diff -r a837fa3d3f86 -r ef57c43512d6 src/share/vm/memory/cardTableModRefBS.cpp
--- a/src/share/vm/memory/cardTableModRefBS.cpp	Thu Jun 13 11:16:38 2013 -0700
+++ b/src/share/vm/memory/cardTableModRefBS.cpp	Thu Jun 13 22:02:40 2013 -0700
@@ -412,7 +412,7 @@
   }
   // Touch the last card of the covered region to show that it
   // is committed (or SEGV).
-  debug_only(*byte_for(_covered[ind].last());)
+  debug_only((void) (*byte_for(_covered[ind].last()));)
   debug_only(verify_guard();)
 }