| // { dg-do compile { target c++17_only } } |
| // { dg-options "-fconcepts" } |
| |
| template <class T1, class T2> class A { }; |
| |
| A<int, int> a; |
| A<double, float> a2; |
| A<double, double> a22; |
| |
| A<auto, auto> b = a; |
| A<auto, auto> b1 = a2; |
| |
| template <class T> concept bool C = __is_same_as (T, int); |
| |
| A<C,C> b2 = a; |
| A<C,C> b3 = a2; // { dg-error "" } |
| A<C,C> b32 = a22; // { dg-error "" } |
| |
| template <class T> concept bool C2() { return __is_enum (T); } |
| |
| enum E1 { }; |
| enum E2 { }; |
| |
| A<E1,E1> a3; |
| A<C2,C2> b4 = a3; |
| |
| A<E1,E2> a4; |
| A<C2,C2> b5 = a4; // { dg-error "" } |
