diff -r b18f83985215 -r e00e1bf23d03 src/Pure/General/file.scala
--- a/src/Pure/General/file.scala	Wed Sep 30 14:49:39 2015 +0200
+++ b/src/Pure/General/file.scala	Wed Sep 30 20:02:39 2015 +0200
@@ -27,7 +27,7 @@
   def standard_path(platform_path: String): String =
     if (Platform.is_windows) {
       val Platform_Root = new Regex("(?i)" +
-        Pattern.quote(Isabelle_System.get_cygwin_root()) + """(?:\\+|\z)(.*)""")
+        Pattern.quote(Isabelle_System.cygwin_root()) + """(?:\\+|\z)(.*)""")
       val Drive = new Regex("""([a-zA-Z]):\\*(.*)""")
 
       platform_path.replace('/', '\\') match {
@@ -71,7 +71,7 @@
             result_path ++= root
             rest
           case path if path.startsWith("/") =>
-            result_path ++= Isabelle_System.get_cygwin_root()
+            result_path ++= Isabelle_System.cygwin_root()
             path
           case path => path
         }