1 // RUN: %clang_cc1 -fsyntax-only %s --std=c++17 -verify 2 // This is a reduction of GH57370 and GH58028, originally appearing 3 // in libstdc++'s variant code. 4 5 struct V1 {}; 6 struct V2 : V1 { 7 int &a; 8 }; 9 10 template <class T> using void_t = void; 11 12 template <class T> struct X { T x; }; 13 14 template <class T1, class T2, class = void> struct Variant { 15 Variant() = delete; // expected-note {{deleted here}} 16 }; 17 18 template <class T1, class T2> 19 struct Variant<T1, T2, void_t<decltype(X<T2>{T1()})>> {}; 20 f()21void f() { 22 Variant<V1, V1>(); 23 Variant<V1, V2>(); // expected-error {{call to deleted constructor}} 24 } 25