commit 5863a396035e1b0bd46d201c7511c2b90c4c1c20
author Benjamin Peterson <benjamin@python.org> Fri May 15 12:19:18 2015 -0400
committer Benjamin Peterson <benjamin@python.org> Fri May 15 12:19:18 2015 -0400
tree 3454fd8f893b47e302bcd6354e5cb5add42a8dff
parent f2fa17ce2a4cebad09d9fc9680e22b06fae81764

deque is not varsized, so using Py_SIZE is nonsensical (closes #24162)

Modules/_collectionsmodule.c

diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
index 1924374..5080a5b 100644
--- a/Modules/_collectionsmodule.c
+++ b/Modules/_collectionsmodule.c
@@ -708,7 +708,7 @@
     PyObject *item;
     int rv;
 
-    assert (i >= 0 && i < Py_SIZE(deque));
+    assert (i >= 0 && i < deque->len);
     if (_deque_rotate(deque, -i))
         return -1;
     item = deque_popleft(deque, NULL);