--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp	Wed Jul 05 16:49:07 2017 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp	Wed Mar 18 11:37:48 2009 -0400
@@ -1087,6 +1087,7 @@
 
   assert(_g1->used_regions() == _g1->recalculate_used_regions(),
          "sanity");
+  assert(_g1->used() == _g1->recalculate_used(), "sanity");
 
   double s_w_t_ms = (start_time_sec - _stop_world_start) * 1000.0;
   _all_stop_world_times_ms->add(s_w_t_ms);