1 // PR c++/100032 2 // { dg-do compile { target c++11 } } 3 4 template <template<class> class> struct X { }; 5 template <class> struct Y { }; 6 template <class T> using Z = const Y<T>; 7 8 template <class T> using W = Z<T>; 9 using U = X<Z>; 10 using U = X<W>; 11 12 using T = X<Y>; 13 using T = X<Z>; // { dg-error "conflicting declaration" } 14