commit 4cde4bdcc86cb08ee3847500a172cc24eba37ffe
author INADA Naoki <methane@users.noreply.github.com> Mon Sep 04 12:31:41 2017 +0900
committer GitHub <noreply@github.com> Mon Sep 04 12:31:41 2017 +0900
tree cfc4c00f39f0cc6e9fec1e9756cf81c059ff9d6a
parent 990b2d043cdfaafc3378550f7d27259410a6b918

bpo-31095: Fix potential crash during GC (GH-3197)

(cherry picked from commit a6296d34a478b4f697ea9db798146195075d496c)

Modules/_collectionsmodule.c

diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
index 1dd4b99..2e4da4c 100644
--- a/Modules/_collectionsmodule.c
+++ b/Modules/_collectionsmodule.c
@@ -1271,6 +1271,8 @@
 static void
 dequeiter_dealloc(dequeiterobject *dio)
 {
+    /* bpo-31095: UnTrack is needed before calling any callbacks */
+    PyObject_GC_UnTrack(dio);
     Py_XDECREF(dio->deque);
     PyObject_GC_Del(dio);
 }
@@ -1556,6 +1558,8 @@
 static void
 defdict_dealloc(defdictobject *dd)
 {
+    /* bpo-31095: UnTrack is needed before calling any callbacks */
+    PyObject_GC_UnTrack(dd);
     Py_CLEAR(dd->default_factory);
     PyDict_Type.tp_dealloc((PyObject *)dd);
 }