diff options
Diffstat (limited to 'gcc/tree-ssa-dse.c')
| -rw-r--r-- | gcc/tree-ssa-dse.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/gcc/tree-ssa-dse.c b/gcc/tree-ssa-dse.c index 4cb8c0f83ac..8b7aea0e54e 100644 --- a/gcc/tree-ssa-dse.c +++ b/gcc/tree-ssa-dse.c @@ -248,6 +248,18 @@ compute_trims (ao_ref *ref, sbitmap live, int *trim_head, int *trim_tail, residual handling in mem* and str* functions is usually reasonably efficient. */ *trim_tail = last_orig - last_live; + + /* But don't trim away out of bounds accesses, as this defeats + proper warnings. + + We could have a type with no TYPE_SIZE_UNIT or we could have a VLA + where TYPE_SIZE_UNIT is not a constant. */ + if (*trim_tail + && TYPE_SIZE_UNIT (TREE_TYPE (ref->base)) + && TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (ref->base))) == INTEGER_CST + && compare_tree_int (TYPE_SIZE_UNIT (TREE_TYPE (ref->base)), + last_orig) <= 0) + *trim_tail = 0; } else *trim_tail = 0; |