diff -r 530b575d8cff -r fb94d68314fa src/Pure/PIDE/protocol.scala
--- a/src/Pure/PIDE/protocol.scala	Mon Sep 16 19:48:09 2019 +0200
+++ b/src/Pure/PIDE/protocol.scala	Mon Sep 16 20:06:25 2019 +0200
@@ -239,13 +239,12 @@
 
   def session_base(resources: Resources)
   {
-    val base = resources.session_base.standard_path
     protocol_command("Prover.init_session_base",
       encode_sessions(resources.sessions_structure.session_positions),
       encode_table(resources.sessions_structure.dest_session_directories),
-      encode_list(base.doc_names),
-      encode_table(base.global_theories.toList),
-      encode_list(base.loaded_theories.keys))
+      encode_list(resources.session_base.doc_names),
+      encode_table(resources.session_base.global_theories.toList),
+      encode_list(resources.session_base.loaded_theories.keys))
   }