d4691e641b
non-i386, non-unix, and generatable files have been trimmed, but can easily be added in later if needed. gcc-2.7.2.1 will follow shortly, it's a very small delta to this and it's handy to have both available for reference for such little cost. The freebsd-specific changes will then be committed, and once the dust has settled, the bmakefiles will be committed to use this code.
998 lines
24 KiB
C
998 lines
24 KiB
C
/* Parse C expressions for CCCP.
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Copyright (C) 1987, 1992, 1994, 1995 Free Software Foundation.
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This program is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation; either version 2, or (at your option) any
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later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA.
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In other words, you are welcome to use, share and improve this program.
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You are forbidden to forbid anyone else to use, share and improve
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what you give them. Help stamp out software-hoarding!
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Written by Per Bothner 1994. */
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/* Parse a C expression from text in a string */
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#include "config.h"
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#include "cpplib.h"
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extern char *xmalloc PARAMS ((unsigned));
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extern char *xrealloc PARAMS ((char *, unsigned));
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#ifdef MULTIBYTE_CHARS
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#include <stdlib.h>
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#include <locale.h>
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#endif
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#include <stdio.h>
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/* This is used for communicating lists of keywords with cccp.c. */
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struct arglist {
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struct arglist *next;
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U_CHAR *name;
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int length;
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int argno;
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};
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/* Define a generic NULL if one hasn't already been defined. */
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#ifndef NULL
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#define NULL 0
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#endif
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#ifndef GENERIC_PTR
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#if defined (USE_PROTOTYPES) ? USE_PROTOTYPES : defined (__STDC__)
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#define GENERIC_PTR void *
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#else
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#define GENERIC_PTR char *
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#endif
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#endif
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#ifndef NULL_PTR
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#define NULL_PTR ((GENERIC_PTR)0)
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#endif
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extern char *xmalloc ();
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#ifndef CHAR_TYPE_SIZE
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#define CHAR_TYPE_SIZE BITS_PER_UNIT
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#endif
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#ifndef INT_TYPE_SIZE
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#define INT_TYPE_SIZE BITS_PER_WORD
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#endif
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#ifndef LONG_TYPE_SIZE
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#define LONG_TYPE_SIZE BITS_PER_WORD
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#endif
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#ifndef WCHAR_TYPE_SIZE
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#define WCHAR_TYPE_SIZE INT_TYPE_SIZE
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#endif
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#ifndef MAX_CHAR_TYPE_SIZE
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#define MAX_CHAR_TYPE_SIZE CHAR_TYPE_SIZE
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#endif
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#ifndef MAX_INT_TYPE_SIZE
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#define MAX_INT_TYPE_SIZE INT_TYPE_SIZE
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#endif
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#ifndef MAX_LONG_TYPE_SIZE
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#define MAX_LONG_TYPE_SIZE LONG_TYPE_SIZE
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#endif
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#ifndef MAX_WCHAR_TYPE_SIZE
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#define MAX_WCHAR_TYPE_SIZE WCHAR_TYPE_SIZE
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#endif
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/* Yield nonzero if adding two numbers with A's and B's signs can yield a
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number with SUM's sign, where A, B, and SUM are all C integers. */
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#define possible_sum_sign(a, b, sum) ((((a) ^ (b)) | ~ ((a) ^ (sum))) < 0)
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static void integer_overflow ();
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static long left_shift ();
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static long right_shift ();
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#define ERROR 299
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#define OROR 300
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#define ANDAND 301
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#define EQUAL 302
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#define NOTEQUAL 303
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#define LEQ 304
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#define GEQ 305
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#define LSH 306
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#define RSH 307
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#define NAME 308
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#define INT 309
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#define CHAR 310
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#define LEFT_OPERAND_REQUIRED 1
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#define RIGHT_OPERAND_REQUIRED 2
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#define HAVE_VALUE 4
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/*#define UNSIGNEDP 8*/
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#ifndef HOST_BITS_PER_WIDE_INT
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#if HOST_BITS_PER_LONG > HOST_BITS_PER_INT
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#define HOST_BITS_PER_WIDE_INT HOST_BITS_PER_LONG
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#define HOST_WIDE_INT long
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#else
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#define HOST_BITS_PER_WIDE_INT HOST_BITS_PER_INT
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#define HOST_WIDE_INT int
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#endif
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#endif
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struct operation {
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short op;
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char rprio; /* Priority of op (relative to it right operand). */
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char flags;
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char unsignedp; /* true if value should be treated as unsigned */
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HOST_WIDE_INT value; /* The value logically "right" of op. */
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};
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/* Take care of parsing a number (anything that starts with a digit).
