From 9ee4b94f51d19a37db3b93222b5e15c8379db78d Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Fri, 24 May 2002 18:47:47 +0000
Subject: [PATCH] Add a safeguard against setting the class to something with a
 different free or alloc slot.

---
 Objects/typeobject.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 9a20fa4e049..61cbeae3777 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -1622,6 +1622,16 @@ object_set_class(PyObject *self, PyObject *value, void *closure)
 		return -1;
 	}
 	new = (PyTypeObject *)value;
+	if (new->tp_dealloc != old->tp_dealloc ||
+	    new->tp_free != old->tp_free)
+	{
+		PyErr_Format(PyExc_TypeError,
+			     "__class__ assignment: "
+			     "'%s' deallocator differs from '%s'",
+			     new->tp_name,
+			     old->tp_name);
+		return -1;
+	}
 	newbase = new;
 	oldbase = old;
 	while (equiv_structs(newbase, newbase->tp_base))