id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
11275,Deadlock when destroying continuation future,Konrad Zemek <konrad.zemek@…>,viboes,"I've stumbled upon a deadlock somewhere in continuation logic. I think the trace below will show it clearly. Basically, the future's destructor waits on lock that was already locked earlier in the callstack:

In the continuation sequence:
{{{
#22 0x0000000000505283 in boost::detail::shared_state_base::do_continuation (this=0x18979d0, lock=...)
    at /usr/include/boost/thread/future.hpp:239
239	                  }
(gdb) print lock
$2 = (boost::unique_lock<boost::mutex> &) @0x7f6e62783520: {m = 0x1897a10, is_locked = true}
}}}

Later during destruction:
{{{
#7  0x0000000000505083 in boost::detail::shared_state_base::dec (this=0x18979d0) at /usr/include/boost/thread/future.hpp:197
197	            void dec() { boost::unique_lock<boost::mutex> lk(this->mutex); dec(lk); }
(gdb) print lk
$4 = {m = 0x1897a10, is_locked = false}
}}}

Following is the trace from GDB. I attach my version of future.hpp for line number reference. It's the version from 71d9a0a merged with boost-1.58 tag.

{{{
Thread 2 (Thread 0x7f6e62786700 (LWP 12760)):
#0  __lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
#1  0x00007f6e64b8156a in _L_lock_913 () from /lib/x86_64-linux-gnu/libpthread.so.0
#2  0x00007f6e64b81390 in __GI___pthread_mutex_lock (mutex=0x1897a10) at ../nptl/pthread_mutex_lock.c:79
#3  0x000000000050236a in pthread_mutex_lock (m=0x1897a10) at /usr/include/boost/thread/pthread/mutex.hpp:62
#4  boost::mutex::lock (this=0x1897a10) at /usr/include/boost/thread/pthread/mutex.hpp:116
#5  0x000000000050f881 in boost::unique_lock<boost::mutex>::lock (this=0x7f6e627831f0)
    at /usr/include/boost/thread/lock_types.hpp:346
#6  0x000000000050f9e9 in boost::unique_lock<boost::mutex>::unique_lock (this=0x7f6e627831f0, m_=...)
    at /usr/include/boost/thread/lock_types.hpp:124
#7  0x0000000000505083 in boost::detail::shared_state_base::dec (this=0x18979d0) at /usr/include/boost/thread/future.hpp:197
#8  0x000000000052850e in boost::detail::basic_future<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >::~basic_future (this=0x1897c58, __in_chrg=<optimized out>)
    at /usr/include/boost/thread/future.hpp:1212
#9  0x000000000051f46e in boost::future<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >::~future (this=0x1897c58, __in_chrg=<optimized out>) at /usr/include/boost/thread/future.hpp:1822
#10 0x0000000000534fbc in boost::detail::future_unwrap_shared_state<boost::future<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >, std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > >::~future_unwrap_shared_state (this=0x1897b40, __in_chrg=<optimized out>)
    at /usr/include/boost/thread/future.hpp:5043
#11 0x0000000000534ff8 in boost::detail::future_unwrap_shared_state<boost::future<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >, std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > >::~future_unwrap_shared_state (this=0x1897b40, __in_chrg=<optimized out>)
    at /usr/include/boost/thread/future.hpp:5043
#12 0x0000000000535030 in boost::checked_delete<boost::detail::future_unwrap_shared_state<boost::future<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >, std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > > (x=0x1897b40)
    at /usr/include/boost/core/checked_delete.hpp:34
#13 0x00000000005382ee in boost::detail::sp_counted_impl_p<boost::detail::future_unwrap_shared_state<boost::future<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >, std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >::dispose (this=0x1897880)
    at /usr/include/boost/smart_ptr/detail/sp_counted_impl.hpp:78
#14 0x00000000005017e2 in boost::detail::sp_counted_base::release (this=0x1897880)
    at /usr/include/boost/smart_ptr/detail/sp_counted_base_gcc_x86.hpp:146
#15 0x00000000005018a5 in boost::detail::shared_count::~shared_count (this=0x7f6e5c0008c8, __in_chrg=<optimized out>)
    at /usr/include/boost/smart_ptr/detail/shared_count.hpp:443
#16 0x0000000000505114 in boost::shared_ptr<boost::detail::shared_state_base>::~shared_ptr (this=0x7f6e5c0008c0, 
    __in_chrg=<optimized out>) at /usr/include/boost/smart_ptr/shared_ptr.hpp:323
#17 0x000000000052f13e in std::_Destroy<boost::shared_ptr<boost::detail::shared_state_base> > (__pointer=0x7f6e5c0008c0)
    at /usr/include/c++/4.9/bits/stl_construct.h:93
#18 0x0000000000529d5d in std::_Destroy_aux<false>::__destroy<boost::shared_ptr<boost::detail::shared_state_base>*> (
    __first=0x7f6e5c0008c0, __last=0x7f6e5c0008d0) at /usr/include/c++/4.9/bits/stl_construct.h:103
#19 0x00000000005228f3 in std::_Destroy<boost::shared_ptr<boost::detail::shared_state_base>*> (__first=0x7f6e5c0008c0, 