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LEN is the number of characters in it. */
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/* maybe needs to actually deal with floating point numbers */
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struct operation
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parse_number (pfile, start, olen)
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cpp_reader *pfile;
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char *start;
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int olen;
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{
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struct operation op;
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register char *p = start;
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register int c;
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register unsigned long n = 0, nd, ULONG_MAX_over_base;
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register int base = 10;
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register int len = olen;
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register int overflow = 0;
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register int digit, largest_digit = 0;
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int spec_long = 0;
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op.unsignedp = 0;
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for (c = 0; c < len; c++)
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if (p[c] == '.') {
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/* It's a float since it contains a point. */
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cpp_error (pfile,
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"floating point numbers not allowed in #if expressions");
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op.op = ERROR;
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return op;
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}
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if (len >= 3 && (!strncmp (p, "0x", 2) || !strncmp (p, "0X", 2))) {
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p += 2;
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base = 16;
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len -= 2;
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}
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else if (*p == '0')
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base = 8;
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/* Some buggy compilers (e.g. MPW C) seem to need both casts. */
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ULONG_MAX_over_base = ((unsigned long) -1) / ((unsigned long) base);
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for (; len > 0; len--) {
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c = *p++;
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if (c >= '0' && c <= '9')
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digit = c - '0';
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else if (base == 16 && c >= 'a' && c <= 'f')
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digit = c - 'a' + 10;
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else if (base == 16 && c >= 'A' && c <= 'F')
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digit = c - 'A' + 10;
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else {
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/* `l' means long, and `u' means unsigned. */
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while (1) {
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if (c == 'l' || c == 'L')
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{
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if (spec_long)
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cpp_error (pfile, "two `l's in integer constant");
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spec_long = 1;
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}
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else if (c == 'u' || c == 'U')
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{
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if (op.unsignedp)
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cpp_error (pfile, "two `u's in integer constant");
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op.unsignedp = 1;
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}
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else
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break;
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if (--len == 0)
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break;
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c = *p++;
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}
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/* Don't look for any more digits after the suffixes. */
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break;
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}
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if (largest_digit < digit)
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largest_digit = digit;
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nd = n * base + digit;
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overflow |= ULONG_MAX_over_base < n | nd < n;
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n = nd;
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}
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if (len != 0)
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{
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cpp_error (pfile, "Invalid number in #if expression");
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op.op = ERROR;
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return op;
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}
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if (base <= largest_digit)
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cpp_warning (pfile, "integer constant contains digits beyond the radix");
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if (overflow)
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cpp_warning (pfile, "integer constant out of range");
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/* If too big to be signed, consider it unsigned. */
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if ((long) n < 0 && ! op.unsignedp)
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{
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if (base == 10)
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cpp_warning (pfile, "integer constant is so large that it is unsigned");
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op.unsignedp = 1;
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}
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op.value = n;
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op.op = INT;
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return op;
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}
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struct token {
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char *operator;
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int token;
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};
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static struct token tokentab2[] = {
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{"&&", ANDAND},
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{"||", OROR},
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{"<<", LSH},
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{">>", RSH},
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{"==", EQUAL},
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{"!=", NOTEQUAL},
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{"<=", LEQ},
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{">=", GEQ},
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{"++", ERROR},
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{"--", ERROR},
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{NULL, ERROR}
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};
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/* Read one token. */
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struct operation
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cpp_lex (pfile)
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cpp_reader *pfile;
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{
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register int c;
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register int namelen;
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register struct token *toktab;
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enum cpp_token token;
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struct operation op;
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U_CHAR *tok_start, *tok_end;
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int old_written;
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retry:
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old_written = CPP_WRITTEN (pfile);
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cpp_skip_hspace (pfile);
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c = CPP_BUF_PEEK (CPP_BUFFER (pfile));
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if (c == '#')
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return parse_number (pfile,
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cpp_read_check_assertion (pfile) ? "1" : "0", 1);
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if (c == '\n')
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{
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op.op = 0;
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return op;
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}
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token = cpp_get_token (pfile);
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tok_start = pfile->token_buffer + old_written;
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tok_end = CPP_PWRITTEN (pfile);
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pfile->limit = tok_start;
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switch (token)
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{
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case CPP_EOF: /* Should not happen ... */
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op.op = 0;
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return op;
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case CPP_VSPACE:
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case CPP_POP:
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if (CPP_BUFFER (pfile)->fname != NULL)
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{
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op.op = 0;
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return op;
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}
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goto retry;
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case CPP_HSPACE: case CPP_COMMENT:
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goto retry;
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case CPP_NUMBER:
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return parse_number (pfile, tok_start, tok_end - tok_start);
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case CPP_STRING:
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cpp_error (pfile, "string constants not allowed in #if expressions");
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op.op = ERROR;
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return op;
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case CPP_CHAR:
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/* This code for reading a character constant
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handles multicharacter constants and wide characters.
