From 787bdd37a0817d038aff9ea45d06ceb14dccece4 Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Sun, 17 Aug 1997 16:25:45 +0000
Subject: [PATCH] PyTuple_SetItem should require that the tuple's refcnt is
 one!

---
 Objects/tupleobject.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index 0faedb480ae..d6fb6b4d645 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -133,7 +133,7 @@ PyTuple_SetItem(op, i, newitem)
 {
 	register PyObject *olditem;
 	register PyObject **p;
-	if (!PyTuple_Check(op)) {
+	if (!PyTuple_Check(op) || op->ob_refcnt != 1) {
 		Py_XDECREF(newitem);
 		PyErr_BadInternalCall();
 		return -1;