Re: [Boost-users] [boost][thread] Future returning 0xfeeefeee
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Zitat von Klaim - Joël Lamotte
My current suspicion: maybe I do something wrong with the lifetime of the promise? I don't see what unfortunately.
your example is not easy to read. IIUC, after execute(), the work queue is emptied and the last shared_ptr to struct K goes out of scope. K contains your promise and the future associated with it is accessed after the promise has been destroyed. try a breakpoint in the destructor of K to make sure, I don't have tbb installed to test.
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On Sun, Apr 7, 2013 at 12:47 AM, Stefan Strasser
your example is not easy to read. IIUC, after execute(), the work queue is emptied and the last shared_ptr to struct K goes out of scope. K contains your promise and the future associated with it is accessed after the promise has been destroyed. try a breakpoint in the destructor of K to make sure, I don't have tbb installed to test.
In my last message I provided a simplified version without K. I just make a shared_ptr of the promise. As the use of the shared_ptr is inside the lambda and I push it in the queue, and I captured it by copy, I know the promise is alive until both the lambda and the do_some_work() function are both executed fully. So the promise is destroyed before setting the value to the future. In doubt, I also tested by making the future before pushing the lambda. But it's the same thing going on in sequential code like the one I provide in the test. When debugging, I can see that the future is set when the promise.set_value() is called. However, it seem that the return of future.get() is wrong, but when I go step by step inside the get() implementation, I don't see where the value is lost. Could it be that the "reset" of boost::future corrupt the returned type? I'm currently looking for other clues. Joel Lamotte
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On Sun, Apr 7, 2013 at 1:02 AM, Klaim - Joël Lamotte
So the promise is destroyed before setting the value to the future.
Sorry, I meant: the promise is (a priori) guaranteed to be destroyed AFTER having set the value to the future. Joel Lamotte
participants (2)
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Klaim - Joël Lamotte
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Stefan Strasser