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It is mostly copied from c-lex.c. */
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{
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register int result = 0;
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register num_chars = 0;
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unsigned width = MAX_CHAR_TYPE_SIZE;
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int wide_flag = 0;
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int max_chars;
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U_CHAR *ptr = tok_start;
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#ifdef MULTIBYTE_CHARS
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char token_buffer[MAX_LONG_TYPE_SIZE/MAX_CHAR_TYPE_SIZE + MB_CUR_MAX];
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#else
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char token_buffer[MAX_LONG_TYPE_SIZE/MAX_CHAR_TYPE_SIZE + 1];
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#endif
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if (*ptr == 'L')
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{
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ptr++;
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wide_flag = 1;
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width = MAX_WCHAR_TYPE_SIZE;
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#ifdef MULTIBYTE_CHARS
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max_chars = MB_CUR_MAX;
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#else
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max_chars = 1;
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#endif
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}
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else
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max_chars = MAX_LONG_TYPE_SIZE / width;
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++ptr;
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while (ptr < tok_end && ((c = *ptr++) != '\''))
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{
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if (c == '\\')
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{
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c = cpp_parse_escape (pfile, &ptr);
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if (width < HOST_BITS_PER_INT
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&& (unsigned) c >= (1 << width))
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cpp_pedwarn (pfile,
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"escape sequence out of range for character");
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}
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num_chars++;
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/* Merge character into result; ignore excess chars. */
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if (num_chars < max_chars + 1)
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{
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if (width < HOST_BITS_PER_INT)
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result = (result << width) | (c & ((1 << width) - 1));
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else
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result = c;
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token_buffer[num_chars - 1] = c;
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}
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}
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token_buffer[num_chars] = 0;
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if (c != '\'')
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cpp_error (pfile, "malformatted character constant");
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else if (num_chars == 0)
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cpp_error (pfile, "empty character constant");
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else if (num_chars > max_chars)
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{
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num_chars = max_chars;
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cpp_error (pfile, "character constant too long");
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}
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else if (num_chars != 1 && ! CPP_TRADITIONAL (pfile))
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cpp_warning (pfile, "multi-character character constant");
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/* If char type is signed, sign-extend the constant. */
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if (! wide_flag)
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{
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int num_bits = num_chars * width;
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if (cpp_lookup (pfile, "__CHAR_UNSIGNED__",
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sizeof ("__CHAR_UNSIGNED__")-1, -1)
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|| ((result >> (num_bits - 1)) & 1) == 0)
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op.value
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= result & ((unsigned long) ~0 >> (HOST_BITS_PER_LONG - num_bits));
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else
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op.value
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= result | ~((unsigned long) ~0 >> (HOST_BITS_PER_LONG - num_bits));
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}
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else
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{
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#ifdef MULTIBYTE_CHARS
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/* Set the initial shift state and convert the next sequence. */
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result = 0;
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/* In all locales L'\0' is zero and mbtowc will return zero,
