src/Pure/Admin/build_history.scala

     verbose: Boolean = false,
     build_args: List[String] = Nil): List[(Process_Result, Path)] =
   {
     /* sanity checks */
 
-    if (File.eq(Path.explode("~~").file, hg.root.file))
+    if (File.eq(Path.explode("~~"), hg.root))
       error("Repository coincides with ISABELLE_HOME=" + Path.explode("~~").expand)
 
     for (threads <- threads_list if threads < 1) error("Bad threads value < 1: " + threads)
 
     if (heap < 100) error("Bad heap value < 100: " + heap)

         other_isabelle.bash(
           "env PATH=\"" + File.bash_path(Path.explode("~~/lib/dummy_stty").expand) + ":$PATH\" " +
             "bin/isabelle jedit -b" + (if (fresh) " -f" else ""),
           redirect = true, echo = verbose).check
 
-        Isabelle_System.rm_tree(isabelle_base_log.file)
+        Isabelle_System.rm_tree(isabelle_base_log)
       }
 
-      Isabelle_System.rm_tree(isabelle_output.file)
+      Isabelle_System.rm_tree(isabelle_output)
       Isabelle_System.mkdirs(isabelle_output)
 
 
       /* build */