1 // { dg-options "-std=c++17 -fconcepts" }
4 int operator==(X, X) { return 0; }
7 concept bool C1() { return X(); }
10 void h(T) { } // OK until used.
14 h(0); // { dg-error "does not have|cannot call" }
18 concept bool C2() { return X() == X(); } // OK