diff -r 73395f9cad54 -r 3868dde58ebb src/hotspot/share/gc/z/zCollectedHeap.cpp
--- a/src/hotspot/share/gc/z/zCollectedHeap.cpp	Tue Jul 02 12:24:26 2019 +0200
+++ b/src/hotspot/share/gc/z/zCollectedHeap.cpp	Mon Jun 10 13:04:12 2019 +0200
@@ -232,11 +232,11 @@
 }
 
 void ZCollectedHeap::object_iterate(ObjectClosure* cl) {
-  _heap.object_iterate(cl, true /* visit_referents */);
+  _heap.object_iterate(cl, true /* visit_weaks */);
 }
 
 void ZCollectedHeap::safe_object_iterate(ObjectClosure* cl) {
-  _heap.object_iterate(cl, true /* visit_referents */);
+  _heap.object_iterate(cl, true /* visit_weaks */);
 }
 
 HeapWord* ZCollectedHeap::block_start(const void* addr) const {