线程池卡在等待条件

Question

我使用此线程池类遇到卡在我的c ++程序中：

class ThreadPool {

    unsigned threadCount;
    std::vector<std::thread> threads;
    std::list<std::function<void(void)> > queue;

    std::atomic_int jobs_left;
    std::atomic_bool bailout;
    std::atomic_bool finished;
    std::condition_variable job_available_var;
    std::condition_variable wait_var;
    std::mutex wait_mutex;
    std::mutex queue_mutex;
    std::mutex mtx;

    void Task() {
        while (!bailout) {
            next_job()();
            --jobs_left;
            wait_var.notify_one();
       }
    }

    std::function<void(void)> next_job() {
        std::function<void(void)> res;
        std::unique_lock<std::mutex> job_lock(queue_mutex);

        // Wait for a job if we don't have any.
        job_available_var.wait(job_lock, [this]()->bool { return queue.size() || bailout; });

        // Get job from the queue
        mtx.lock();
        if (!bailout) {
            res = queue.front();
            queue.pop_front();
        }else {
            // If we're bailing out, 'inject' a job into the queue to keep jobs_left accurate.
            res = [] {};
            ++jobs_left;
        }
        mtx.unlock();
        return res;
    }

public:
    ThreadPool(int c)
        : threadCount(c)
        , threads(threadCount)
        , jobs_left(0)
        , bailout(false)
        , finished(false)
    {
        for (unsigned i = 0; i < threadCount; ++i)
            threads[i] = std::move(std::thread([this, i] { this->Task(); }));
    }

    ~ThreadPool() {
        JoinAll();
    } 

    void AddJob(std::function<void(void)> job) {
        std::lock_guard<std::mutex> lock(queue_mutex);
        queue.emplace_back(job);
        ++jobs_left;
        job_available_var.notify_one();
    }

    void JoinAll(bool WaitForAll = true) {
        if (!finished) {
            if (WaitForAll) {
                WaitAll();
            }

            // note that we're done, and wake up any thread that's
            // waiting for a new job
            bailout = true;
            job_available_var.notify_all();

            for (auto& x : threads)
                if (x.joinable())
                    x.join();
            finished = true;
        }
    }

    void WaitAll() {
        std::unique_lock<std::mutex> lk(wait_mutex);
        if (jobs_left > 0) {
            wait_var.wait(lk, [this] { return this->jobs_left == 0; });
        }
        lk.unlock();
    }
};

gdb说（当停止被阻止的执行时）卡住了（std :: unique_lock＆amp;，ThreadPool :: WaitAll（）:: {lambda（）＃1}）+ 58＆gt;

我使用支持c ++ 14的g ++ v5.3.0（-std = c ++ 1y）

我该如何避免这个问题？

更新

我已编辑（重写）课程：https://github.com/edoz90/threadpool/blob/master/ThreadPool.h