The following fixes the LTO bootstrap miscompares on the branches.
They happen because type_hash_canon can end up returning different
types (a main variant or a variant type) dependent on whether
we garbage collected before or not.
The patch makes us never return a variant type from type_hash_canon
if we fed it a main variant (and vice versa).
LTO bootstrap running on the 4.9 branch, regular bootstrap and testing
running on x86_64-unknown-linux-gnu.
Richard.
2014-08-13 Richard Biener <rguent...@suse.de>
PR middle-end/62077
* tree.c (type_hash_eq): Do not treat main variants equal
to non-main-variants.
Index: gcc/tree.c
===================================================================
--- gcc/tree.c (revision 213814)
+++ gcc/tree.c (working copy)
@@ -6593,7 +6593,9 @@ type_hash_eq (const void *va, const void
|| !attribute_list_equal (TYPE_ATTRIBUTES (a->type),
TYPE_ATTRIBUTES (b->type))
|| (TREE_CODE (a->type) != COMPLEX_TYPE
- && TYPE_NAME (a->type) != TYPE_NAME (b->type)))
+ && TYPE_NAME (a->type) != TYPE_NAME (b->type))
+ || ((TYPE_MAIN_VARIANT (a->type) == TYPE_MAIN_VARIANT (a->type))
+ != (TYPE_MAIN_VARIANT (b->type) == TYPE_MAIN_VARIANT (b->type))))
return 0;
/* Be careful about comparing arrays before and after the element type
