std :: async::coro
Macro ASYNC_END
#define ASYNC_END std::panic_at("std/async: coroutine reached ASYNC_END without ASYNC_RETURN", __FILE__, __LINE__); return Poll::pending()std :: async::coro
#define ASYNC_END std::panic_at("std/async: coroutine reached ASYNC_END without ASYNC_RETURN", __FILE__, __LINE__); return Poll::pending()