From 3cdc2c6de226fa8a1c04cb00294809548ce065ba Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Fri, 18 Oct 2002 13:42:21 +0000
Subject: [PATCH] Backport of 2.183: Fix memory leak in add_subclass() found by
 NealN with valgrind.

---
 Objects/typeobject.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 8a1adc914594..2427c4e24ab7 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -2249,8 +2249,11 @@ add_subclass(PyTypeObject *base, PyTypeObject *type)
 	while (--i >= 0) {
 		ref = PyList_GET_ITEM(list, i);
 		assert(PyWeakref_CheckRef(ref));
-		if (PyWeakref_GET_OBJECT(ref) == Py_None)
-			return PyList_SetItem(list, i, new);
+		if (PyWeakref_GET_OBJECT(ref) == Py_None) {
+			i = PyList_SetItem(list, i, new);
+			Py_DECREF(new);
+			return i;
+		}
 	}
 	i = PyList_Append(list, new);
 	Py_DECREF(new);
-- 
2.47.3