--- old/src/share/vm/oops/instanceRefKlass.hpp	2010-10-28 13:58:21.000000000 +0200
+++ new/src/share/vm/oops/instanceRefKlass.hpp	2010-10-28 13:58:21.000000000 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,6 +22,11 @@
  *
  */
 
+#ifndef SHARE_VM_OOPS_INSTANCEREFKLASS_HPP
+#define SHARE_VM_OOPS_INSTANCEREFKLASS_HPP
+
+#include "oops/instanceKlass.hpp"
+
 // An instanceRefKlass is a specialized instanceKlass for Java
 // classes that are subclasses of java/lang/ref/Reference.
 //
@@ -93,3 +98,5 @@
   // Verification
   void oop_verify_on(oop obj, outputStream* st);
 };
+
+#endif // SHARE_VM_OOPS_INSTANCEREFKLASS_HPP