| // { dg-do compile { target c++2a } } | |
| // { dg-additional-options "-fconcepts-ts" } | |
| template<class T> concept bool C1() { return false; } | |
| template<C1 T> concept bool C2() { return true; } // { dg-error "cannot be constrained" } | |
| void f(C2 x) { | |
| } | |
| struct A {} a; | |
| int main() { | |
| f(a); | |
| } |