diff --git a/Misc/NEWS.d/next/Library/2026-07-03-14-54-33.gh-issue-152951.u8tPCI.rst b/Misc/NEWS.d/next/Library/2026-07-03-14-54-33.gh-issue-152951.u8tPCI.rst new file mode 100644 index 00000000000000..c3d56c6d59c91b --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-07-03-14-54-33.gh-issue-152951.u8tPCI.rst @@ -0,0 +1,2 @@ +:class:`collections.deque` prevent rare crash when calling ``extend`` under +high memory pressure conditions. diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c index eed976bad79283..e48fe39dda6a09 100644 --- a/Modules/_collectionsmodule.c +++ b/Modules/_collectionsmodule.c @@ -508,7 +508,6 @@ deque_extend_impl(dequeobject *deque, PyObject *iterable) iternext = *Py_TYPE(it)->tp_iternext; while ((item = iternext(it)) != NULL) { if (deque_append_lock_held(deque, item, maxlen) == -1) { - Py_DECREF(item); Py_DECREF(it); return NULL; }