--- a/hotspot/src/share/vm/oops/constantPool.cpp	Thu Mar 21 10:11:24 2013 -0700
+++ b/hotspot/src/share/vm/oops/constantPool.cpp	Thu Mar 21 10:13:56 2013 -0700
@@ -1852,6 +1852,7 @@
   switch (tag_at(index).value()) {
     case JVM_CONSTANT_Class :
       { Klass* k = klass_at(index, CATCH);
+        guarantee(k != NULL, "need klass");
         k->print_value_on(st);
         st->print(" {0x%lx}", (address)k);
       }