--- old/src/hotspot/share/gc/serial/serialHeap.hpp	2017-10-18 14:02:29.609423958 +0200
+++ new/src/hotspot/share/gc/serial/serialHeap.hpp	2017-10-18 14:02:29.273423136 +0200
@@ -36,20 +36,20 @@
 public:
   SerialHeap(GenCollectorPolicy* policy);
 
-  Name kind() const {
+  virtual Name kind() const {
     return CollectedHeap::SerialHeap;
   }
 
-  const char* name() const {
+  virtual const char* name() const {
     return "Serial";
   }
 
   // override
-  bool is_in_closed_subset(const void* p) const {
+  virtual bool is_in_closed_subset(const void* p) const {
     return is_in(p);
   }
 
-  bool card_mark_must_follow_store() const {
+  virtual bool card_mark_must_follow_store() const {
     return false;
   }