PR target/16201
[official-gcc.git] / gcc / c-lex.c
blobf5425ce49e901b09b9da2e06b6427f921e741948
1 /* Mainly the interface between cpplib and the C front ends.
2 Copyright (C) 1987, 1988, 1989, 1992, 1994, 1995, 1996, 1997
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
27 #include "real.h"
28 #include "rtl.h"
29 #include "tree.h"
30 #include "input.h"
31 #include "output.h"
32 #include "c-tree.h"
33 #include "c-common.h"
34 #include "flags.h"
35 #include "timevar.h"
36 #include "cpplib.h"
37 #include "c-pragma.h"
38 #include "toplev.h"
39 #include "intl.h"
40 #include "tm_p.h"
41 #include "splay-tree.h"
42 #include "debug.h"
44 /* We may keep statistics about how long which files took to compile. */
45 static int header_time, body_time;
46 static splay_tree file_info_tree;
48 #undef WCHAR_TYPE_SIZE
49 #define WCHAR_TYPE_SIZE TYPE_PRECISION (wchar_type_node)
51 /* Number of bytes in a wide character. */
52 #define WCHAR_BYTES (WCHAR_TYPE_SIZE / BITS_PER_UNIT)
54 int pending_lang_change; /* If we need to switch languages - C++ only */
55 int c_header_level; /* depth in C headers - C++ only */
57 /* If we need to translate characters received. This is tri-state:
58 0 means use only the untranslated string; 1 means use only
59 the translated string; -1 means chain the translated string
60 to the untranslated one. */
61 int c_lex_string_translate = 1;
63 /* True if strings should be passed to the caller of c_lex completely
64 unmolested (no concatenation, no translation). */
65 bool c_lex_return_raw_strings = false;
67 static tree interpret_integer (const cpp_token *, unsigned int);
68 static tree interpret_float (const cpp_token *, unsigned int);
69 static enum integer_type_kind narrowest_unsigned_type
70 (unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT, unsigned int);
71 static enum integer_type_kind narrowest_signed_type
72 (unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT, unsigned int);
73 static enum cpp_ttype lex_string (const cpp_token *, tree *, bool);
74 static tree lex_charconst (const cpp_token *);
75 static void update_header_times (const char *);
76 static int dump_one_header (splay_tree_node, void *);
77 static void cb_line_change (cpp_reader *, const cpp_token *, int);
78 static void cb_ident (cpp_reader *, unsigned int, const cpp_string *);
79 static void cb_def_pragma (cpp_reader *, unsigned int);
80 static void cb_define (cpp_reader *, unsigned int, cpp_hashnode *);
81 static void cb_undef (cpp_reader *, unsigned int, cpp_hashnode *);
83 void
84 init_c_lex (void)
86 struct cpp_callbacks *cb;
87 struct c_fileinfo *toplevel;
89 /* The get_fileinfo data structure must be initialized before
90 cpp_read_main_file is called. */
91 toplevel = get_fileinfo ("<top level>");
92 if (flag_detailed_statistics)
94 header_time = 0;
95 body_time = get_run_time ();
96 toplevel->time = body_time;
99 cb = cpp_get_callbacks (parse_in);
101 cb->line_change = cb_line_change;
102 cb->ident = cb_ident;
103 cb->def_pragma = cb_def_pragma;
104 cb->valid_pch = c_common_valid_pch;
105 cb->read_pch = c_common_read_pch;
107 /* Set the debug callbacks if we can use them. */
108 if (debug_info_level == DINFO_LEVEL_VERBOSE
109 && (write_symbols == DWARF2_DEBUG
110 || write_symbols == VMS_AND_DWARF2_DEBUG))
112 cb->define = cb_define;
113 cb->undef = cb_undef;
117 struct c_fileinfo *
118 get_fileinfo (const char *name)
120 splay_tree_node n;
121 struct c_fileinfo *fi;
123 if (!file_info_tree)
124 file_info_tree = splay_tree_new ((splay_tree_compare_fn) strcmp,
126 (splay_tree_delete_value_fn) free);
128 n = splay_tree_lookup (file_info_tree, (splay_tree_key) name);
129 if (n)
130 return (struct c_fileinfo *) n->value;
132 fi = XNEW (struct c_fileinfo);
