gcc/testsuite/g++.dg/concepts/explicit-spec3.C

   1 // { dg-options "-std=c++17 -fconcepts" }
   2
   3 template<typename T>
   4   concept bool C() { return __is_class(T); }
   5
   6 template<C T> struct S;
   7
   8 struct X { };
   9
  10 // Not a valid explicit specialization, int does not satisfy C.
  11 template<> struct S<int> { }; // { dg-error "constraint" }
  12
  13 int main() { }