diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 830517d3b4e..1cba951f45e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2007-06-09  Daniel Berlin  <dberlin@dberlin.org>
+
+	* tree-data-ref.c (dr_may_alias_p): Check that decl_a != decl_b,
+	and allow DECL_P here.
+
 2007-06-09  Zdenek Dvorak  <dvorakz@suse.cz>
 
 	* tree-scalar-evolution.c (follow_ssa_edge_in_rhs,
diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index 99f8fd2b91f..4d96311ae6c 100644
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -1176,8 +1176,9 @@ dr_may_alias_p (struct data_reference *a, struct data_reference *b)
 
   if (TYPE_RESTRICT (type_a) && TYPE_RESTRICT (type_b) 
       && (!DR_IS_READ (a) || !DR_IS_READ (b))
-      && decl_a && TREE_CODE (decl_a) == PARM_DECL
-      && decl_b && TREE_CODE (decl_b) == PARM_DECL
+      && decl_a && DECL_P (decl_a)
+      && decl_b && DECL_P (decl_b)
+      && decl_a != decl_b
       && TREE_CODE (DECL_CONTEXT (decl_a)) == FUNCTION_DECL
       && DECL_CONTEXT (decl_a) == DECL_CONTEXT (decl_b))
     return false;