133 fi->time = 0;
134 fi->interface_only = 0;
135 fi->interface_unknown = 1;
136 splay_tree_insert (file_info_tree, (splay_tree_key) name,
137 (splay_tree_value) fi);
138 return fi;
141 static void
142 update_header_times (const char *name)
144 /* Changing files again. This means currently collected time
145 is charged against header time, and body time starts back at 0. */
146 if (flag_detailed_statistics)
148 int this_time = get_run_time ();
149 struct c_fileinfo *file = get_fileinfo (name);
150 header_time += this_time - body_time;
151 file->time += this_time - body_time;
152 body_time = this_time;
156 static int
157 dump_one_header (splay_tree_node n, void * ARG_UNUSED (dummy))
159 print_time ((const char *) n->key,
160 ((struct c_fileinfo *) n->value)->time);
161 return 0;
164 void
165 dump_time_statistics (void)
167 struct c_fileinfo *file = get_fileinfo (input_filename);
168 int this_time = get_run_time ();
169 file->time += this_time - body_time;
171 fprintf (stderr, "\n******\n");
172 print_time ("header files (total)", header_time);
173 print_time ("main file (total)", this_time - body_time);
174 fprintf (stderr, "ratio = %g : 1\n",
175 (double) header_time / (double) (this_time - body_time));
176 fprintf (stderr, "\n******\n");
178 splay_tree_foreach (file_info_tree, dump_one_header, 0);
181 static void
182 cb_ident (cpp_reader * ARG_UNUSED (pfile),
183 unsigned int ARG_UNUSED (line),
184 const cpp_string * ARG_UNUSED (str))
186 #ifdef ASM_OUTPUT_IDENT
187 if (!flag_no_ident)
189 /* Convert escapes in the string. */
190 cpp_string cstr = { 0, 0 };
191 if (cpp_interpret_string (pfile, str, 1, &cstr, false))
193 ASM_OUTPUT_IDENT (asm_out_file, (const char *) cstr.text);
194 free ((void *) cstr.text);
197 #endif
200 /* Called at the start of every non-empty line. TOKEN is the first
201 lexed token on the line. Used for diagnostic line numbers. */
202 static void
203 cb_line_change (cpp_reader * ARG_UNUSED (pfile), const cpp_token *token,
204 int parsing_args)
206 if (token->type != CPP_EOF && !parsing_args)
207 #ifdef USE_MAPPED_LOCATION
208 input_location = token->src_loc;
209 #else
211 source_location loc = token->src_loc;
212 const struct line_map *map = linemap_lookup (&line_table, loc);
213 input_line = SOURCE_LINE (map, loc);
215 #endif
218 void
219 fe_file_change (const struct line_map *new_map)
221 if (new_map == NULL)
222 return;
224 if (new_map->reason == LC_ENTER)
226 /* Don't stack the main buffer on the input stack;
227 we already did in compile_file. */
228 if (!MAIN_FILE_P (new_map))
230 #ifdef USE_MAPPED_LOCATION
231 int included_at = LAST_SOURCE_LINE_LOCATION (new_map - 1);
233 input_location = included_at;
234 push_srcloc (new_map->start_location);
235 #else
236 int included_at = LAST_SOURCE_LINE (new_map - 1);
238 input_line = included_at;
239 push_srcloc (new_map->to_file, 1);
240 #endif
241 (*debug_hooks->start_source_file) (included_at, new_map->to_file);
242 #ifndef NO_IMPLICIT_EXTERN_C
243 if (c_header_level)
244 ++c_header_level;
245 else if (new_map->sysp == 2)
247 c_header_level = 1;
248 ++pending_lang_change;
250 #endif
253 else if (new_map->reason == LC_LEAVE)
255 #ifndef NO_IMPLICIT_EXTERN_C
256 if (c_header_level && --c_header_level == 0)
258 if (new_map->sysp == 2)
259 warning ("badly nested C headers from preprocessor");
260 --pending_lang_change;
262 #endif
263 pop_srcloc ();
265 (*debug_hooks->end_source_file) (new_map->to_line);
268 update_header_times (new_map->to_file);
269 in_system_header = new_map->sysp != 0;
270 #ifdef USE_MAPPED_LOCATION
271 input_location = new_map->start_location;
272 #else
273 input_filename = new_map->to_file;
274 input_line = new_map->to_line;
275 #endif
278 static void
