diff -r 5c8177fd1295 -r 8e6c973003c8 src/Pure/simplifier.ML
--- a/src/Pure/simplifier.ML	Wed Oct 20 17:11:46 2021 +0200
+++ b/src/Pure/simplifier.ML	Wed Oct 20 18:13:17 2021 +0200
@@ -101,7 +101,6 @@
 (
   type T = simproc Name_Space.table;
   val empty : T = Name_Space.empty_table "simproc";
-  val extend = I;
   fun merge data : T = Name_Space.merge_tables data;
 );