diff -r 890f2f9b926d -r 41aa67a045f7 src/Pure/Isar/toplevel.ML
--- a/src/Pure/Isar/toplevel.ML	Wed Nov 18 11:03:49 1998 +0100
+++ b/src/Pure/Isar/toplevel.ML	Wed Nov 18 11:12:29 1998 +0100
@@ -233,6 +233,7 @@
 
 fun exn_message TERMINATE = "Exit."
   | exn_message (BREAK _) = "Break."
+  | exn_message (FAIL (exn, msg)) = cat_lines [exn_message exn, msg]
   | exn_message Interrupt = "Interrupt (exec)."
   | exn_message (ERROR_MESSAGE msg) = msg
   | exn_message (THEORY (msg, _)) = msg