--- a/truffle/com.oracle.truffle.object.basic/src/com/oracle/truffle/object/basic/DefaultStrategy.java	Mon Sep 14 11:14:58 2015 +0200
+++ b/truffle/com.oracle.truffle.object.basic/src/com/oracle/truffle/object/basic/DefaultStrategy.java	Sat Sep 12 22:03:23 2015 +0200
@@ -41,8 +41,8 @@
 
     private static boolean assertLocationInRange(Shape shape, Location location) {
         BasicLayout layout = (BasicLayout) shape.getLayout();
-        assert (shape.getPrimitiveFieldSize() + ((LocationImpl) location).primitiveFieldCount() <= layout.getPrimitiveFieldCount());
-        assert (shape.getObjectFieldSize() + ((LocationImpl) location).objectFieldCount() <= layout.getObjectFieldCount());
+        assert (((ShapeImpl) shape).getPrimitiveFieldSize() + ((LocationImpl) location).primitiveFieldCount() <= layout.getPrimitiveFieldCount());
+        assert (((ShapeImpl) shape).getObjectFieldSize() + ((LocationImpl) location).objectFieldCount() <= layout.getObjectFieldCount());
         return true;
     }