279 cb_def_pragma (cpp_reader *pfile, source_location loc)
281 /* Issue a warning message if we have been asked to do so. Ignore
282 unknown pragmas in system headers unless an explicit
283 -Wunknown-pragmas has been given. */
284 if (warn_unknown_pragmas > in_system_header)
286 const unsigned char *space, *name;
287 const cpp_token *s;
288 #ifndef USE_MAPPED_LOCATION
289 location_t fe_loc;
290 const struct line_map *map = linemap_lookup (&line_table, loc);
291 fe_loc.file = map->to_file;
292 fe_loc.line = SOURCE_LINE (map, loc);
293 #else
294 location_t fe_loc = loc;
295 #endif
297 space = name = (const unsigned char *) "";
298 s = cpp_get_token (pfile);
299 if (s->type != CPP_EOF)
301 space = cpp_token_as_text (pfile, s);
302 s = cpp_get_token (pfile);
303 if (s->type == CPP_NAME)
304 name = cpp_token_as_text (pfile, s);
307 warning ("%Hignoring #pragma %s %s", &fe_loc, space, name);
311 /* #define callback for DWARF and DWARF2 debug info. */
312 static void
313 cb_define (cpp_reader *pfile, source_location loc, cpp_hashnode *node)
315 const struct line_map *map = linemap_lookup (&line_table, loc);
316 (*debug_hooks->define) (SOURCE_LINE (map, loc),
317 (const char *) cpp_macro_definition (pfile, node));
320 /* #undef callback for DWARF and DWARF2 debug info. */
321 static void
322 cb_undef (cpp_reader * ARG_UNUSED (pfile), source_location loc,
323 cpp_hashnode *node)
325 const struct line_map *map = linemap_lookup (&line_table, loc);
326 (*debug_hooks->undef) (SOURCE_LINE (map, loc),
327 (const char *) NODE_NAME (node));
330 /* Read a token and return its type. Fill *VALUE with its value, if
331 applicable. Fill *CPP_FLAGS with the token's flags, if it is
332 non-NULL. */
334 enum cpp_ttype
335 c_lex_with_flags (tree *value, unsigned char *cpp_flags)
337 static bool no_more_pch;
338 const cpp_token *tok;
339 enum cpp_ttype type;
341 timevar_push (TV_CPP);
342 retry:
343 tok = cpp_get_token (parse_in);
344 type = tok->type;
346 retry_after_at:
347 switch (type)
349 case CPP_PADDING:
350 goto retry;
352 case CPP_NAME:
353 *value = HT_IDENT_TO_GCC_IDENT (HT_NODE (tok->val.node));
354 break;
356 case CPP_NUMBER:
358 unsigned int flags = cpp_classify_number (parse_in, tok);
360 switch (flags & CPP_N_CATEGORY)
362 case CPP_N_INVALID:
363 /* cpplib has issued an error. */
364 *value = error_mark_node;
365 break;
367 case CPP_N_INTEGER:
368 *value = interpret_integer (tok, flags);
369 break;
371 case CPP_N_FLOATING:
372 *value = interpret_float (tok, flags);
373 break;
375 default:
376 gcc_unreachable ();
379 break;
381 case CPP_ATSIGN:
382 /* An @ may give the next token special significance in Objective-C. */
383 if (c_dialect_objc ())
385 location_t atloc = input_location;
387 retry_at:
388 tok = cpp_get_token (parse_in);
389 type = tok->type;
390 switch (type)
392 case CPP_PADDING:
393 goto retry_at;
395 case CPP_STRING:
396 case CPP_WSTRING:
397 type = lex_string (tok, value, true);
398 break;
400 case CPP_NAME:
401 *value = HT_IDENT_TO_GCC_IDENT (HT_NODE (tok->val.node));
402 if (objc_is_reserved_word (*value))
404 type = CPP_AT_NAME;
405 break;
407 /* FALLTHROUGH */
409 default:
410 /* ... or not. */
411 error ("%Hstray %<@%> in program", &atloc);
412 goto retry_after_at;
414 break;
417 /* FALLTHROUGH */
418 case CPP_HASH:
419 case CPP_PASTE:
421 unsigned char name[4];
423 *cpp_spell_token (parse_in, tok, name) = 0;
425 error ("stray %qs in program", name);
428 goto retry;
430 case CPP_OTHER:
432 cppchar_t c = tok->val.str.text[0];
434 if (c == '"' || c == '\'')
435 error ("missing terminating %c character", (int) c);
436 else if (ISGRAPH (c))
437 error ("stray %qc in program", (int) c);
438 else
439 error ("stray %<\\%o%> in program", (int) c);
441 goto retry;
443 case CPP_CHAR:
