xref: /llvm-project/clang/test/SemaTemplate/pr52909.cpp (revision ba15d186e5cef2620d562c6c9d9a6d570382cd0a)
1 // RUN: %clang_cc1 -std=c++20 -verify %s
2 // RUN: %clang_cc1 -std=c++23 -verify %s
3 
4 namespace PR52905 {
5 template <class> concept C = true;
6 
7 struct A {
8   int begin();
9   int begin() const;
10 };
11 
12 template <class T>
13 concept Beginable = requires (T t) {
14   { t.begin } -> C;
15   // expected-note@-1 {{because 't.begin' would be invalid: reference to non-static member function must be called}}
16 };
17 
18 static_assert(Beginable<A>); // expected-error {{static assertion failed}}
19                              // expected-note@-1 {{does not satisfy 'Beginable'}}
20 } // namespace PR52905
21 
22 namespace PR52909a {
23 
24 template<class> constexpr bool B = true;
25 template<class T> concept True = B<T>;
26 
27 template <class T>
foo(T t)28 int foo(T t) requires requires { // expected-note {{candidate template ignored: constraints not satisfied}}
29     {t.begin} -> True; // expected-note {{because 't.begin' would be invalid: reference to non-static member function must be called}}
30 }
31 {}
32 
33 struct A { int begin(); };
34 auto x = foo(A()); // expected-error {{no matching function for call to 'foo'}}
35 
36 } // namespace PR52909a
37 
38 namespace PR52909b {
39 
40 template<class> concept True = true;
41 
42 template<class T> concept C = requires {
43     { T::begin } -> True; // expected-note {{because 'T::begin' would be invalid: reference to overloaded function could not be resolved}}
44 };
45 
46 struct A {
47     static void begin(int);
48     static void begin(double);
49 };
50 
51 static_assert(C<A>); // expected-error {{static assertion failed}}
52   // expected-note@-1 {{because 'A' does not satisfy 'C'}}
53 
54 } // namespace PR52909b
55 
56 namespace PR53075 {
57 template<class> concept True = true;
58 
59 template<class T> concept C = requires {
60     { &T::f } -> True; // expected-note {{because '&T::f' would be invalid: reference to overloaded function could not be resolved}}
61 };
62 
63 struct S {
64     int *f();
65     int *f() const;
66 };
67 
68 static_assert(C<S>); // expected-error {{static assertion failed}}
69   // expected-note@-1 {{because 'S' does not satisfy 'C'}}
70 
71 } // namespace PR53075
72