1 files changed, 12 insertions, 0 deletions
diff --git a/gcc/tree-ssa-copyrename.c b/gcc/tree-ssa-copyrename.c
index 49225d09b20..4ef5b3dbd1c 100644
--- a/gcc/tree-ssa-copyrename.c
+++ b/gcc/tree-ssa-copyrename.c
@@ -261,6 +261,18 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
       return;
     }
 
+  /* Don't coalesce if the aliasing sets of the types are different.  */
+  if (POINTER_TYPE_P (TREE_TYPE (root1))
+      && POINTER_TYPE_P (TREE_TYPE (root2))
+      && get_alias_set (TREE_TYPE (TREE_TYPE (root1)))
+          != get_alias_set (TREE_TYPE (TREE_TYPE (root2))))
+    {
+      if (debug)
+	fprintf (debug, " : 2 different alasing sets. No coalesce.\n");
+      return;
+    }
+
+
   /* Merge the two partitions.  */
   p3 = partition_union (map->var_partition, p1, p2);