444 case CPP_WCHAR:
445 *value = lex_charconst (tok);
446 break;
448 case CPP_STRING:
449 case CPP_WSTRING:
450 if (!c_lex_return_raw_strings)
452 type = lex_string (tok, value, false);
453 break;
456 /* FALLTHROUGH */
458 case CPP_PRAGMA:
459 *value = build_string (tok->val.str.len, (char *) tok->val.str.text);
460 break;
462 /* These tokens should not be visible outside cpplib. */
463 case CPP_HEADER_NAME:
464 case CPP_COMMENT:
465 case CPP_MACRO_ARG:
466 gcc_unreachable ();
468 default:
469 *value = NULL_TREE;
470 break;
473 if (cpp_flags)
474 *cpp_flags = tok->flags;
476 if (!no_more_pch)
478 no_more_pch = true;
479 c_common_no_more_pch ();
482 timevar_pop (TV_CPP);
484 return type;
487 enum cpp_ttype
488 c_lex (tree *value)
490 return c_lex_with_flags (value, NULL);
493 /* Returns the narrowest C-visible unsigned type, starting with the
494 minimum specified by FLAGS, that can fit HIGH:LOW, or itk_none if
495 there isn't one. */
497 static enum integer_type_kind
498 narrowest_unsigned_type (unsigned HOST_WIDE_INT low,
499 unsigned HOST_WIDE_INT high,
500 unsigned int flags)
502 enum integer_type_kind itk;
504 if ((flags & CPP_N_WIDTH) == CPP_N_SMALL)
505 itk = itk_unsigned_int;
506 else if ((flags & CPP_N_WIDTH) == CPP_N_MEDIUM)
507 itk = itk_unsigned_long;
508 else
509 itk = itk_unsigned_long_long;
511 for (; itk < itk_none; itk += 2 /* skip unsigned types */)
513 tree upper = TYPE_MAX_VALUE (integer_types[itk]);
515 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (upper) > high
516 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (upper) == high
517 && TREE_INT_CST_LOW (upper) >= low))
518 return itk;
521 return itk_none;
524 /* Ditto, but narrowest signed type. */
525 static enum integer_type_kind
526 narrowest_signed_type (unsigned HOST_WIDE_INT low,
527 unsigned HOST_WIDE_INT high, unsigned int flags)
529 enum integer_type_kind itk;
531 if ((flags & CPP_N_WIDTH) == CPP_N_SMALL)
532 itk = itk_int;
533 else if ((flags & CPP_N_WIDTH) == CPP_N_MEDIUM)
534 itk = itk_long;
535 else
536 itk = itk_long_long;
539 for (; itk < itk_none; itk += 2 /* skip signed types */)
541 tree upper = TYPE_MAX_VALUE (integer_types[itk]);
543 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (upper) > high
544 || ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (upper) == high
545 && TREE_INT_CST_LOW (upper) >= low))
546 return itk;
549 return itk_none;
552 /* Interpret TOKEN, an integer with FLAGS as classified by cpplib. */
553 static tree
554 interpret_integer (const cpp_token *token, unsigned int flags)
556 tree value, type;
557 enum integer_type_kind itk;
558 cpp_num integer;
559 cpp_options *options = cpp_get_options (parse_in);
561 integer = cpp_interpret_integer (parse_in, token, flags);
562 integer = cpp_num_sign_extend (integer, options->precision);
564 /* The type of a constant with a U suffix is straightforward. */
565 if (flags & CPP_N_UNSIGNED)
566 itk = narrowest_unsigned_type (integer.low, integer.high, flags);
567 else
569 /* The type of a potentially-signed integer constant varies
570 depending on the base it's in, the standard in use, and the
571 length suffixes. */
572 enum integer_type_kind itk_u
573 = narrowest_unsigned_type (integer.low, integer.high, flags);
574 enum integer_type_kind itk_s
575 = narrowest_signed_type (integer.low, integer.high, flags);
577 /* In both C89 and C99, octal and hex constants may be signed or
578 unsigned, whichever fits tighter. We do not warn about this
579 choice differing from the traditional choice, as the constant
580 is probably a bit pattern and either way will work. */
581 if ((flags & CPP_N_RADIX) != CPP_N_DECIMAL)
582 itk = MIN (itk_u, itk_s);
583 else
585 /* In C99, decimal constants are always signed.
