diff -r 71dfb835025d -r 4cdc5e946c99 src/HOL/Tools/reification.ML
--- a/src/HOL/Tools/reification.ML	Sat Oct 02 11:56:11 2021 +0200
+++ b/src/HOL/Tools/reification.ML	Sat Oct 02 12:04:14 2021 +0200
@@ -139,7 +139,7 @@
         Abs (_, xT, ta) =>
           let
             val ([raw_xn], ctxt') = Variable.variant_fixes ["x"] ctxt;
-            val (xn, ta) = Syntax_Trans.variant_abs (raw_xn, xT, ta);  (* FIXME !? *)
+            val (xn, ta) = Term.dest_abs (raw_xn, xT, ta);
             val x = Free (xn, xT);
             val cx = Thm.cterm_of ctxt' x;
             val cta = Thm.cterm_of ctxt' ta;