| // This file contains references to sections of the Coroutines TS, which can be |
| // found at http://wg21.link/coroutines. |
| |
| // RUN: %clang_cc1 -std=c++20 -verify %s -fcxx-exceptions -fexceptions -Wunused-result |
| |
| namespace std { |
| |
| template<typename ...T> |
| struct coroutine_traits { |
| struct promise_type {}; |
| }; |
| |
| template <> struct coroutine_traits<void>; // expected-note {{forward declaration of 'std::coroutine_traits<void>'}} |
| } // namespace std |
| |
| void uses_forward_declaration() { |
| co_return; // expected-error {{this function cannot be a coroutine: missing definition of specialization 'coroutine_traits<void>'}} |
| } |
