--- old/src/hotspot/share/gc/shared/referenceProcessor.cpp	2018-09-28 16:47:33.274815153 +0200
+++ new/src/hotspot/share/gc/shared/referenceProcessor.cpp	2018-09-28 16:47:33.132818413 +0200
@@ -284,7 +284,7 @@
 
   // First _prev_next ref actually points into DiscoveredList (gross).
   oop new_next;
-  if (_next_discovered == _current_discovered) {
+  if (oopDesc::unsafe_equals(_next_discovered, _current_discovered)) {
     // At the end of the list, we should make _prev point to itself.
     // If _ref is the first ref, then _prev_next will be in the DiscoveredList,
     // and _prev will be NULL.
@@ -474,7 +474,7 @@
 ReferenceProcessor::clear_discovered_references(DiscoveredList& refs_list) {
   oop obj = NULL;
   oop next = refs_list.head();
-  while (next != obj) {
+  while (! oopDesc::unsafe_equals(next, obj)) {
     obj = next;
     next = java_lang_ref_Reference::discovered(obj);
     java_lang_ref_Reference::set_discovered_raw(obj, NULL);
@@ -746,7 +746,7 @@
         ref_lists[to_idx].inc_length(refs_to_move);
 
         // Remove the chain from the from list.
-        if (move_tail == new_head) {
+        if (oopDesc::unsafe_equals(move_tail, new_head)) {
           // We found the end of the from list.
           ref_lists[from_idx].set_head(NULL);
         } else {