1 // { dg-options "-std=c++17 -fconcepts" }
2 
3 template<typename T>
Concept()4 concept bool Concept() {
5   return requires () {
6     typename T::member_type1;
7     typename T::member_type2;
8   };
9 }
10 
11 struct model {
12   using member_type1 = int;
13   using member_type2 = int;
14 };
15 
16 template<Concept C>
17 struct S {};
18 
19 S<model> s;
20