diff --git a/libstdc++-v3/include/bits/functional_hash.h b/libstdc++-v3/include/bits/functional_hash.h
index d94843f..a217f8a 100644
--- a/libstdc++-v3/include/bits/functional_hash.h
+++ b/libstdc++-v3/include/bits/functional_hash.h
@@ -36,6 +36,29 @@
 
 namespace std _GLIBCXX_VISIBILITY(default)
 {
+namespace __detail
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+  // Compute highest power of 2 lower or equal to __n.
+  template<size_t __n>
+    struct _Lowest_power_of_two
+    {
+      static const size_t __val
+        = _Lowest_power_of_two< (__n >> 1) >::__val + 1;
+    };
+
+  template<>
+    struct _Lowest_power_of_two<1>
+    { static const size_t __val = 0; };
+
+  template<>
+    struct _Lowest_power_of_two<0>
+    { static const size_t __val = 0; };
+
+_GLIBCXX_END_NAMESPACE_VERSION
+}
+
 _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
   /** @defgroup hashes Hashes
@@ -63,7 +86,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     {
       size_t
       operator()(_Tp* __p) const noexcept
-      { return reinterpret_cast<size_t>(__p); }
+      {
+	return reinterpret_cast<size_t>(__p)
+	  >> __detail::_Lowest_power_of_two<alignof(_Tp)>::__val;
+      }
     };
 
   // Explicit specializations for integer types.
diff --git a/libstdc++-v3/testsuite/20_util/hash/quality.cc b/libstdc++-v3/testsuite/20_util/hash/quality.cc
index af417ed..d9c72c7 100644
--- a/libstdc++-v3/testsuite/20_util/hash/quality.cc
+++ b/libstdc++-v3/testsuite/20_util/hash/quality.cc
@@ -164,9 +164,20 @@ quality_test()
     }
 }
 
+void
+pointer_quality_test()
+{
+  bool test __attribute__((unused)) = true;
+
+  double d1, d2;
+  std::hash<double*> dh;
+  VERIFY( dh(&d1) % sizeof(double) != dh(&d2) % sizeof(double) );
+}
+
 int
 main()
 {
   quality_test();
+  pointer_quality_test();
   return 0;
 }