diff -r 77a5f21c449b -r 93fa1efc7219 src/HOL/Mirabelle/lib/scripts/mirabelle.pl
--- a/src/HOL/Mirabelle/lib/scripts/mirabelle.pl	Thu Mar 03 22:24:58 2016 +0100
+++ b/src/HOL/Mirabelle/lib/scripts/mirabelle.pl	Thu Mar 03 23:33:22 2016 +0100
@@ -159,7 +159,7 @@
 
 my $cmd =
   "\"$ENV{'ISABELLE_PROCESS'}\" " .
-  "-o quick_and_dirty -e 'Multithreading.max_threads_setmp 1 use_thy \"$path/$new_thy_name\" handle _ => exit 1;' -q $mirabelle_logic" .
+  "-o quick_and_dirty -e 'Multithreading.max_threads_setmp 1 use_thy \"$path/$new_thy_name\"' -q $mirabelle_logic" .
   $quiet;
 my $result = system "bash", "-c", $cmd;