| // RUN: %clang_cc1 -fsyntax-only -std=c++11 -verify %s |
| // RUN: %clang_cc1 -fsyntax-only -std=c++14 -verify %s |
| // RUN: %clang_cc1 -fsyntax-only -std=c++17 -verify %s |
| // RUN: %clang_cc1 -fsyntax-only -std=c++20 -verify=cxx20 %s |
| // expected-no-diagnostics |
| |
| struct Incomplete; |
| template <class T> struct Holder { T t; }; |
| |
| namespace DotFollowingFunctionName { |
| struct Good { |
| struct Nested { |
| int b; |
| } a; |
| }; |
| |
| struct Bad { |
| Holder<Incomplete> a(); |
| }; |
| |
| template <class T> |
| constexpr auto f(T t) -> decltype((t.a.b, true)) { return true; } |
| constexpr bool f(...) { return false; } |
| |
| static_assert(DotFollowingFunctionName::f(Good{}), ""); |
| static_assert(!DotFollowingFunctionName::f(Bad{}), ""); |
| |
| #if __cplusplus >= 202002L |
| template <class T> |
| concept C = requires(T t) { t.a.b; }; |
| // cxx20-note@-1 {{because 't.a.b' would be invalid: reference to non-static member function must be called}} |
| |
| static_assert(C<Good>); |
| static_assert(!C<Bad>); |
| static_assert(C<Bad>); // cxx20-error {{static assertion failed}} |
| // cxx20-note@-1 {{because 'Bad' does not satisfy 'C'}} |
| #endif |
| } // namespace DotFollowingFunctionName |
| |
| namespace DotFollowingPointer { |
| struct Good { |
| int begin(); |
| }; |
| using Bad = Holder<Incomplete> *; |
| |
| template <class T> |
| constexpr auto f(T t) -> decltype((t.begin(), true)) { return true; } |
| constexpr bool f(...) { return false; } |
| |
| static_assert(DotFollowingPointer::f(Good{}), ""); |
| static_assert(!DotFollowingPointer::f(Bad{}), ""); |
| |
| #if __cplusplus >= 202002L |
| template <class T> |
| concept C = requires(T t) { t.begin(); }; |
| // cxx20-note@-1 {{because 't.begin()' would be invalid: member reference type 'Holder<Incomplete> *' is a pointer}} |
| |
| static_assert(C<Good>); |
| static_assert(!C<Bad>); |
| static_assert(C<Bad>); // cxx20-error {{static assertion failed}} |
| // cxx20-note@-1 {{because 'Bad' (aka 'Holder<Incomplete> *') does not satisfy 'C'}} |
| #endif |
| } // namespace DotFollowingPointer |