--- old/src/share/vm/gc/g1/g1ConcurrentMark.cpp	2016-02-10 09:36:31.451236050 +0100
+++ new/src/share/vm/gc/g1/g1ConcurrentMark.cpp	2016-02-10 09:36:31.335236046 +0100
@@ -984,13 +984,11 @@
 };
 
 void G1ConcurrentMark::scanRootRegions() {
-  // Start of concurrent marking.
-  ClassLoaderDataGraph::clear_claimed_marks();
-
   // scan_in_progress() will have been set to true only if there was
   // at least one root region to scan. So, if it's false, we
   // should not attempt to do any further work.
   if (root_regions()->scan_in_progress()) {
+    assert(!has_aborted(), "Aborting before root region scanning is finished not supported.");
     GCTraceConcTime(Info, gc) tt("Concurrent Root Region Scan");
 
     _parallel_marking_threads = calc_parallel_marking_threads();