diff --git a/Modules/_heapqmodule.c b/Modules/_heapqmodule.c index 38bcdbe72cf..04845f165aa 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);