xref: /llvm-project/clang/test/CXX/temp/temp.constr/temp.constr.decl/p3.cpp (revision 67c608a9695496cfc9d3fdf9d0b12b554ac6b4df)
1 // RUN: %clang_cc1 -std=c++2a -x c++ -verify %s
2 
3 template<typename T>
4 struct X {
5     using Y = typename T::invalid;
6 };
7 
8 template<typename T>
9 concept Invalid = X<T>{};
10 
11 template<typename T>
12 concept False = false; // expected-note{{because 'false' evaluated to false}}
13 
14 template<typename T>
15 concept True = true;
16 
17 // TODO: Concepts: Uncomment trailing requires clauses here when we have correct substitution.
18 //template<True T>
19 //  requires False<T>
20 //void g1() requires Invalid<T>;
21 //
22 //using g1i = decltype(g1<int>());
23 
24 template<False T> // expected-note{{because 'int' does not satisfy 'False'}}
25   requires Invalid<T>
26 void g2(); // requires Invalid<T>;
27 // expected-note@-1{{candidate template ignored: constraints not satisfied [with T = int]}}
28 
29 using g2i = decltype(g2<int>());
30 // expected-error@-1{{no matching function for call to 'g2'}}