src/HOL/MicroJava/JVM/JVMDefensive.thy

--- a/src/HOL/MicroJava/JVM/JVMDefensive.thy	Tue Sep 09 17:51:07 2014 +0200
+++ b/src/HOL/MicroJava/JVM/JVMDefensive.thy	Tue Sep 09 20:51:36 2014 +0200
@@ -11,7 +11,7 @@
 text {*
   Extend the state space by one element indicating a type error (or
   other abnormal termination) *}
-datatype 'a type_error = TypeError | Normal 'a
+datatype_new 'a type_error = TypeError | Normal 'a
 
 
 abbreviation