Defend against a mutation during comparison

b9db9e15 · Raymond Hettinger · 1af2bf75 · b9db9e15
Commit b9db9e15 authored May 11, 2015 by Raymond Hettinger
Hide whitespace changes
Inline Side-by-side

Showing with 5 additions and 0 deletions

Modules/_heapqmodule.c Modules/_heapqmodule.c +5 -0

No files found.
--- 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);