diff options
Diffstat (limited to 'gcc/alias.c')
| -rw-r--r-- | gcc/alias.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/gcc/alias.c b/gcc/alias.c index b8661d7b6bd..ce358c41d35 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -507,6 +507,8 @@ get_alias_set (tree t) /* If we haven't computed the actual alias set, do it now. */ if (DECL_POINTER_ALIAS_SET (decl) == -2) { + tree pointed_to_type = TREE_TYPE (TREE_TYPE (decl)); + /* No two restricted pointers can point at the same thing. However, a restricted pointer can point at the same thing as an unrestricted pointer, if that unrestricted pointer @@ -515,11 +517,22 @@ get_alias_set (tree t) alias set for the type pointed to by the type of the decl. */ HOST_WIDE_INT pointed_to_alias_set - = get_alias_set (TREE_TYPE (TREE_TYPE (decl))); + = get_alias_set (pointed_to_type); if (pointed_to_alias_set == 0) /* It's not legal to make a subset of alias set zero. */ DECL_POINTER_ALIAS_SET (decl) = 0; + else if (AGGREGATE_TYPE_P (pointed_to_type)) + /* For an aggregate, we must treat the restricted + pointer the same as an ordinary pointer. If we + were to make the type pointed to by the + restricted pointer a subset of the pointed-to + type, then we would believe that other subsets + of the pointed-to type (such as fields of that + type) do not conflict with the type pointed to + by the restricted pointer. */ + DECL_POINTER_ALIAS_SET (decl) + = pointed_to_alias_set; else { DECL_POINTER_ALIAS_SET (decl) = new_alias_set (); |