std::async - не вызывается деструктор

#include <iostream>
#include <random>
#include <future>

#define USE_STD_ASYNC 1

class Context final {
public:
    int value;

    static Context &threadLocal()
    {
        thread_local static Context context;
        return context;
    }

private:

    Context()
    {
        std::random_device rd;
        std::mt19937 mt(rd());
        std::uniform_int_distribution<> dist(1, 100);

        value = dist(mt);

        std::cout << __FUNCTION__ << "; random value: " << value << "; thread id: " << std::this_thread::get_id() << std::endl;
    }

    ~Context()
    {
        std::cout << __FUNCTION__ << "; random value: " << value << "; thread id: " << std::this_thread::get_id() << std::endl;
    }
};

auto ContextDependedProcedure()
{
    return Context::threadLocal().value;
}

void main()
{
#if USE_STD_ASYNC
    auto future = std::async(std::launch::async, ContextDependedProcedure);
#else
    std::packaged_task<decltype(ContextDependedProcedure)> task(ContextDependedProcedure);

    auto future = task.get_future();

    std::thread thread(std::move(task));
    thread.detach();
#endif

    std::this_thread::yield();

    std::cout << "Second thread value: " << future.get() << std::endl;
}