Backport issue #12973 itertools fix from 3.x.
diff --git a/Misc/NEWS b/Misc/NEWS
index b4dd215..c4f0cb0 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -15,9 +15,9 @@
 - Issue #12973: Fix overflow checks that invoked undefined behaviour in
   int.__pow__.  These overflow checks were causing int.__pow__ to produce
   incorrect results with recent versions of Clang, as a result of the
-  compiler optimizing the check away.  Also fix similar overflow check
-  in list_repeat (which caused test_list to fail with recent versions
-  of Clang).
+  compiler optimizing the check away.  Also fix similar overflow checks
+  in list_repeat (listobject.c) and islice_next (itertoolsmodule.c).  These
+  bugs caused test failures with recent versions of Clang.
 
 - Issue #12266: Fix str.capitalize() to correctly uppercase/lowercase
   titlecased and cased non-letter characters.