Hi,
this patch fixes handling of TYPE_USER_ALIGN. I tried to drop it
completely from LTO streaming and clear it in free lang data but it
breaks one ubsan testcase:
FAIL: c-c++-common/ubsan/pr63802.c -O2 -flto -fno-use-linker-plugin
-flto-partition=none output pattern test
FAIL: c-c++-common/ubsan/pr63802.c -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects output pattern test
lto-bootstrapped/regtested x86_64-linux, OK?
Honza
* tree.c (fld_type_variant_equal_p): Test user align flag.
(flt_type_variant): Copy user align flag.
(fld_incomplete_type_of): Clear it.
Index: tree.c
===================================================================
--- tree.c (revision 265914)
+++ tree.c (working copy)
@@ -5109,7 +5109,8 @@ fld_type_variant_equal_p (tree t, tree v
/* We want to match incomplete variants with complete types.
In this case we need to ignore alignment. */
|| ((!RECORD_OR_UNION_TYPE_P (t) || COMPLETE_TYPE_P (v))
- && TYPE_ALIGN (t) != TYPE_ALIGN (v))
+ && (TYPE_ALIGN (t) != TYPE_ALIGN (v)
+ || TYPE_USER_ALIGN (t) != TYPE_USER_ALIGN (v)))
|| fld_simplified_type_name (t) != fld_simplified_type_name (v)
|| !attribute_list_equal (TYPE_ATTRIBUTES (t),
TYPE_ATTRIBUTES (v)))
@@ -5140,7 +5141,10 @@ fld_type_variant (tree first, tree t, st
/* Variants of incomplete types should have alignment
set to BITS_PER_UNIT. Do not copy the actual alignment. */
if (!RECORD_OR_UNION_TYPE_P (v) || COMPLETE_TYPE_P (v))
- SET_TYPE_ALIGN (v, TYPE_ALIGN (t));
+ {
+ SET_TYPE_ALIGN (v, TYPE_ALIGN (t));
+ TYPE_USER_ALIGN (v) = TYPE_USER_ALIGN (t);
+ }
gcc_checking_assert (fld_type_variant_equal_p (t,v));
add_tree_to_fld_list (v, fld);
return v;
@@ -5194,6 +5198,7 @@ fld_incomplete_type_of (tree t, struct f
TYPE_SIZE (copy) = NULL;
SET_TYPE_MODE (copy, VOIDmode);
SET_TYPE_ALIGN (copy, BITS_PER_UNIT);
+ TYPE_USER_ALIGN (copy) = 0;
TYPE_SIZE_UNIT (copy) = NULL;
TYPE_CANONICAL (copy) = TYPE_CANONICAL (t);
TYPE_TYPELESS_STORAGE (copy) = 0;
