Make built-in methods picklable through the reduce protocol.

1 files changed, 21 insertions, 1 deletions

diff --git a/Objects/methodobject.c b/Objects/methodobject.c
index ca21a68..55a7d6a 100644
--- a/Objects/methodobject.c
+++ b/Objects/methodobject.c
@@ -159,6 +159,26 @@ meth_dealloc(PyCFunctionObject *m)
     }
 }
 
+static PyObject *
+meth_reduce(PyCFunctionObject *m)
+{
+    PyObject *builtins;
+    PyObject *getattr;
+    _Py_IDENTIFIER(getattr);
+
+    if (m->m_self == NULL || PyModule_Check(m->m_self))
+        return PyUnicode_FromString(m->m_ml->ml_name);
+
+    builtins = PyEval_GetBuiltins();
+    getattr = _PyDict_GetItemId(builtins, &PyId_getattr);
+    return Py_BuildValue("O(Os)", getattr, m->m_self, m->m_ml->ml_name);
+}
+
+static PyMethodDef meth_methods[] = {
+    {"__reduce__", (PyCFunction)meth_reduce, METH_NOARGS, NULL},
+    {NULL, NULL}
+};
+
 /*
  * finds the docstring's introspection signature.
  * if present, returns a pointer pointing to the first '('.
@@ -394,7 +414,7 @@ PyTypeObject PyCFunction_Type = {
     0,                                          /* tp_weaklistoffset */
     0,                                          /* tp_iter */
     0,                                          /* tp_iternext */
-    0,                                          /* tp_methods */
+    meth_methods,                               /* tp_methods */
     meth_members,                               /* tp_members */
     meth_getsets,                               /* tp_getset */
     0,                                          /* tp_base */