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author | rms <rms@138bc75d-0d04-0410-961f-82ee72b054a4> | 1992-09-17 21:11:17 +0000 |
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committer | rms <rms@138bc75d-0d04-0410-961f-82ee72b054a4> | 1992-09-17 21:11:17 +0000 |
commit | d27efafbf18c541ac8da26aa8d1cb77769fa1df8 (patch) | |
tree | 67c9ce01a89e18445ea9e479980e6fbe8213a638 /gcc/cexp.y | |
parent | 34a5ca59fb3a0e5d8128ed7f937e855813799041 (diff) | |
download | gcc-d27efafbf18c541ac8da26aa8d1cb77769fa1df8.tar.gz |
(parse_escape): Diagnose '\x' with no digits.
Diagnose integer overflow when parsing \x escapes.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@2147 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/cexp.y')
-rw-r--r-- | gcc/cexp.y | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/gcc/cexp.y b/gcc/cexp.y index c0fbca561b3..9530a37c3ce 100644 --- a/gcc/cexp.y +++ b/gcc/cexp.y @@ -803,23 +803,28 @@ parse_escape (string_ptr) } case 'x': { - register int i = 0; + register unsigned i = 0, overflow = 0, digits_found = 0, digit; for (;;) { c = *(*string_ptr)++; if (c >= '0' && c <= '9') - i = (i << 4) + c - '0'; + digit = c - '0'; else if (c >= 'a' && c <= 'f') - i = (i << 4) + c - 'a' + 10; + digit = c - 'a' + 10; else if (c >= 'A' && c <= 'F') - i = (i << 4) + c - 'A' + 10; + digit = c - 'A' + 10; else { (*string_ptr)--; break; } + overflow |= i ^ (i << 4 >> 4); + i = (i << 4) + digit; + digits_found = 1; } - if ((i & ~((1 << BITS_PER_UNIT) - 1)) != 0) + if (!digits_found) + yyerror ("\\x used with no following hex digits"); + if (overflow | (i & ~((1 << BITS_PER_UNIT) - 1))) { i &= (1 << BITS_PER_UNIT) - 1; warning ("hex character constant does not fit in a byte"); |