src/Pure/Tools/build_dialog.scala

--- a/src/Pure/Tools/build_dialog.scala	Sat Sep 07 17:11:44 2013 +0200
+++ b/src/Pure/Tools/build_dialog.scala	Sat Sep 07 17:23:05 2013 +0200
@@ -36,7 +36,7 @@
 
             val system_dialog = new System_Dialog
             dialog(options, system_dialog, system_mode, dirs, session)
-            sys.exit(system_dialog.join)
+            system_dialog.join_exit
 
         case _ => error("Bad arguments:\n" + cat_lines(args))
       }