--- old/src/hotspot/share/gc/shared/referenceProcessor.cpp	2018-04-23 17:00:21.424538304 +0200
+++ new/src/hotspot/share/gc/shared/referenceProcessor.cpp	2018-04-23 17:00:21.138529389 +0200
@@ -383,13 +383,14 @@
 }
 
 void DiscoveredListIterator::load_ptrs(DEBUG_ONLY(bool allow_null_referent)) {
-  _discovered_addr = java_lang_ref_Reference::discovered_addr_raw(_ref);
-  oop discovered = java_lang_ref_Reference::discovered(_ref);
-  assert(_discovered_addr && oopDesc::is_oop_or_null(discovered),
+  _current_discovered_addr = java_lang_ref_Reference::discovered_addr_raw(_current_discovered);
+  oop discovered = java_lang_ref_Reference::discovered(_current_discovered);
+  assert(_current_discovered_addr && oopDesc::is_oop_or_null(discovered),
          "Expected an oop or NULL for discovered field at " PTR_FORMAT, p2i(discovered));
   _next_discovered = discovered;
-  _referent_addr = java_lang_ref_Reference::referent_addr_raw(_ref);
-  _referent = java_lang_ref_Reference::referent(_ref);
+
+  _referent_addr = java_lang_ref_Reference::referent_addr_raw(_current_discovered);
+  _referent = java_lang_ref_Reference::referent(_current_discovered);
   assert(Universe::heap()->is_in_reserved_or_null(_referent),
          "Wrong oop found in java.lang.Reference object");
   assert(allow_null_referent ?
@@ -401,12 +402,12 @@
 }
 
 void DiscoveredListIterator::remove() {
-  assert(oopDesc::is_oop(_ref), "Dropping a bad reference");
-  RawAccess<>::oop_store(_discovered_addr, oop(NULL));
+  assert(oopDesc::is_oop(_current_discovered), "Dropping a bad reference");
+  RawAccess<>::oop_store(_current_discovered_addr, oop(NULL));
 
   // First _prev_next ref actually points into DiscoveredList (gross).
   oop new_next;
-  if (_next_discovered == _ref) {
+  if (_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.
--- old/src/hotspot/share/gc/shared/referenceProcessor.hpp	2018-04-23 17:00:22.592574713 +0200
+++ new/src/hotspot/share/gc/shared/referenceProcessor.hpp	2018-04-23 17:00:22.311565954 +0200
@@ -78,11 +78,13 @@
   DiscoveredList&    _refs_list;
   HeapWord*          _prev_discovered_addr;
   oop                _prev_discovered;
-  oop                _ref;
-  HeapWord*          _discovered_addr;
+  oop                _current_discovered;
+  HeapWord*          _current_discovered_addr;
   oop                _next_discovered;
+
   HeapWord*          _referent_addr;
   oop                _referent;
+
   OopClosure*        _keep_alive;
   BoolObjectClosure* _is_alive;
 
@@ -101,10 +103,10 @@
                                 BoolObjectClosure* is_alive);
 
   // End Of List.
-  inline bool has_next() const { return _ref != NULL; }
+  inline bool has_next() const { return _current_discovered != NULL; }
 
   // Get oop to the Reference object.
-  inline oop obj() const { return _ref; }
+  inline oop obj() const { return _current_discovered; }
 
   // Get oop to the referent object.
   inline oop referent() const { return _referent; }
@@ -123,8 +125,8 @@
 
   // Move to the next discovered reference.
   inline void next() {
-    _prev_discovered_addr = _discovered_addr;
-    _prev_discovered = _ref;
+    _prev_discovered_addr = _current_discovered_addr;
+    _prev_discovered = _current_discovered;
     move_to_next();
   }
 
@@ -150,13 +152,13 @@
   )
 
   inline void move_to_next() {
-    if (_ref == _next_discovered) {
+    if (_current_discovered == _next_discovered) {
       // End of the list.
-      _ref = NULL;
+      _current_discovered = NULL;
     } else {
-      _ref = _next_discovered;
+      _current_discovered = _next_discovered;
     }
-    assert(_ref != _first_seen, "cyclic ref_list found");
+    assert(_current_discovered != _first_seen, "cyclic ref_list found");
     NOT_PRODUCT(_processed++);
   }
 };
--- old/src/hotspot/share/gc/shared/referenceProcessor.inline.hpp	2018-04-23 17:00:23.763611215 +0200
+++ new/src/hotspot/share/gc/shared/referenceProcessor.inline.hpp	2018-04-23 17:00:23.476602269 +0200
@@ -53,7 +53,7 @@
   _refs_list(refs_list),
   _prev_discovered_addr(refs_list.adr_head()),
   _prev_discovered(NULL),
-  _ref(refs_list.head()),
+  _current_discovered(refs_list.head()),
 #ifdef ASSERT
   _first_seen(refs_list.head()),
 #endif