[Boost-bugs] [Boost C++ Libraries] #8290: Python GIL not acquired before freeing shared_ptr, causes crash

Subject: [Boost-bugs] [Boost C++ Libraries] #8290: Python GIL not acquired before freeing shared_ptr, causes crash
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-03-13 12:05:02

#8290: Python GIL not acquired before freeing shared_ptr, causes crash
--------------------------------+-------------------------------------------
 Reporter:  team@…              |       Owner:  rwgk   
     Type:  Bugs                |      Status:  new    
Milestone:  To Be Determined    |   Component:  Python 
  Version:  Boost 1.52.0        |    Severity:  Problem
 Keywords:                      |  
--------------------------------+-------------------------------------------
 We're successfully using boost::python with Python on multiple threads
 that lock and release the GIL as appropriate, and correctly set the Python
 thread state, etc.

 One thing we don't have control over, however, is the freeing of
 shared_ptr objects which were created by boost::python.  This may happen
 on a different thread than the previous Python execution and/or without
 the GIL being locked.  To fix this, the following patch is required:

 {{{
 --- builtin_converters.cpp      2011-06-07 06:15:33.000000000 +0200
 +++ builtin_converters.cpp.fixed        2013-03-13 12:57:29.346638173
 +0100
 @@ -32,7 +32,9 @@

  void shared_ptr_deleter::operator()(void const*)
  {
 +    PyGILState_STATE gil = PyGILState_Ensure();
      owner.reset();
 +    PyGILState_Release(gil);
  }

  namespace
 }}}

 This fix can be applied externally to boost::python, but requires a few
 header files that re-implement shared_ptr_to_python.hpp and
 shared_ptr_from_python.hpp.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8290>
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