Optimize the Python 3.8 refcount fix a tiny bit

This change uses the fact that our workaround to temporarily remove
the Py_TPFLAGS_METHOD_DESCRIPTOR flag uses the "mro" function
of PyType_Type, which never will change.
Therefore, the static keyword makes sure that this function lookup
happens only once.

Change-Id: I44b74556da1fac2596c81339af30cb66218276e2
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/sources/shiboken2/libshiboken/basewrapper.cpp b/sources/shiboken2/libshiboken/basewrapper.cpp
index 4030fe1c4..dd5dc43e9 100644
--- a/sources/shiboken2/libshiboken/basewrapper.cpp
+++ b/sources/shiboken2/libshiboken/basewrapper.cpp
@@ -506,7 +506,7 @@ PyObject *SbkObjectTypeTpNew(PyTypeObject *metatype, PyObject *args, PyObject *k
     // PYSIDE-939: This is a temporary patch that circumvents the problem
     // with Py_TPFLAGS_METHOD_DESCRIPTOR until this is finally solved.
     PyObject *ob_PyType_Type = reinterpret_cast<PyObject *>(&PyType_Type);
-    PyObject *mro = PyObject_GetAttr(ob_PyType_Type, Shiboken::PyName::mro());
+    static PyObject *mro = PyObject_GetAttr(ob_PyType_Type, Shiboken::PyName::mro());
     auto hold = Py_TYPE(mro)->tp_flags;
     Py_TYPE(mro)->tp_flags &= ~Py_TPFLAGS_METHOD_DESCRIPTOR;
     auto *newType = reinterpret_cast<SbkObjectType *>(type_new(metatype, args, kwds));