From d1c82c5cc7be0c21dddf86fd19c1702f6218459b Mon Sep 17 00:00:00 2001
From: INADA Naoki <methane@users.noreply.github.com>
Date: Tue, 3 Apr 2018 11:43:53 +0900
Subject: [PATCH] bpo-33199: Initialize ma_version_tag in PyDict_Copy (GH-6341)
---
.../Core and Builtins/2018-04-02-09-32-40.bpo-33199.TPnxQu.rst | 2 ++
Objects/dictobject.c | 1 +
2 files changed, 3 insertions(+)
create mode 100644 Misc/NEWS.d/next/Core and Builtins/2018-04-02-09-32-40.bpo-33199.TPnxQu.rst
diff --git a/Misc/NEWS.d/next/Core and Builtins/2018-04-02-09-32-40.bpo-33199.TPnxQu.rst b/Misc/NEWS.d/next/Core and Builtins/2018-04-02-09-32-40.bpo-33199.TPnxQu.rst
new file mode 100644
index 0000000000..22abf8d000
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2018-04-02-09-32-40.bpo-33199.TPnxQu.rst
@@ -0,0 +1,2 @@
+Fix ``ma_version_tag`` in dict implementation is uninitialized when copying
+from key-sharing dict.
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index bb4ea1f5f9..be895d4c15 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -2551,6 +2551,7 @@ PyDict_Copy(PyObject *o)
split_copy->ma_values = newvalues;
split_copy->ma_keys = mp->ma_keys;
split_copy->ma_used = mp->ma_used;
+ split_copy->ma_version_tag = DICT_NEXT_VERSION();
DK_INCREF(mp->ma_keys);
for (i = 0, n = size; i < n; i++) {
PyObject *value = mp->ma_values[i];
--
2.40.0