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so don't use it. */
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if (num_chars > 1
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|| (num_chars == 1 && token_buffer[0] != '\0'))
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{
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wchar_t wc;
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(void) mbtowc (NULL_PTR, NULL_PTR, 0);
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if (mbtowc (& wc, token_buffer, num_chars) == num_chars)
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result = wc;
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else
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cpp_warning (pfile,"Ignoring invalid multibyte character");
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}
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#endif
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op.value = result;
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}
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}
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/* This is always a signed type. */
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op.unsignedp = 0;
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op.op = CHAR;
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return op;
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case CPP_NAME:
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return parse_number (pfile, "0", 0);
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case CPP_OTHER:
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/* See if it is a special token of length 2. */
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if (tok_start + 2 == tok_end)
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{
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for (toktab = tokentab2; toktab->operator != NULL; toktab++)
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if (tok_start[0] == toktab->operator[0]
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&& tok_start[1] == toktab->operator[1])
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break;
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if (toktab->token == ERROR)
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{
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char *buf = (char *) alloca (40);
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sprintf (buf, "`%s' not allowed in operand of `#if'", tok_start);
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cpp_error (pfile, buf);
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}
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op.op = toktab->token;
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return op;
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}
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/* fall through */
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default:
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op.op = *tok_start;
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return op;
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}
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}
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/* Parse a C escape sequence. STRING_PTR points to a variable
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containing a pointer to the string to parse. That pointer
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is updated past the characters we use. The value of the
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escape sequence is returned.
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A negative value means the sequence \ newline was seen,
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which is supposed to be equivalent to nothing at all.
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If \ is followed by a null character, we return a negative
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value and leave the string pointer pointing at the null character.
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If \ is followed by 000, we return 0 and leave the string pointer
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after the zeros. A value of 0 does not mean end of string. */
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int
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cpp_parse_escape (pfile, string_ptr)
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cpp_reader *pfile;
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char **string_ptr;
|
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{
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register int c = *(*string_ptr)++;
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switch (c)
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{
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case 'a':
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return TARGET_BELL;
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case 'b':
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return TARGET_BS;
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case 'e':
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case 'E':
|
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if (CPP_PEDANTIC (pfile))
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cpp_pedwarn (pfile, "non-ANSI-standard escape sequence, `\\%c'", c);
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return 033;
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case 'f':
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return TARGET_FF;
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case 'n':
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return TARGET_NEWLINE;
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case 'r':
|
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return TARGET_CR;
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case 't':
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return TARGET_TAB;
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case 'v':
|