586 In C89, decimal constants that don't fit in long have
587 undefined behavior; we try to make them unsigned long.
588 In GCC's extended C89, that last is true of decimal
589 constants that don't fit in long long, too. */
591 itk = itk_s;
592 if (itk_s > itk_u && itk_s > itk_long)
594 if (!flag_isoc99)
596 if (itk_u < itk_unsigned_long)
597 itk_u = itk_unsigned_long;
598 itk = itk_u;
599 warning ("this decimal constant is unsigned only in ISO C90");
601 else if (warn_traditional)
602 warning ("this decimal constant would be unsigned in ISO C90");
607 if (itk == itk_none)
608 /* cpplib has already issued a warning for overflow. */
609 type = ((flags & CPP_N_UNSIGNED)
610 ? widest_unsigned_literal_type_node
611 : widest_integer_literal_type_node);
612 else
613 type = integer_types[itk];
615 if (itk > itk_unsigned_long
616 && (flags & CPP_N_WIDTH) != CPP_N_LARGE
617 && !in_system_header && !flag_isoc99)
618 pedwarn ("integer constant is too large for %qs type",
619 (flags & CPP_N_UNSIGNED) ? "unsigned long" : "long");
621 value = build_int_cst_wide (type, integer.low, integer.high);
623 /* Convert imaginary to a complex type. */
624 if (flags & CPP_N_IMAGINARY)
625 value = build_complex (NULL_TREE, build_int_cst (type, 0), value);
627 return value;
630 /* Interpret TOKEN, a floating point number with FLAGS as classified
631 by cpplib. */
632 static tree
633 interpret_float (const cpp_token *token, unsigned int flags)
635 tree type;
636 tree value;
637 REAL_VALUE_TYPE real;
638 char *copy;
639 size_t copylen;
640 const char *type_name;
642 /* FIXME: make %T work in error/warning, then we don't need type_name. */
643 if ((flags & CPP_N_WIDTH) == CPP_N_LARGE)
645 type = long_double_type_node;
646 type_name = "long double";
648 else if ((flags & CPP_N_WIDTH) == CPP_N_SMALL
649 || flag_single_precision_constant)
651 type = float_type_node;
652 type_name = "float";
654 else
656 type = double_type_node;
657 type_name = "double";
660 /* Copy the constant to a nul-terminated buffer. If the constant
661 has any suffixes, cut them off; REAL_VALUE_ATOF/ REAL_VALUE_HTOF
662 can't handle them. */
663 copylen = token->val.str.len;
664 if ((flags & CPP_N_WIDTH) != CPP_N_MEDIUM)
665 /* Must be an F or L suffix. */
666 copylen--;
667 if (flags & CPP_N_IMAGINARY)
668 /* I or J suffix. */
669 copylen--;
671 copy = (char *) alloca (copylen + 1);
672 memcpy (copy, token->val.str.text, copylen);
673 copy[copylen] = '\0';
675 real_from_string (&real, copy);
676 real_convert (&real, TYPE_MODE (type), &real);
678 /* Both C and C++ require a diagnostic for a floating constant
679 outside the range of representable values of its type. Since we
680 have __builtin_inf* to produce an infinity, it might now be
681 appropriate for this to be a mandatory pedwarn rather than
682 conditioned on -pedantic. */
683 if (REAL_VALUE_ISINF (real) && pedantic)
684 pedwarn ("floating constant exceeds range of %<%s%>", type_name);
686 /* Create a node with determined type and value. */
687 value = build_real (type, real);
688 if (flags & CPP_N_IMAGINARY)
689 value = build_complex (NULL_TREE, convert (type, integer_zero_node), value);
691 return value;
694 /* Convert a series of STRING and/or WSTRING tokens into a tree,
695 performing string constant concatenation. TOK is the first of
696 these. VALP is the location to write the string into. OBJC_STRING
697 indicates whether an '@' token preceded the incoming token.
698 Returns the CPP token type of the result (CPP_STRING, CPP_WSTRING,
699 or CPP_OBJC_STRING).
