diff -r e3a9680d9ed8 -r 892b68f932f9 src/Pure/Tools/server_commands.scala
--- a/src/Pure/Tools/server_commands.scala	Sat Dec 29 14:58:51 2018 +0100
+++ b/src/Pure/Tools/server_commands.scala	Sat Dec 29 16:11:24 2018 +0100
@@ -113,15 +113,9 @@
         try { Session_Build.command(args.build, progress = progress)._3 }
         catch { case exn: Server.Error => error(exn.message) }
 
-      val session =
-        Headless.start_session(
-          base_info.options,
-          base_info.session,
-          session_dirs = base_info.dirs,
-          session_base = Some(base_info.check_base),
-          print_mode = args.print_mode,
-          progress = progress,
-          log = log)
+      val resources = Headless.Resources(base_info, log = log)
+
+      val session = resources.start_session(print_mode = args.print_mode, progress = progress)
 
       val id = UUID.random()