_BITS_PER_WIDE_INT * 2);
1148	}
1149
1150      /* This is simplified by the fact that our constant
1151	 is always positive.  */
1152
1153      high = low = 0;
1154
1155      for (i = 0; i < HOST_BITS_PER_WIDE_INT / HOST_BITS_PER_CHAR; i++)
1156	{
1157	  high |= ((HOST_WIDE_INT) parts[i + (HOST_BITS_PER_WIDE_INT
1158					      / HOST_BITS_PER_CHAR)]
1159		   << (i * HOST_BITS_PER_CHAR));
1160	  low |= (HOST_WIDE_INT) parts[i] << (i * HOST_BITS_PER_CHAR);
1161	}
1162
1163      value = build_int_2 (low, high);
1164      TREE_TYPE (value) = long_long_unsigned_type_node;
1165
1166      /* If warn_traditional, calculate both the ISO type and the
1167	 traditional type, then see if they disagree.
1168	 Otherwise, calculate only the type for the dialect in use.  */
1169      if (warn_traditional || flag_traditional)
1170	{
1171	  /* Calculate the traditional type.  */
1172	  /* Traditionally, any constant is signed; but if unsigned is
1173	     specified explicitly, obey that.  Use the smallest size
1174	     with the right number of bits, except for one special
1175	     case with decimal constants.  */
1176	  if (! spec_long && base != 10
1177	      && int_fits_type_p (value, unsigned_type_node))
1178	    trad_type = spec_unsigned ? unsigned_type_node : integer_type_node;
1179	  /* A decimal constant must be long if it does not fit in
1180	     type int.  I think this is independent of whether the
1181	     constant is signed.  */
1182	  else if (! spec_long && base == 10
1183		   && int_fits_type_p (value, integer_type_node))
1184	    trad_type = spec_unsigned ? unsigned_type_node : integer_type_node;
1185	  else if (! spec_long_long)
1186	    trad_type = (spec_unsigned
1187			 ? long_unsigned_type_node
1188			 : long_integer_type_node);
1189	  else if (int_fits_type_p (value,
1190				    spec_unsigned
1191				    ? long_long_unsigned_type_node
1192				    : long_long_integer_type_node))
1193	    trad_type = (spec_unsigned
1194			 ? long_long_unsigned_type_node
1195			 : long_long_integer_type_node);
1196	  else
1197	    trad_type = (spec_unsigned
1198			 ? widest_unsigned_literal_type_node
1199			 : widest_integer_literal_type_node);
1200	}
1201      if (warn_traditional || ! flag_traditional)
1202	{
1203	  /* Calculate the ISO type.  */
1204	  if (! spec_long && ! spec_unsigned
1205	      && int_fits_type_p (value, integer_type_node))
1206	    ansi_type = integer_type_node;
1207	  else if (! spec_long && (base != 10 || spec_unsigned)
1208		   && int_fits_type_p (value, unsigned_type_node))
1209	    ansi_type = unsigned_type_node;
1210	  else if (! spec_unsigned && !spec_long_long
1211		   && int_fits_type_p (value, long_integer_type_node))
1212	    ansi_type = long_integer_type_node;
1213	  else if (! spec_long_long
1214		   && int_fits_type_p (value, long_unsigned_type_node))
1215	    ansi_type = long_unsigned_type_node;
1216	  else if (! spec_unsigned
1217		   && int_fits_type_p (value, long_long_integer_type_node))
1218	    ansi_type = long_long_integer_type_node;
1219	  else if (int_fits_type_p (value, long_long_unsigned_type_node))
1220	    ansi_type = long_long_unsigned_type_node;
1221	  else if (! spec_unsigned
1222		   && int_fits_type_p (value, widest_integer_literal_type_node))
1223	    ansi_type = widest_integer_literal_type_node;
1224	  else
1225	    ansi_type = widest_unsigned_literal_type_node;
1226	}
1227
1228      type = flag_traditional ? trad_type : ansi_type;
