diff -r 5426d266dcc5 -r c911716d29bb lib/scripts/getsettings
--- a/lib/scripts/getsettings	Mon Nov 05 17:37:55 2018 +0100
+++ b/lib/scripts/getsettings	Mon Nov 05 20:53:16 2018 +0100
@@ -110,8 +110,8 @@
 fi
 
 #enforce ISABELLE_GHC
-if [ -d "$ISABELLE_STACK_ROOT" ]; then
-  if [ -f "$(standard_path "$(isabelle_stack path --programs)")/$ISABELLE_GHC_VERSION/bin/ghc" ]; then
+if [ -d "$ISABELLE_STACK_ROOT" -a -f "$ISABELLE_STACK_ROOT/ISABELLE_GHC_PROGRAMS" ]; then
+  if [ -f "$(cat "$ISABELLE_STACK_ROOT/ISABELLE_GHC_PROGRAMS")/$ISABELLE_GHC_VERSION/bin/ghc" ]; then
     ISABELLE_GHC="$ISABELLE_HOME/lib/Tools/ghc"
   fi
 fi