diff options
| author | Jakub Jelinek <jakub@redhat.com> | 2014-10-31 12:18:13 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2014-10-31 12:18:13 +0100 |
| commit | c288810f69853733df4452f25b78baaae0350a6c (patch) | |
| tree | ff9d28eec53e7130189a016c309bdf94e61e8086 /gcc/tree-vrp.c | |
| parent | 6fd52b789342ed9e37869891e07cd445b8f3e0bd (diff) | |
| download | gcc-c288810f69853733df4452f25b78baaae0350a6c.zip gcc-c288810f69853733df4452f25b78baaae0350a6c.tar.gz gcc-c288810f69853733df4452f25b78baaae0350a6c.tar.bz2 | |
re PR sanitizer/63697 (-fsanitize=undefined doesn't detect some subtraction overflows)
PR sanitizer/63697
* tree-vrp.c (simplify_internal_call_using_ranges): For subcode ==
MINUS_EXPR, check overflow on vr0.min - vr1.max and vr0.max - vr1.min
instead of vr0.min - vr1.min and vr0.max - vr1.max.
* c-c++-common/ubsan/overflow-sub-3.c: New test.
From-SVN: r216962
Diffstat (limited to 'gcc/tree-vrp.c')
| -rw-r--r-- | gcc/tree-vrp.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c index 55c7f7f..fe67230 100644 --- a/gcc/tree-vrp.c +++ b/gcc/tree-vrp.c @@ -9538,8 +9538,10 @@ simplify_internal_call_using_ranges (gimple_stmt_iterator *gsi, gimple stmt) } else { - tree r1 = int_const_binop (subcode, vr0.min, vr1.min); - tree r2 = int_const_binop (subcode, vr0.max, vr1.max); + tree r1 = int_const_binop (subcode, vr0.min, + subcode == MINUS_EXPR ? vr1.max : vr1.min); + tree r2 = int_const_binop (subcode, vr0.max, + subcode == MINUS_EXPR ? vr1.min : vr1.max); if (r1 == NULL_TREE || TREE_OVERFLOW (r1) || r2 == NULL_TREE || TREE_OVERFLOW (r2)) return false; |