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return TARGET_VT;
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case '\n':
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return -2;
|
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case 0:
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(*string_ptr)--;
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return 0;
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case '0':
|
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case '1':
|
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case '2':
|
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case '3':
|
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case '4':
|
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case '5':
|
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case '6':
|
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case '7':
|
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{
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register int i = c - '0';
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register int count = 0;
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while (++count < 3)
|
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{
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c = *(*string_ptr)++;
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if (c >= '0' && c <= '7')
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i = (i << 3) + c - '0';
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else
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{
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(*string_ptr)--;
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break;
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}
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}
|
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if ((i & ~((1 << MAX_CHAR_TYPE_SIZE) - 1)) != 0)
|
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{
|
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i &= (1 << MAX_CHAR_TYPE_SIZE) - 1;
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cpp_warning (pfile,
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"octal character constant does not fit in a byte");
|
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}
|
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return i;
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}
|
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case 'x':
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{
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register unsigned i = 0, overflow = 0, digits_found = 0, digit;
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for (;;)
|
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{
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c = *(*string_ptr)++;
|
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if (c >= '0' && c <= '9')
|
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digit = c - '0';
|
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else if (c >= 'a' && c <= 'f')
|
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digit = c - 'a' + 10;
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else if (c >= 'A' && c <= 'F')
|
||
digit = c - 'A' + 10;
|
||
else
|
||
{
|
||
(*string_ptr)--;
|
||
break;
|
||
}
|
||
overflow |= i ^ (i << 4 >> 4);
|
||
i = (i << 4) + digit;
|
||
digits_found = 1;
|
||
}
|
||
if (!digits_found)
|
||
cpp_error (pfile, "\\x used with no following hex digits");
|
||
if (overflow | (i & ~((1 << BITS_PER_UNIT) - 1)))
|
||
{
|
||
i &= (1 << BITS_PER_UNIT) - 1;
|
||
cpp_warning (pfile,
|
||
"hex character constant does not fit in a byte");
|
||
}
|
||
return i;
|
||
}
|
||
default:
|
||
return c;
|
||
}
|
||
}
|
||
|
||
static void
|
||
integer_overflow (pfile)
|
||
cpp_reader *pfile;
|
||
{
|
||
if (CPP_PEDANTIC (pfile))
|
||
cpp_pedwarn (pfile, "integer overflow in preprocessor expression");
|
||
}
|
||
|
||
static long
|
||
left_shift (pfile, a, unsignedp, b)
|
||
cpp_reader *pfile;
|
||
long a;
|
||
int unsignedp;
|
||
unsigned long b;
|
||
{
|
||
if (b >= HOST_BITS_PER_LONG)
|
||
{
|
||
if (! unsignedp && a != 0)
|
||
integer_overflow (pfile);
|
||
return 0;
|
||
}
|
||
else if (unsignedp)
|
||
return (unsigned long) a << b;
|
||
else
|
||
{
|
||
long l = a << b;
|
||
if (l >> b != a)
|
||
integer_overflow (pfile);
|
||
return l;
|
||
}
|
||
}
|
||
|
||
static long
|
||
right_shift (pfile, a, unsignedp, b)
|
||
cpp_reader *pfile;
|
||
long a;
|
||
int unsignedp;
|
||
unsigned long b;
|
||
{
|
||
if (b >= HOST_BITS_PER_LONG)
|
||
return unsignedp ? 0 : a >> (HOST_BITS_PER_LONG - 1);
|
||
else if (unsignedp)
|
||
return (unsigned long) a >> b;
|
||
else
|
||
return a >> b;
|
||
}
|
||
|
||
/* These priorities are all even, so we can handle associatively. */
|
||
#define PAREN_INNER_PRIO 0
|
||
#define COMMA_PRIO 4
|
||
#define COND_PRIO (COMMA_PRIO+2)
|
||
#define OROR_PRIO (COND_PRIO+2)
|
||
#define ANDAND_PRIO (OROR_PRIO+2)
|
||
#define OR_PRIO (ANDAND_PRIO+2)
|
||
#define XOR_PRIO (OR_PRIO+2)
|
||
#define AND_PRIO (XOR_PRIO+2)
|
||
#define EQUAL_PRIO (AND_PRIO+2)
|
||
#define LESS_PRIO (EQUAL_PRIO+2)
|
||
#define SHIFT_PRIO (LESS_PRIO+2)
|
||
#define PLUS_PRIO (SHIFT_PRIO+2)
|
||
#define MUL_PRIO (PLUS_PRIO+2)
|
||
#define UNARY_PRIO (MUL_PRIO+2)
|
||
#define PAREN_OUTER_PRIO (UNARY_PRIO+2)
|
||
|
||
#define COMPARE(OP) \
|
||
top->unsignedp = 0;\
|
||
top->value = (unsigned1 || unsigned2) ? (unsigned long) v1 OP v2 : (v1 OP v2)
|
||
|
||
/* Parse and evaluate a C expression, reading from PFILE.
|
||
Returns the value of the expression. */
|
||
|
||
HOST_WIDE_INT
|
||
cpp_parse_expr (pfile)
|
||
cpp_reader *pfile;
|
||
{
|
||
/* The implementation is an operator precedence parser,
|
||
i.e. a bottom-up parser, using a stack for not-yet-reduced tokens.
|
||
|
||
The stack base is 'stack', and the current stack pointer is 'top'.
|
||
There is a stack element for each operator (only),
|
||
and the most recently pushed operator is 'top->op'.
|
||
An operand (value) is stored in the 'value' field of the stack
|
||
element of the operator that precedes it.
