diff options
Diffstat (limited to 'src/threadpool.h')
| -rw-r--r-- | src/threadpool.h | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/src/threadpool.h b/src/threadpool.h index 5b3f823..42c36ed 100644 --- a/src/threadpool.h +++ b/src/threadpool.h @@ -29,6 +29,13 @@ /// Class managing a pool of worker threads. /// Work can be queued by passing a function to queue(). When the /// work is done the result of the function will be passed back via a future. +/// +/// Note that due to a bug in Visual Studio's std::packaged_task implementation +/// it does not allow m_work to have a void() template parameter, and still assign +/// R() to it (you will get C2280: "attempting to reference a deleted function error"). +/// So to work around this we pass the return type with the class itself :-( +/// See also https://stackoverflow.com/q/26733430/784672 +template<class R> class ThreadPool { public: @@ -54,7 +61,9 @@ class ThreadPool /// Queue the lambda 'task' for the threads to execute. /// A future of the return type of the lambda is returned to capture the result. - template<class F, class R=std::result_of_t<F&()> > + /// use this once the Visual Studio bug is fixed: + /// template<class F, class R=std::result_of_t<F&()> > + template<class F> std::future<R> queue(F&& f) { // wrap the function object into a packaged task, splitting @@ -98,7 +107,7 @@ class ThreadPool while(true) { // pop a task off the queue: - std::packaged_task<void()> f; + std::packaged_task<R()> f; { // usual thread-safe queue code: std::unique_lock<std::mutex> l(m_mutex); @@ -121,8 +130,8 @@ class ThreadPool std::mutex m_mutex; std::condition_variable m_cond; - // note that a packaged_task<void> can store a packaged_task<R>: - std::deque< std::packaged_task<void()> > m_work; + // note that a packaged_task<void()> can store a packaged_task<R()> (but not with buggy Visual Studio) + std::deque< std::packaged_task<R()> > m_work; // this holds futures representing the worker threads being done: std::vector< std::future<void> > m_finished; |