[Boost-bugs] [Boost C++ Libraries] #4089: Memory leak in Boost.Signals2 when the signal is not invoked

Subject: [Boost-bugs] [Boost C++ Libraries] #4089: Memory leak in Boost.Signals2 when the signal is not invoked
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-04-12 16:56:11

#4089: Memory leak in Boost.Signals2 when the signal is not invoked
------------------------------------+---------------------------------------
 Reporter:  dan.berindei@…          |       Owner:  fmhess  
     Type:  Bugs                    |      Status:  new     
Milestone:  Boost 1.43.0            |   Component:  signals2
  Version:  Boost 1.42.0            |    Severity:  Problem 
 Keywords:                          |  
------------------------------------+---------------------------------------
 The attached program leaks memory by attaching and detaching slots from a
 signal in a loop:
 {{{
 boost::signals2::signal<void(void)> sig;
 boost::signals2::connection conn1, conn2, conn3, conn4;

 while (true) {
     conn1.disconnect();
     conn2.disconnect();

     conn1 = sig.connect(slot);
     conn2 = sig.connect(slot);

     conn3.disconnect();
     conn4.disconnect();

     conn3 = sig.connect(slot);
     conn4 = sig.connect(slot);

     //sig();
 }
 }}}
 Invoking the signal (i.e. uncommenting the 'sig()' line) plugs the memory
 leak, however in my original setting it entails lots of unnecessary work
 so it's not a very good solution.

 My guess is that _garbage_collector_it is set to
 _shared_state->connection_bodies().end() on invocation, but not on a new
 connection, so it never goes back to the beginning of the list.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4089>
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