Re: [Boost-bugs] [Boost C++ Libraries] #5432: Deadlock with thread group's join_all and other modifier methods.

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5432: Deadlock with thread group's join_all and other modifier methods.
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-04-06 14:17:56

#5432: Deadlock with thread group's join_all and other modifier methods.
-------------------------------+--------------------------------------------
  Reporter:  JDKunk@…          |       Owner:  anthonyw   
      Type:  Bugs              |      Status:  new        
 Milestone:  To Be Determined  |   Component:  threads    
   Version:  Boost 1.47.0      |    Severity:  Showstopper
Resolution:                    |    Keywords:             
-------------------------------+--------------------------------------------

Comment (by Jeff Kunkel <JDKunk@…>):

 Woops, I made a mistake on my test case. I never unlocked the mutex in
 run, and I never returned from main.
 {{{
 #include <boost/thread.hpp>

 boost::mutex lock;
 boost::thread * t[128];
 boost::thread_group tg;

 void run(int i) {
   lock.lock();
   // remove_thread locks the thread_group's mutex,
   // and join_all locks the thread_group's mutex
   // causing deadlock.
   tg.remove_thread(t[i]); // ***** Deadlock when tg.m is locked.
   lock.unlock();
 }

 int main() {
   lock.lock();
   for( int i = 0; i < 128; ++i ) {
     t[i] = new boost::thread(run,i);
     tg.add_thread(t[i]);
   }
   lock.unlock();
   tg.join_all(); // ***** Deadlock when tg.m is locked.
   return 0;
 }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5432#comment:1>
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