[Boost-bugs] [Boost C++ Libraries] #10964: future<future<T>>::unwrap().then() Deadlocks

Subject: [Boost-bugs] [Boost C++ Libraries] #10964: future<future<T>>::unwrap().then() Deadlocks
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-01-23 22:35:36

#10964: future<future<T>>::unwrap().then() Deadlocks
------------------------------+----------------------
 Reporter:  code@…            |      Owner:  anthonyw
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  thread
  Version:  Boost 1.57.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+----------------------
 The shared_state returned by unwrap() doesn't appear to propagate
 continuation information properly. The following code will deadlock, but
 the continuations should be immediately invoked.

 {{{
 struct TestCallback
 {
     typedef boost::future<void> result_type;

     result_type operator()(boost::future<void> future) const
     {
         future.get();
         return boost::make_ready_future();
     }

     result_type operator()(boost::future<boost::future<void>> future)
 const
     {
        future.get();
        return boost::make_ready_future();
     }
 };

 int main()
 {
     boost::make_ready_future().then(
         TestCallback()).unwrap().then(TestCallback()).get();
     return 0;
 }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10964>
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