diff --git a/include/ext/__hash b/include/ext/__hash
index 04975bfd..c0523cce 100644
--- a/include/ext/__hash
+++ b/include/ext/__hash
@@ -19,7 +19,7 @@
 namespace __gnu_cxx {
 using namespace std;
 
-template <typename T> struct _LIBCPP_TYPE_VIS_ONLY hash : public std::hash<T>
+template <typename _Tp> struct _LIBCPP_TYPE_VIS_ONLY hash : public std::hash<_Tp>
     { };
 
 template <> struct _LIBCPP_TYPE_VIS_ONLY hash<const char*>
diff --git a/include/type_traits b/include/type_traits
index c4afe5e1..0ad7b7f2 100644
--- a/include/type_traits
+++ b/include/type_traits
@@ -1409,7 +1409,7 @@ template <class ..._Tp> using common_type_t = typename common_type<_Tp...>::type
 
 // is_assignable
 
-template<typename, typename T> struct __select_2nd { typedef T type; };
+template<typename, typename _Tp> struct __select_2nd { typedef _Tp type; };
 
 template <class _Tp, class _Arg>
 typename __select_2nd<decltype((_VSTD::declval<_Tp>() = _VSTD::declval<_Arg>())), true_type>::type