34 lines
1.1 KiB
Diff
34 lines
1.1 KiB
Diff
Fix a regression in GCC 10/11/12 where some union structures
|
|
could get miscompiled when optimizations are enabled:
|
|
|
|
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105860
|
|
|
|
Taken from upstream:
|
|
|
|
https://gcc.gnu.org/g:16afe2e2862f3dd93c711d7f8d436dee23c6c34d
|
|
|
|
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
|
|
index 09d951a261b..420329f63f6 100644
|
|
--- a/gcc/tree-sra.c
|
|
+++ b/gcc/tree-sra.c
|
|
@@ -1647,7 +1647,18 @@ build_ref_for_offset (location_t loc, tree base, poly_int64 offset,
|
|
static tree
|
|
build_reconstructed_reference (location_t, tree base, struct access *model)
|
|
{
|
|
- tree expr = model->expr, prev_expr = NULL;
|
|
+ tree expr = model->expr;
|
|
+ /* We have to make sure to start just below the outermost union. */
|
|
+ tree start_expr = expr;
|
|
+ while (handled_component_p (expr))
|
|
+ {
|
|
+ if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == UNION_TYPE)
|
|
+ start_expr = expr;
|
|
+ expr = TREE_OPERAND (expr, 0);
|
|
+ }
|
|
+
|
|
+ expr = start_expr;
|
|
+ tree prev_expr = NULL_TREE;
|
|
while (!types_compatible_p (TREE_TYPE (expr), TREE_TYPE (base)))
|
|
{
|
|
if (!handled_component_p (expr))
|