|
||
In that case the 'flags' field has the HAVE_VALUE flag set. */
|
||
|
||
#define INIT_STACK_SIZE 20
|
||
struct operation init_stack[INIT_STACK_SIZE];
|
||
struct operation *stack = init_stack;
|
||
struct operation *limit = stack + INIT_STACK_SIZE;
|
||
register struct operation *top = stack;
|
||
int lprio, rprio;
|
||
|
||
top->rprio = 0;
|
||
top->flags = 0;
|
||
for (;;)
|
||
{
|
||
struct operation op;
|
||
char flags = 0;
|
||
|
||
/* Read a token */
|
||
op = cpp_lex (pfile);
|
||
|
||
/* See if the token is an operand, in which case go to set_value.
|
||
If the token is an operator, figure out its left and right
|
||
priorities, and then goto maybe_reduce. */
|
||
|
||
switch (op.op)
|
||
{
|
||
case NAME:
|
||
top->value = 0, top->unsignedp = 0;
|
||
goto set_value;
|
||
case INT: case CHAR:
|
||
top->value = op.value;
|
||
top->unsignedp = op.unsignedp;
|
||
goto set_value;
|
||
case 0:
|
||
lprio = 0; goto maybe_reduce;
|
||
case '+': case '-':
|
||
/* Is this correct if unary ? FIXME */
|
||
flags = RIGHT_OPERAND_REQUIRED;
|
||
lprio = PLUS_PRIO; rprio = lprio + 1; goto maybe_reduce;
|
||
case '!': case '~':
|
||
flags = RIGHT_OPERAND_REQUIRED;
|
||
rprio = UNARY_PRIO; lprio = rprio + 1; goto maybe_reduce;
|
||
case '*': case '/': case '%':
|
||
lprio = MUL_PRIO; goto binop;
|
||
case '<': case '>': case LEQ: case GEQ:
|
||
lprio = LESS_PRIO; goto binop;
|
||
case EQUAL: case NOTEQUAL:
|
||
lprio = EQUAL_PRIO; goto binop;
|
||
case LSH: case RSH:
|
||
lprio = SHIFT_PRIO; goto binop;
|
||
case '&': lprio = AND_PRIO; goto binop;
|
||
case '^': lprio = XOR_PRIO; goto binop;
|
||
case '|': lprio = OR_PRIO; goto binop;
|
||
case ANDAND: lprio = ANDAND_PRIO; goto binop;
|
||
case OROR: lprio = OROR_PRIO; goto binop;
|
||
case ',':
|
||
lprio = COMMA_PRIO; goto binop;
|
||
case '(':
|
||
lprio = PAREN_OUTER_PRIO; rprio = PAREN_INNER_PRIO;
|
||
goto maybe_reduce;
|
||
case ')':
|
||
lprio = PAREN_INNER_PRIO; rprio = PAREN_OUTER_PRIO;
|
||
goto maybe_reduce;
|
||
case ':':
|
||
lprio = COND_PRIO; rprio = COND_PRIO;
|
||
goto maybe_reduce;
|
||
case '?':
|
||
lprio = COND_PRIO + 1; rprio = COND_PRIO;
|
||
goto maybe_reduce;
|
||
binop:
|
||
flags = LEFT_OPERAND_REQUIRED|RIGHT_OPERAND_REQUIRED;
|
||
rprio = lprio + 1;
|
||
goto maybe_reduce;
|
||
default:
|
||
cpp_error (pfile, "invalid character in #if");
|
||
goto syntax_error;
|
||
}
|
||
|
||
set_value:
|
||
/* Push a value onto the stack. */
|
||
if (top->flags & HAVE_VALUE)
|
||
{
|
||
cpp_error (pfile, "syntax error in #if");
|
||
goto syntax_error;
|
||
}
|
||
top->flags |= HAVE_VALUE;
|
||
continue;
|
||
|
||
maybe_reduce:
|
||
/* Push an operator, and check if we can reduce now. */
|
||
while (top->rprio > lprio)
|
||
{
|
||
long v1 = top[-1].value, v2 = top[0].value;
|
||
int unsigned1 = top[-1].unsignedp, unsigned2 = top[0].unsignedp;
|
||
top--;
|
||
if ((top[1].flags & LEFT_OPERAND_REQUIRED)
|
||
&& ! (top[0].flags & HAVE_VALUE))
|
||
{
|
||
cpp_error (pfile, "syntax error - missing left operand");
