From: Raymond Hettinger <python@rcn.com>
Date: Tue, 12 May 2015 02:58:56 +0000 (-0700)
Subject: Defend against a mutation during comparison
X-Git-Tag: v3.5.0b1~202^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b9db9e152f3325b075e59ef4fdecfd0b9ec4746c;p=thirdparty%2FPython%2Fcpython.git

Defend against a mutation during comparison
---

diff --git a/Modules/_heapqmodule.c b/Modules/_heapqmodule.c
index 38bcdbe72cf1..04845f165aa4 100644
--- a/Modules/_heapqmodule.c
+++ b/Modules/_heapqmodule.c
@@ -224,6 +224,11 @@ heappushpop(PyObject *self, PyObject *args)
         return item;
     }
 
+    if (PyList_GET_SIZE(heap) == 0) {
+        PyErr_SetString(PyExc_IndexError, "index out of range");
+        return NULL;
+    }
+
     returnitem = PyList_GET_ITEM(heap, 0);
     Py_INCREF(item);
     PyList_SET_ITEM(heap, 0, item);