struct X {
int v;
typedef int t;
void f(X);
};
struct YA {
int value;
typedef int type;
};
struct Z {
void f(Z);
};
template<typename T> struct C : X, T {
using T::value;
using typename T::type;
using X::v;
using typename X::t;
};
template<typename T> struct D : X, T {
using T::value;
using typename T::type;
using X::v;
using typename X::t;
};
template<typename T> struct E : X, T {
using T::value;
using typename T::type;
using X::v;
using typename X::t;
};
template<typename T> struct F : X, T {
using T::value;
using typename T::type;
using X::v;
using typename X::t;
};
// Force instantiation.
typedef C<YA>::type I;
typedef D<YA>::type I;
typedef E<YA>::type I;
typedef F<YA>::type I;
#if __cplusplus >= 201702L
template<typename ...T> struct G : T... {
using T::f...;
};
using Q = decltype(G<X, Z>());
#endif