Improve SHOW_MEMORY accounting

FdbVersionedMap.cpp

@@ -41,8 +41,10 @@ public:
   // not sealed.
   void addref() const { ++referenceCount; }
   void delref() const {
-    if (delref_no_destroy())
-      delete (Subclass *)this;
+    if (delref_no_destroy()) {
+      ((Subclass *)this)->~Subclass();
+      safe_free((void *)this, sizeof(Subclass));
+    }
   }
   bool delref_no_destroy() const { return !--referenceCount; }
   int32_t debugGetReferenceCount() const {
@@ -146,7 +148,8 @@ private:
 };
 
 template <class P, class... Args> Reference<P> makeReference(Args &&...args) {
-  return Reference<P>(new P(std::forward<Args>(args)...));
+  return Reference<P>(new (safe_malloc(sizeof(P)))
+                          P(std::forward<Args>(args)...));
 }
 
 template <class P>