#include <coroutine>
#include <memory>

struct task {
  struct promise_type {
    auto initial_suspend() noexcept { return std::suspend_always{}; }
    auto final_suspend() noexcept { return std::suspend_always{}; }
    void return_void() {}
    task get_return_object() { return task{}; }
    void unhandled_exception() noexcept {}
  };

  ~task() noexcept {}

  bool await_ready() const noexcept { return false; }
  void await_suspend(std::coroutine_handle<>) noexcept {}
  void await_resume() noexcept {}
};

struct Id
{
    std::unique_ptr<int> value;
};

task g(int);

task f() {
    std::unique_ptr<Id> id;
    co_await g(*id->value);
}