1 // { dg-do compile { target c++2a } }
2 
3 template <class T> struct A { static const int x = 42; };
4 
5 template <class Ta> concept A42 = A<Ta>::x == 42;
6 template <class Tv> concept Void = __is_same_as(Tv, void);
7 template <class Tb, class Ub> concept A42b = Void<Tb> || A42<Ub>;
8 template <class Tc> concept R42c = A42b<Tc, Tc&>;
9 
10 static_assert (R42c<void>);
11