diff -r 42aa700354d6 -r 4a396c7a77b5 lib/Tools/codegen
--- a/lib/Tools/codegen	Fri Feb 13 10:30:26 2009 +0100
+++ b/lib/Tools/codegen	Fri Feb 13 10:41:56 2009 +0100
@@ -36,5 +36,5 @@
 THY=$(echo $THY | sed -e 's/\\/\\\\"/g; s/"/\\\"/g')
 ISAR="theory Codegen imports \"$THY\" begin export_code $CMD end"
 
-echo "$ISAR" | "$ISABELLE_TOOL" tty -l "$IMAGE" || exit 1
-
+echo "$ISAR" | "$ISABELLE_TOOL" tty -l "$IMAGE"
+exit ${PIPESTATUS[1]}