1229
1230      /* We assume that constants specified in a non-decimal
1231	 base are bit patterns, and that the programmer really
1232	 meant what they wrote.  */
1233      if (warn_traditional && !in_system_header
1234	  && base == 10 && trad_type != ansi_type)
1235	{
1236	  if (TYPE_PRECISION (trad_type) != TYPE_PRECISION (ansi_type))
1237	    warning ("width of integer constant changes with -traditional");
1238	  else if (TREE_UNSIGNED (trad_type) != TREE_UNSIGNED (ansi_type))
1239	    warning ("integer constant is unsigned in ISO C, signed with -traditional");
1240	  else
1241	    warning ("width of integer constant may change on other systems with -traditional");
1242	}
1243
1244      if (pedantic && !flag_traditional && (flag_isoc99 || !spec_long_long)
1245	  && !warn
1246	  && ((flag_isoc99
1247	       ? TYPE_PRECISION (long_long_integer_type_node)
1248	       : TYPE_PRECISION (long_integer_type_node)) < TYPE_PRECISION (type)))
1249	{
1250	  warn = 1;
1251	  pedwarn ("integer constant larger than the maximum value of %s",
1252		   (flag_isoc99
1253		    ? (TREE_UNSIGNED (type)
1254		       ? _("an unsigned long long int")
1255		       : _("a long long int"))
1256		    : _("an unsigned long int")));
1257	}
1258
1259      if (base == 10 && ! spec_unsigned && TREE_UNSIGNED (type))
1260	warning ("decimal constant is so large that it is unsigned");
1261
1262      if (spec_imag)
1263	{
1264	  if (TYPE_PRECISION (type)
1265	      <= TYPE_PRECISION (integer_type_node))
1266	    value = build_complex (NULL_TREE, integer_zero_node,
1267				   convert (integer_type_node, value));
1268	  else
1269	    ERROR ("complex integer constant is too wide for 'complex int'");
1270	}
1271      else if (flag_traditional && !int_fits_type_p (value, type))
1272	/* The traditional constant 0x80000000 is signed
1273	   but doesn't fit in the range of int.
1274	   This will change it to -0x80000000, which does fit.  */
1275	{
1276	  TREE_TYPE (value) = unsigned_type (type);
1277	  value = convert (type, value);
1278	  TREE_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (value) = 0;
1279	}
1280      else
1281	TREE_TYPE (value) = type;
1282
1283      /* If it's still an integer (not a complex), and it doesn't
1284	 fit in the type we choose for it, then pedwarn.  */
1285
1286      if (! warn
1287	  && TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
1288	  && ! int_fits_type_p (value, TREE_TYPE (value)))
1289	pedwarn ("integer constant is larger than the maximum value for its type");
1290    }
1291
1292  if (p < str + len)
1293    error ("missing white space after number '%.*s'", (int) (p - str), str);
1294
1295  return value;
1296
1297 syntax_error:
1298  return integer_zero_node;
1299}
1300
1301static tree
1302lex_string (str, len, wide)
1303     const unsigned char *str;
1304     unsigned int len;
1305     int wide;
1306{
1307  tree value;
1308  char *buf = alloca ((len + 1) * (wide ? WCHAR_BYTES : 1));
1309  char *q = buf;
1310  const unsigned char *p = str, *limit = str + len;
1311  unsigned int c;
1312  unsigned width = wide ? WCHAR_TYPE_SIZE
1313			: TYPE_PRECISION (char_type_node);
1314
1315#ifdef MULTIBYTE_CHARS
1316  /* Reset multibyte conversion state.  */
1317  (void) local_mbtowc (NULL, NULL, 0);
1318#endif
1319
1320  while (p < limit)
1321    {
1322#ifdef MULTIBYTE_CHARS
1323      wchar_t wc;
1324      int char_len;
1325
