--- a/NEWS Fri Jun 19 07:53:35 2015 +0200
+++ b/NEWS Fri Jun 19 21:33:03 2015 +0200
@@ -139,6 +139,9 @@
less_eq_multiset_def
INCOMPATIBILITY
+* Theory Library/Old_Recdef: discontinued obsolete 'defer_recdef'
+command. Minor INCOMPATIBILITY, use 'function' instead.
+
New in Isabelle2015 (May 2015)