调用带有std :: async的unique_ptr的函数

Question

我试图让std::async启动一个接受unique_ptr gcc 4.6.2的函数：

#include <type_traits>
#include <memory>
#include <functional>
#include <future>

struct Foo {};

// my gcc does not have this, same definition as in 30.2.6
template<typename T>
typename std::decay<T>::type decay_copy(T&& v) { return std::forward<T>(v); }

int main() {
  std::function<int(std::unique_ptr<Foo>)> f = [](std::unique_ptr<Foo>) { return 23; };

  std::unique_ptr<Foo> fp{new Foo};
  std::unique_ptr<Foo> fp2{std::move(fp)};
  // works, this seems to satisfy the requirements of async
  f(decay_copy(std::move(fp2)));

  // does not work with reference to a deleted function
  // std::async(f, std::move(fp2));
}

这是预期的行为还是gcc错误？

Answer 1

可能是一个错误。它可以用g ++ 4.7编译。