src/Pure/goal.ML

   in Output.status (implode (map (Markup.markup_only o props) markups)) end;
 
 in
 
 fun fork_params {name, pos, pri} e =
-  uninterruptible (fn _ => fn () =>
+  uninterruptible (fn _ => Position.setmp_thread_data pos (fn () =>
     let
       val id = the_default 0 (Position.parse_id pos);
       val _ = count_forked 1;
 
       val future =

                        List.app (Future.error_msg pos) (ML_Compiler.exn_messages_ids exn)));
               val _ = count_forked ~1;
             in Exn.release result end);
       val _ = status (Future.task_of future) [Markup.forked];
       val _ = register_forked id future;
-    in future end) ();
+    in future end)) ();
 
 fun fork pri e =
   fork_params {name = "Goal.fork", pos = Position.thread_data (), pri = pri} e;
 
 fun forked_count () = #1 (Synchronized.value forked_proofs);