--- old/src/hotspot/share/gc/z/zMark.cpp	2019-02-19 14:38:57.682539210 +0100
+++ new/src/hotspot/share/gc/z/zMark.cpp	2019-02-19 14:38:57.497533251 +0100
@@ -129,8 +129,6 @@
   }
 
   virtual void do_thread(Thread* thread) {
-    ZRootsIteratorClosure::do_thread(thread);
-
     // Update thread local address bad mask
     ZThreadLocalData::set_address_bad_mask(thread, ZAddressBadMask);