News for the tp_flags change.
diff --git a/Misc/NEWS b/Misc/NEWS
index ca30ad5..05ceab6 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,14 @@
Core and Builtins
-----------------
+- Issue #1878: Remove Py_TPFLAGS_HAVE_VERSION_TAG from
+ Py_TPFLAGS_DEFAULT when not building the core. This means 3rd party
+ extensions do not automatically benefit from the class attribute
+ cache; they will have to explicitly add Py_TPFLAGS_HAVE_VERSION_TAG
+ to their tp_flags field if they care. This is a backwards
+ compatibility feature; in 3.0, all types will use the cache by
+ default.
+
- Keyword arguments can now follow starred arguments. (``f(a, *args,
keyword=23)`` is now valid syntax.)