Issue #8268: Old-style classes (not just instances) now support weak
references.
diff --git a/Objects/classobject.c b/Objects/classobject.c
index 3f51c0f..032d354 100644
--- a/Objects/classobject.c
+++ b/Objects/classobject.c
@@ -123,6 +123,7 @@
op->cl_dict = dict;
Py_XINCREF(name);
op->cl_name = name;
+ op->cl_weakreflist = NULL;
op->cl_getattr = class_lookup(op, getattrstr, &dummy);
op->cl_setattr = class_lookup(op, setattrstr, &dummy);
@@ -188,6 +189,8 @@
class_dealloc(PyClassObject *op)
{
_PyObject_GC_UNTRACK(op);
+ if (op->cl_weakreflist != NULL)
+ PyObject_ClearWeakRefs((PyObject *) op);
Py_DECREF(op->cl_bases);
Py_DECREF(op->cl_dict);
Py_XDECREF(op->cl_name);
@@ -454,7 +457,7 @@
(traverseproc)class_traverse, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
- 0, /* tp_weaklistoffset */
+ offsetof(PyClassObject, cl_weakreflist), /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
0, /* tp_methods */