    __last=0x7f6e5c0008d0) at /usr/include/c++/4.9/bits/stl_construct.h:126
#20 0x0000000000516107 in std::_Destroy<boost::shared_ptr<boost::detail::shared_state_base>*, boost::shared_ptr<boost::detail::shared_state_base> > (__first=0x7f6e5c0008c0, __last=0x7f6e5c0008d0) at /usr/include/c++/4.9/bits/stl_construct.h:151
#21 0x000000000050d24f in std::vector<boost::shared_ptr<boost::detail::shared_state_base>, std::allocator<boost::shared_ptr<boost::detail::shared_state_base> > >::~vector (this=0x7f6e62783450, __in_chrg=<optimized out>)
    at /usr/include/c++/4.9/bits/stl_vector.h:424
#22 0x0000000000505283 in boost::detail::shared_state_base::do_continuation (this=0x18979d0, lock=...)
    at /usr/include/boost/thread/future.hpp:239
#23 0x0000000000505412 in boost::detail::shared_state_base::mark_finished_internal (this=0x18979d0, lock=...)
    at /usr/include/boost/thread/future.hpp:265
#24 0x0000000000544a2d in boost::detail::shared_state<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >::mark_finished_with_result_internal(boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > >&&, boost::unique_lock<boost::mutex>&) (this=0x18979d0, 
    result_=<unknown type in /home/kzemek/plgrid/helpers/debug/test/unit/inbox_test, CU 0xa555, DIE 0x4091f>, lock=...)
    at /usr/include/boost/thread/future.hpp:526
#25 0x000000000054499f in boost::detail::shared_state<boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > > >::mark_finished_with_result(boost::future<std::unique_ptr<one::clproto::ServerMessage, std::default_delete<one::clproto::ServerMessage> > >&&) (this=0x18979d0, 
---Type <return> to continue, or q <return> to quit---
    result_=<unknown type in /home/kzemek/plgrid/helpers/debug/test/unit/inbox_test, CU 0xa555, DIE 0x4091f>)
    at /usr/include/boost/thread/future.hpp:554
#26 0x00000000005448be in _ZN5boost6detail41future_executor_continuation_shared_stateINS_9executors17basic_thread_poolENS_6futureIvEENS4_ISt10unique_ptrIN3one7clproto13ServerMessageESt14default_deleteIS9_EEEEZNS7_13communication6layers5InboxI10LowerLayerE11communicateES6_INS8_13ClientMessageESA_ISJ_EEiEUlT_E_E3runENS_10shared_ptrINS0_17shared_state_baseEEE (that_=...)
    at /usr/include/boost/thread/future.hpp:4303
#27 0x0000000000544738 in _ZN5boost6detail6run_itINS0_41future_executor_continuation_shared_stateINS_9executors17basic_thread_poolENS_6futureIvEENS5_ISt10unique_ptrIN3one7clproto13ServerMessageESt14default_deleteISA_EEEEZNS8_13communication6layers5InboxI10LowerLayerE11communicateES7_INS9_13ClientMessageESB_ISK_EEiEUlT_E_EEEclEv (this=0x18978a8)
    at /usr/include/boost/thread/future.hpp:4274
#28 0x00000000005445ba in _ZN5boost6detail16nullary_functionIFvvEE9impl_typeINS0_6run_itINS0_41future_executor_continuation_shared_stateINS_9executors17basic_thread_poolENS_6futureIvEENS9_ISt10unique_ptrIN3one7clproto13ServerMessageESt14default_deleteISE_EEEEZNSC_13communication6layers5InboxI10LowerLayerE11communicateESB_INSD_13ClientMessageESF_ISO_EEiEUlT_E_EEEEE4callEv (
    this=0x18978a0) at /usr/include/boost/thread/detail/nullary_function.hpp:52
#29 0x0000000000507245 in boost::detail::nullary_function<void ()>::operator()() (this=0x7f6e62783690)
    at /usr/include/boost/thread/detail/nullary_function.hpp:125
#30 0x00000000005072a3 in boost::executors::basic_thread_pool::worker_thread (this=0x1894ba0)
    at /usr/include/boost/thread/executors/basic_thread_pool.hpp:91
#31 0x000000000053f129 in boost::detail::invoke<void (boost::executors::basic_thread_pool::*)(), boost::executors::basic_thread_pool<>*>(void (boost::executors::basic_thread_pool::*&&)(), boost::executors::basic_thread_pool<>*&&, (boost::executors::basic_thread_pool<>*&&)...) (
    f=<unknown type in /home/kzemek/plgrid/helpers/debug/test/unit/inbox_test, CU 0xa555, DIE 0xa1b40>, 
    a0=<unknown type in /home/kzemek/plgrid/helpers/debug/test/unit/inbox_test, CU 0xa555, DIE 0xa1b45>)
    at /usr/include/boost/thread/detail/invoke.hpp:77
#32 0x000000000053c705 in boost::detail::thread_data<void (boost::executors::basic_thread_pool::*)(), boost::executors::basic_thread_pool*>::run2<1ul> (this=0x1894f20) at /usr/include/boost/thread/detail/thread.hpp:75
#33 0x0000000000538e5a in boost::detail::thread_data<void (boost::executors::basic_thread_pool::*)(), boost::executors::basic_thread_pool*>::run (this=0x1894f20) at /usr/include/boost/thread/detail/thread.hpp:81
#34 0x00007f6e64da5d8a in ?? () from /usr/lib/x86_64-linux-gnu/libboost_thread.so.1.58.0
#35 0x00007f6e64b7f0a5 in start_thread (arg=0x7f6e62786700) at pthread_create.c:309
#36 0x00007f6e63e1ecfd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
}}}",Support Requests,closed,,thread,Boost 1.58.0,Problem,worksforme,continuation deadlock destructor,