1 // RUN: %clang_cc1 -triple x86_64-apple-darwin9 %s -std=c++20 -fsyntax-only -Wignored-qualifiers -Wno-error=return-type -verify -fblocks -Wno-unreachable-code -Wno-unused-value
2 #ifndef STD_COROUTINE_H
3 #define STD_COROUTINE_H
4 
5 namespace std {
6 
7 template <class Ret, typename... T>
8 struct coroutine_traits { using promise_type = typename Ret::promise_type; };
9 
10 template <class Promise = void>
11 struct coroutine_handle {
12   static coroutine_handle from_address(void *) noexcept;
13 };
14 template <>
15 struct coroutine_handle<void> {
16   template <class PromiseType>
17   coroutine_handle(coroutine_handle<PromiseType>) noexcept;
18   static coroutine_handle from_address(void *);
19 };
20 
21 struct suspend_always {
22   bool await_ready() noexcept { return false; }
23   void await_suspend(coroutine_handle<>) noexcept {}
24   void await_resume() noexcept {}
25 };
26 
27 struct suspend_never {
28   bool await_ready() noexcept { return true; }
29   void await_suspend(coroutine_handle<>) noexcept {}
30   void await_resume() noexcept {}
31 };
32 
33 } // namespace std
34 
35 #endif // STD_COROUTINE_H
36