diff -r 15656ad28691 -r b254a95b6e77 src/Pure/ML/ml_process.scala
--- a/src/Pure/ML/ml_process.scala	Sat Oct 05 15:34:54 2019 +0200
+++ b/src/Pure/ML/ml_process.scala	Sun Oct 06 14:17:58 2019 +0200
@@ -35,8 +35,7 @@
     val heaps: List[String] =
       if (raw_ml_system) Nil
       else {
-        val selection = Sessions.Selection(sessions = List(logic_name))
-        sessions_structure1.selection(selection).
+        sessions_structure1.selection(Sessions.Selection.session(logic_name)).
           build_requirements(List(logic_name)).
           map(a => File.platform_path(_store.the_heap(a)))
       }