--- old/src/share/vm/gc/g1/g1ConcurrentMark.cpp	2016-02-25 12:30:42.700421321 -0500
+++ new/src/share/vm/gc/g1/g1ConcurrentMark.cpp	2016-02-25 12:30:41.752367827 -0500
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2016, 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
@@ -2271,7 +2271,7 @@
   SATBMarkQueueSet& satb_mq_set = JavaThread::satb_mark_queue_set();
   guarantee(has_overflown() ||
             satb_mq_set.completed_buffers_num() == 0,
-            "Invariant: has_overflown = %s, num buffers = %d",
+            "Invariant: has_overflown = %s, num buffers = " SIZE_FORMAT,
             BOOL_TO_STR(has_overflown()),
             satb_mq_set.completed_buffers_num());