[Boost-bugs] [Boost C++ Libraries] #11220: future<>::wait_for() on continuation doesn't return after timeout.

Subject: [Boost-bugs] [Boost C++ Libraries] #11220: future<>::wait_for() on continuation doesn't return after timeout.
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-04-21 15:53:44

#11220: future<>::wait_for() on continuation doesn't return after timeout.
-------------------------------------------+----------------------
 Reporter:  Konrad Zemek <konrad.zemek@…>  |      Owner:  anthonyw
     Type:  Bugs                           |     Status:  new
Milestone:  To Be Determined               |  Component:  thread
  Version:  Boost 1.58.0                   |   Severity:  Problem
 Keywords:  wait_for future continuation   |
-------------------------------------------+----------------------
 If the original future's value will never be set, the wait_for() on
 continuation will deadlock.

 I'm using Boost 1.58 with Thread patched to commit
 0bed674233a3c94b7254037dc4903961b54eb141 .

 Example to reproduce:
 {{{#!c++
 #define BOOST_THREAD_VERSION 4
 #define BOOST_THREAD_PROVIDES_EXECUTORS

 #include <boost/thread.hpp>
 #include <boost/thread/executor.hpp>
 #include <boost/thread/thread_pool.hpp>

 #include <future>
 #include <chrono>

 void wait_for() {
       boost::promise<void> promise;
       auto future = promise.get_future();
       future.wait_for(boost::chrono::milliseconds(100));
 }

 void wait_for_executor() {
       boost::promise<void> promise;
       auto future = promise.get_future();
       auto far_future = future.then(boost::launch::async, [](auto){});
       far_future.wait_for(boost::chrono::milliseconds(100));
 }

 int main() {
       // works
       wait_for();

       // deadlocks
       wait_for_executor();
 }
 }}}


 GDB backtrace:
 {{{
 Thread 1 (Thread 0x7ffff7fe6780 (LWP 247)):
 #0  pthread_cond_wait@@GLIBC_2.3.2 ()
     at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
 #1  0x000000000040df1e in boost::condition_variable::wait (this=0x63f3e8,
 m=...)
     at /usr/include/boost/thread/pthread/condition_variable.hpp:73
 #2  0x00000000004105a1 in boost::detail::shared_state_base::wait_internal
 (this=0x63f380,
     lk=..., rethrow=false) at /usr/include/boost/thread/future.hpp:305
 #3  0x000000000041061a in boost::detail::shared_state_base::wait
 (this=0x63f380, lock=...,
     rethrow=false) at /usr/include/boost/thread/future.hpp:315
 #4  0x0000000000422c1f in
 boost::detail::future_async_shared_state_base<void>::wait (
     this=0x63f380, lk=..., rethrow=false) at
 /usr/include/boost/thread/future.hpp:771
 #5  0x0000000000422bb6 in
 boost::detail::future_async_shared_state_base<void>::block_if_needed
     (this=0x63f380, lk=...) at /usr/include/boost/thread/future.hpp:757
 #6  0x000000000040fed6 in boost::detail::shared_state_base::dec
 (this=0x63f380, lk=...)
     at /usr/include/boost/thread/future.hpp:181
 #7  0x000000000040ff1e in boost::detail::shared_state_base::dec
 (this=0x63f380)
     at /usr/include/boost/thread/future.hpp:184
 #8  0x000000000041a2b6 in boost::detail::basic_future<void>::~basic_future
 (
     this=0x7fffffffeb80, __in_chrg=<optimized out>)
     at /usr/include/boost/thread/future.hpp:1188
 #9  0x00000000004147ca in boost::future<void>::~future
 (this=0x7fffffffeb80,
     __in_chrg=<optimized out>) at
 /usr/include/boost/thread/future.hpp:1541
 #10 0x000000000040a920 in wait_for_executor () at wait_for_example.cpp:20
 #11 0x000000000040a99f in main () at wait_for_example.cpp:29
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11220>
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