-- a/sip/cpp/sip_corewxAppTraits.cpp
++ b/sip/cpp/sip_corewxAppTraits.cpp
PyErr_Clear();
Py_BEGIN_ALLOW_THREADS
sipRes = new ::wxString((sipSelfWasArg ? sipCpp-> ::wxAppTraits::GetAssertStackTrace() : sipCpp->GetAssertStackTrace()));
sipRes = new ::wxString("");
Py_END_ALLOW_THREADS
if (PyErr_Occurred())