1 // RUN: %clang_cc1 -std=c++11 -verify %s 2 3 template<typename ...T> struct X { 4 void f(int); 5 void f(...); 6 static int n; 7 }; 8 9 template<typename T, typename U> using A = T; 10 11 // These definitions are OK, X<A<T, decltype(...)>...> is equivalent to X<T...> 12 // so this defines the member of the primary template. 13 template<typename ...T> 14 void X<A<T, decltype(f(T()))>...>::f(int) {} // expected-error {{undeclared}} 15 16 template<typename ...T> 17 int X<A<T, decltype(f(T()))>...>::n = 0; // expected-error {{undeclared}} 18 19 struct Y {}; void f(Y); 20 21 void g() { 22 // OK, substitution succeeds. 23 X<Y>().f(0); 24 X<Y>::n = 1; 25 26 // Error, substitution fails; this should not be treated as a SFINAE-able 27 // condition, so we don't select X<void>::f(...). 28 X<void>().f(0); // expected-note {{instantiation of}} 29 X<void>::n = 1; // expected-note {{instantiation of}} 30 } 31
