| // { dg-do compile { target c++20 } } | |
| template <class T, class U> | |
| concept Concept2 = requires (T t, U u) // { dg-error "depends on itself" } | |
| { | |
| t += u; | |
| }; | |
| template <class T> | |
| concept Concept = Concept2 <T, T>; | |
| struct S | |
| { | |
| template <Concept T> | |
| constexpr S& operator += (T o); | |
| }; | |
| constexpr S operator * (S a, S b) | |
| { | |
| return a += b; // { dg-error "no match" } | |
| } |