|
||
goto syntax_error;
|
||
}
|
||
if ((top[1].flags & RIGHT_OPERAND_REQUIRED)
|
||
&& ! (top[1].flags & HAVE_VALUE))
|
||
{
|
||
cpp_error (pfile, "syntax error - missing right operand");
|
||
goto syntax_error;
|
||
}
|
||
/* top[0].value = (top[1].op)(v1, v2);*/
|
||
switch (top[1].op)
|
||
{
|
||
case '+':
|
||
if (!(top->flags & HAVE_VALUE))
|
||
{ /* Unary '+' */
|
||
top->value = v2;
|
||
top->unsignedp = unsigned2;
|
||
top->flags |= HAVE_VALUE;
|
||
}
|
||
else
|
||
{
|
||
top->value = v1 + v2;
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
if (! top->unsignedp
|
||
&& ! possible_sum_sign (v1, v2, top->value))
|
||
integer_overflow (pfile);
|
||
}
|
||
break;
|
||
case '-':
|
||
if (!(top->flags & HAVE_VALUE))
|
||
{ /* Unary '-' */
|
||
top->value = - v2;
|
||
if ((top->value & v2) < 0 && ! unsigned2)
|
||
integer_overflow (pfile);
|
||
top->unsignedp = unsigned2;
|
||
top->flags |= HAVE_VALUE;
|
||
}
|
||
else
|
||
{ /* Binary '-' */
|
||
top->value = v1 - v2;
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
if (! top->unsignedp
|
||
&& ! possible_sum_sign (top->value, v2, v1))
|
||
integer_overflow (pfile);
|
||
}
|
||
break;
|
||
case '*':
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
if (top->unsignedp)
|
||
top->value = (unsigned long) v1 * v2;
|
||
else
|
||
{
|
||
top->value = v1 * v2;
|
||
if (v1
|
||
&& (top->value / v1 != v2
|
||
|| (top->value & v1 & v2) < 0))
|
||
integer_overflow (pfile);
|
||
}
|
||
break;
|
||
case '/':
|
||
if (v2 == 0)
|
||
{
|
||
cpp_error (pfile, "division by zero in #if");
|
||
v2 = 1;
|
||
}
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
if (top->unsignedp)
|
||
top->value = (unsigned long) v1 / v2;
|
||
else
|
||
{
|
||
top->value = v1 / v2;
|
||
if ((top->value & v1 & v2) < 0)
|
||
integer_overflow (pfile);
|
||
}
|
||
break;
|
||
case '%':
|
||
if (v2 == 0)
|
||
{
|
||
cpp_error (pfile, "division by zero in #if");
|
||
v2 = 1;
|
||
}
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
if (top->unsignedp)
|
||
top->value = (unsigned long) v1 % v2;
|
||
else
|
||
top->value = v1 % v2;
|
||
break;
|
||
case '!':
|
||
if (top->flags & HAVE_VALUE)
|
||
{
|
||
cpp_error (pfile, "syntax error");
|
||
goto syntax_error;
|
||
}
|
||
top->value = ! v2;
|
||
top->unsignedp = 0;
|
||
top->flags |= HAVE_VALUE;
|
||
break;
|
||
case '~':
|
||
if (top->flags & HAVE_VALUE)
|
||
{
|
||
cpp_error (pfile, "syntax error");
|
||
goto syntax_error;
|
||
}
|
||
top->value = ~ v2;
|
||
top->unsignedp = unsigned2;
|
||
top->flags |= HAVE_VALUE;
|
||
break;
|
||
case '<': COMPARE(<); break;
|
||
case '>': COMPARE(>); break;
|
||
case LEQ: COMPARE(<=); break;
|
||
case GEQ: COMPARE(>=); break;
|
||
case EQUAL:
|
||
top->value = (v1 == v2);
|
||
top->unsignedp = 0;
|
||
break;
|
||
case NOTEQUAL:
|
||
top->value = (v1 != v2);
|
||
top->unsignedp = 0;
|
||
break;
|
||
case LSH:
|
||
top->unsignedp = unsigned1;
|
||
if (v2 < 0 && ! unsigned2)
|
||
top->value = right_shift (pfile, v1, unsigned1, -v2);
