src/Pure/ProofGeneral/pgip_isabelle.ML

         val (url,descr) =
             (case Position.file_of pos of
                NONE => (NONE, NONE)
              | SOME fname =>
                let val path = Path.explode fname in
-                 case ThyLoad.check_file NONE path of
+                 case ThyLoad.check_file [] path of
                    SOME _ => (SOME (PgipTypes.pgipurl_of_path path), NONE)
                  | NONE => (NONE, SOME fname)
                end);
     in
         { descr=descr, url=url, line=line, column=NONE, char=NONE, length=NONE }