1326      char_len = local_mbtowc (&wc, (const char *) p, limit - p);
1327      if (char_len == -1)
1328	{
1329	  warning ("ignoring invalid multibyte character");
1330	  char_len = 1;
1331	  c = *p++;
1332	}
1333      else
1334	{
1335	  p += char_len;
1336	  c = wc;
1337	}
1338#else
1339      c = *p++;
1340#endif
1341
1342      if (c == '\\' && !ignore_escape_flag)
1343	{
1344	  unsigned int mask;
1345
1346	  if (width < HOST_BITS_PER_INT)
1347	    mask = ((unsigned int) 1 << width) - 1;
1348	  else
1349	    mask = ~0;
1350	  c = cpp_parse_escape (parse_in, &p, limit,
1351				mask, flag_traditional);
1352	}
1353
1354      /* Add this single character into the buffer either as a wchar_t
1355	 or as a single byte.  */
1356      if (wide)
1357	{
1358	  unsigned charwidth = TYPE_PRECISION (char_type_node);
1359	  unsigned bytemask = (1 << charwidth) - 1;
1360	  int byte;
1361
1362	  for (byte = 0; byte < WCHAR_BYTES; ++byte)
1363	    {
1364	      int n;
1365	      if (byte >= (int) sizeof (c))
1366		n = 0;
1367	      else
1368		n = (c >> (byte * charwidth)) & bytemask;
1369	      if (BYTES_BIG_ENDIAN)
1370		q[WCHAR_BYTES - byte - 1] = n;
1371	      else
1372		q[byte] = n;
1373	    }
1374	  q += WCHAR_BYTES;
1375	}
1376      else
1377	{
1378	  *q++ = c;
1379	}
1380    }
1381
1382  /* Terminate the string value, either with a single byte zero
1383     or with a wide zero.  */
1384
1385  if (wide)
1386    {
1387      memset (q, 0, WCHAR_BYTES);
1388      q += WCHAR_BYTES;
1389    }
1390  else
1391    {
1392      *q++ = '\0';
1393    }
1394
1395  value = build_string (q - buf, buf);
1396
1397  if (wide)
1398    TREE_TYPE (value) = wchar_array_type_node;
1399  else
1400    TREE_TYPE (value) = char_array_type_node;
1401  return value;
1402}
1403
1404/* Converts a (possibly wide) character constant token into a tree.  */
1405static tree
1406lex_charconst (token)
1407     const cpp_token *token;
1408{
1409  HOST_WIDE_INT result;
1410  tree type, value;
1411  unsigned int chars_seen;
1412
1413  result = cpp_interpret_charconst (parse_in, token, warn_multichar,
1414 				    flag_traditional, &chars_seen);
1415  if (token->type == CPP_WCHAR)
1416    {
1417      value = build_int_2 (result, 0);
1418      type = wchar_type_node;
1419    }
1420  else
1421    {
1422      if (result < 0)
1423 	value = build_int_2 (result, -1);
1424      else
1425 	value = build_int_2 (result, 0);
1426
1427      /* In C, a character constant has type 'int'.
1428 	 In C++ 'char', but multi-char charconsts have type 'int'.  */
1429      if (c_language == clk_cplusplus && chars_seen <= 1)
1430	type = char_type_node;
1431      else
1432	type = integer_type_node;
1433    }
1434
1435  /* cpp_interpret_charconst issues a warning if the constant
1436     overflows, but if the number fits in HOST_WIDE_INT anyway, it
1437     will return it un-truncated, which may cause problems down the
1438     line.  So set the type to widest_integer_literal_type, call
1439     convert to truncate it to the proper type, then clear
1440     TREE_OVERFLOW so we don't get a second warning.
1441
1442     FIXME: cpplib's assessment of overflow may not be accurate on a
1443     platform where the final type can change at (compiler's) runtime.  */
1444
1445  TREE_TYPE (value) = widest_integer_literal_type_node;
1446  value = convert (type, value);
1447  TREE_OVERFLOW (value) = 0;
1448
1449  return value;
1450}
1451