--- old/src/hotspot/share/gc/serial/serialHeap.hpp	2019-03-28 22:45:26.231274661 +0100
+++ new/src/hotspot/share/gc/serial/serialHeap.hpp	2019-03-28 22:45:26.009267517 +0100
@@ -59,11 +59,6 @@
   virtual GrowableArray<GCMemoryManager*> memory_managers();
   virtual GrowableArray<MemoryPool*> memory_pools();
 
-  // override
-  virtual bool is_in_closed_subset(const void* p) const {
-    return is_in(p);
-  }
-
   DefNewGeneration* young_gen() const {
     assert(_young_gen->kind() == Generation::DefNew, "Wrong generation type");
     return static_cast<DefNewGeneration*>(_young_gen);