bpo-33199: Initialize ma_version_tag in PyDict_Copy (GH-6341)

miss-islington · methane · web-flow · commit 9a90826c9b64 · 2018-04-02T20:22:14.000-07:00
(cherry picked from commit d1c82c5) Co-authored-by: INADA Naoki <methane@users.noreply.github.com>
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
@@ -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
@@ -2654,6 +2654,7 @@ 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];

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+Fix ``ma_version_tag`` in dict implementation is uninitialized when copying
	`2`	`+from key-sharing dict.`