Update phmap::Hash so that std::hash<Foo*> can be overridden - issue #168

parallel_hashmap/phmap.h

@@ -4426,7 +4426,9 @@ struct HashEq<T*>
         using is_transparent = void;
         template <class U>
         size_t operator()(const U& ptr) const {
-            return phmap::Hash<const T*>{}(HashEq::ToPtr(ptr));
+            // we want phmap::Hash<T*> and not phmap::Hash<const T*>
+            // so "struct std::hash<T*> " override works
+            return phmap::Hash<T*>{}((T*)(uintptr_t)HashEq::ToPtr(ptr));
         }
     };
 

parallel_hashmap/phmap_utils.h

@@ -164,16 +164,7 @@ struct Hash
         return _hash<T>(val);
     }
 };
-
-template <class T>
-struct Hash<T *>
-{
-    inline size_t operator()(const T *val) const noexcept
-    {
-        return static_cast<size_t>(reinterpret_cast<const uintptr_t>(val)); 
-    }
-};
-
+ 
 template<class ArgumentType, class ResultType>
 struct phmap_unary_function
 {