701 This is unfortunately more work than it should be. If any of the
702 strings in the series has an L prefix, the result is a wide string
703 (6.4.5p4). Whether or not the result is a wide string affects the
704 meaning of octal and hexadecimal escapes (6.4.4.4p6,9). But escape
705 sequences do not continue across the boundary between two strings in
706 a series (6.4.5p7), so we must not lose the boundaries. Therefore
707 cpp_interpret_string takes a vector of cpp_string structures, which
708 we must arrange to provide. */
710 static enum cpp_ttype
711 lex_string (const cpp_token *tok, tree *valp, bool objc_string)
713 tree value;
714 bool wide = false;
715 size_t concats = 0;
716 struct obstack str_ob;
717 cpp_string istr;
719 /* Try to avoid the overhead of creating and destroying an obstack
720 for the common case of just one string. */
721 cpp_string str = tok->val.str;
722 cpp_string *strs = &str;
724 if (tok->type == CPP_WSTRING)
725 wide = true;
727 retry:
728 tok = cpp_get_token (parse_in);
729 switch (tok->type)
731 case CPP_PADDING:
732 goto retry;
733 case CPP_ATSIGN:
734 if (c_dialect_objc ())
736 objc_string = true;
737 goto retry;
739 /* FALLTHROUGH */
741 default:
742 break;
744 case CPP_WSTRING:
745 wide = true;
746 /* FALLTHROUGH */
748 case CPP_STRING:
749 if (!concats)
751 gcc_obstack_init (&str_ob);
752 obstack_grow (&str_ob, &str, sizeof (cpp_string));
755 concats++;
756 obstack_grow (&str_ob, &tok->val.str, sizeof (cpp_string));
757 goto retry;
760 /* We have read one more token than we want. */
761 _cpp_backup_tokens (parse_in, 1);
762 if (concats)
763 strs = (cpp_string *) obstack_finish (&str_ob);
765 if (concats && !objc_string && warn_traditional && !in_system_header)
766 warning ("traditional C rejects string constant concatenation");
768 if ((c_lex_string_translate
769 ? cpp_interpret_string : cpp_interpret_string_notranslate)
770 (parse_in, strs, concats + 1, &istr, wide))
772 value = build_string (istr.len, (char *) istr.text);
773 free ((void *) istr.text);
775 if (c_lex_string_translate == -1)
777 int xlated = cpp_interpret_string_notranslate (parse_in, strs,
778 concats + 1,
779 &istr, wide);
780 /* Assume that, if we managed to translate the string above,
781 then the untranslated parsing will always succeed. */
782 gcc_assert (xlated);
784 if (TREE_STRING_LENGTH (value) != (int) istr.len
785 || 0 != strncmp (TREE_STRING_POINTER (value), (char *) istr.text,
786 istr.len))
788 /* Arrange for us to return the untranslated string in
789 *valp, but to set up the C type of the translated
790 one. */
791 *valp = build_string (istr.len, (char *) istr.text);
792 valp = &TREE_CHAIN (*valp);
794 free ((void *) istr.text);
797 else
799 /* Callers cannot generally handle error_mark_node in this context,
800 so return the empty string instead. cpp_interpret_string has
801 issued an error. */
802 if (wide)
803 value = build_string (TYPE_PRECISION (wchar_type_node)
804 / TYPE_PRECISION (char_type_node),
805 "\0\0\0"); /* widest supported wchar_t
806 is 32 bits */
807 else
808 value = build_string (1, "");
811 TREE_TYPE (value) = wide ? wchar_array_type_node : char_array_type_node;
812 *valp = fix_string_type (value);
814 if (concats)
815 obstack_free (&str_ob, 0);
817 return objc_string ? CPP_OBJC_STRING : wide ? CPP_WSTRING : CPP_STRING;
820 /* Converts a (possibly wide) character constant token into a tree. */
821 static tree
822 lex_charconst (const cpp_token *token)
824 cppchar_t result;
825 tree type, value;
826 unsigned int chars_seen;
827 int unsignedp;
829 result = cpp_interpret_charconst (parse_in, token,
830 &chars_seen, &unsignedp);
832 if (token->type == CPP_WCHAR)
833 type = wchar_type_node;
834 /* In C, a character constant has type 'int'.
835 In C++ 'char', but multi-char charconsts have type 'int'. */
836 else if (!c_dialect_cxx () || chars_seen > 1)
837 type = integer_type_node;
838 else
839 type = char_type_node;
841 /* Cast to cppchar_signed_t to get correct sign-extension of RESULT
842 before possibly widening to HOST_WIDE_INT for build_int_cst. */
843 if (unsignedp || (cppchar_signed_t) result >= 0)
844 value = build_int_cst_wide (type, result, 0);
845 else
846 value = build_int_cst_wide (type, (cppchar_signed_t) result, -1);
848 return value;