src/Pure/mk

--- a/src/Pure/mk	Mon Dec 16 09:59:18 1996 +0100
+++ b/src/Pure/mk	Mon Dec 16 10:00:08 1996 +0100
@@ -30,4 +30,7 @@
 [ -f "ML-Systems/$ML_SYSTEM.ML" ] && COMPAT="ML-Systems/$ML_SYSTEM.ML"
 [ -z "$COMPAT" ] && fail "Missing compatibility file for ML system \"$ML_SYSTEM\"!"
 
-exec isabelle -e "use\"$COMPAT\"; use\"ROOT.ML\" handle _ => exit 1;" -cq SYSTEM Pure
+exec isabelle \
+  -e "val ml_system = \"$ML_SYSTEM\";" \
+  -e "use\"$COMPAT\"; use\"ROOT.ML\" handle _ => exit 1;" \
+  -cq SYSTEM Pure