// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s namespace Old { template<template<class> class TT> struct X { }; template<class> struct Y { }; template<class T> using Z = Y<T>; X<Y> y; X<Z> z; using SameType = decltype(y); // expected-note {{here}} using SameType = decltype(z); // expected-error {{different types}} } namespace New { template<class T> struct X { }; template<class> struct Y { }; template<class T> using Z = Y<T>; X<Y<int>> y; X<Z<int>> z; using SameType = decltype(y); using SameType = decltype(z); // ok }