--- a/hotspot/src/share/vm/services/memoryService.cpp	Sat Mar 16 07:39:14 2013 -0700
+++ b/hotspot/src/share/vm/services/memoryService.cpp	Sat Mar 16 07:39:57 2013 -0700
@@ -240,6 +240,7 @@
 void MemoryService::add_generation_memory_pool(Generation* gen,
                                                MemoryManager* major_mgr,
                                                MemoryManager* minor_mgr) {
+  guarantee(gen != NULL, "No generation for memory pool");
   Generation::Name kind = gen->kind();
   int index = _pools_list->length();