Re: [Boost-bugs] [Boost C++ Libraries] #8978: Segfault crash in boost.python with keyword arguments and overloads.

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #8978: Segfault crash in boost.python with keyword arguments and overloads.
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-08-08 18:32:28

#8978: Segfault crash in boost.python with keyword arguments and overloads.
-------------------------------+-------------------------
  Reporter:  amohr@…           |      Owner:  rwgk
      Type:  Bugs              |     Status:  new
 Milestone:  To Be Determined  |  Component:  Python
   Version:  Boost 1.51.0      |   Severity:  Showstopper
Resolution:                    |   Keywords:
-------------------------------+-------------------------

Comment (by amohr@…):

 Oh man, I didn't realize it would format my input.  Here's the repro and
 patch again, hopefully better formatted.


 {{{
 // C++
 #include <boost/python.hpp>

 static void f1(int a0, int a1) { }
 static void f2(int a0, int a1, int a2) { }

 BOOST_PYTHON_MODULE(kwargCrash) {
     boost::python::def("f", f1, (arg("a1")=2));
     boost::python::def("f", f2, (arg("a2")=2));
 }

 # Python
 import kwargCrash
 kwargCrash.f(0, a1=2)


 --- ./libs/python/src/object/function.cpp.orig  2013-07-22
 17:38:54.000000000 -0700
 +++ ./libs/python/src/object/function.cpp       2013-08-07
 10:25:26.963988000 -0700
 @@ -182,6 +182,16 @@
                              // Get the keyword[, value pair]
 corresponding
                              PyObject* kv =
 PyTuple_GET_ITEM(f->m_arg_names.ptr(), arg_pos);

 +                            // If kv is None, this overload does not
 accept a
 +                            // keyword argument in this position, meaning
 that
 +                            // the caller did not supply enough
 positional
 +                            // arguments.  Reject the overload.
 +                            if (kv == Py_None) {
 +                                PyErr_Clear();
 +                                inner_args = handle<>();
 +                                break;
 +                            }
 +
                              // If there were any keyword arguments,
                              // look up the one we need for this
                              // argument position


 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8978#comment:1>
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