|
||
else
|
||
top->value = left_shift (pfile, v1, unsigned1, v2);
|
||
break;
|
||
case RSH:
|
||
top->unsignedp = unsigned1;
|
||
if (v2 < 0 && ! unsigned2)
|
||
top->value = left_shift (pfile, v1, unsigned1, -v2);
|
||
else
|
||
top->value = right_shift (pfile, v1, unsigned1, v2);
|
||
break;
|
||
#define LOGICAL(OP) \
|
||
top->value = v1 OP v2;\
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
case '&': LOGICAL(&); break;
|
||
case '^': LOGICAL(^); break;
|
||
case '|': LOGICAL(|); break;
|
||
case ANDAND:
|
||
top->value = v1 && v2; top->unsignedp = 0; break;
|
||
case OROR:
|
||
top->value = v1 || v2; top->unsignedp = 0; break;
|
||
case ',':
|
||
if (CPP_PEDANTIC (pfile))
|
||
cpp_pedwarn (pfile, "comma operator in operand of `#if'");
|
||
top->value = v2;
|
||
top->unsignedp = unsigned2;
|
||
break;
|
||
case '(': case '?':
|
||
cpp_error (pfile, "syntax error in #if");
|
||
goto syntax_error;
|
||
case ':':
|
||
if (top[0].op != '?')
|
||
{
|
||
cpp_error (pfile,
|
||
"syntax error ':' without preceding '?'");
|
||
goto syntax_error;
|
||
}
|
||
else if (! (top[1].flags & HAVE_VALUE)
|
||
|| !(top[-1].flags & HAVE_VALUE)
|
||
|| !(top[0].flags & HAVE_VALUE))
|
||
{
|
||
cpp_error (pfile, "bad syntax for ?: operator");
|
||
goto syntax_error;
|
||
}
|
||
else
|
||
{
|
||
top--;
|
||
top->value = top->value ? v1 : v2;
|
||
top->unsignedp = unsigned1 || unsigned2;
|
||
}
|
||
break;
|
||
case ')':
|
||
if ((top[1].flags & HAVE_VALUE)
|
||
|| ! (top[0].flags & HAVE_VALUE)
|
||
|| top[0].op != '('
|
||
|| (top[-1].flags & HAVE_VALUE))
|
||
{
|
||
cpp_error (pfile, "mismatched parentheses in #if");
|
||
goto syntax_error;
|
||
}
|
||
else
|
||
{
|
||
top--;
|
||
top->value = v1;
|
||
top->unsignedp = unsigned1;
|
||
top->flags |= HAVE_VALUE;
|
||
}
|
||
break;
|
||
default:
|
||
fprintf (stderr,
|
||
top[1].op >= ' ' && top[1].op <= '~'
|
||
? "unimplemented operator '%c'\n"
|
||
: "unimplemented operator '\\%03o'\n",
|
||
top[1].op);
|
||
}
|
||
}
|
||
if (op.op == 0)
|
||
{
|
||
if (top != stack)
|
||
cpp_error (pfile, "internal error in #if expression");
|
||
if (stack != init_stack)
|
||
free (stack);
|
||
return top->value;
|
||
}
|
||
top++;
|
||
|
||
/* Check for and handle stack overflow. */
|
||
if (top == limit)
|
||
{
|
||
struct operation *new_stack;
|
||
int old_size = (char*)limit - (char*)stack;
|
||
int new_size = 2 * old_size;
|
||
if (stack != init_stack)
|
||
new_stack = (struct operation*) xrealloc (stack, new_size);
|
||
else
|
||
{
|
||
new_stack = (struct operation*) xmalloc (new_size);
|
||
bcopy ((char *) stack, (char *) new_stack, old_size);
|
||
}
|
||
stack = new_stack;
|
||
top = (struct operation*)((char*) new_stack + old_size);
|
||
limit = (struct operation*)((char*) new_stack + new_size);
|
||
}
|
||
|
||
top->flags = flags;
|
||
top->rprio = rprio;
|
||
top->op = op.op;
|
||
}
|
||
syntax_error:
|
||
if (stack != init_stack)
|
||
free (stack);
|
||
skip_rest_of_line (pfile);
|
||
return 0;
|
||
}
|