diff --git a/src/cpp.c b/src/cpp.c
index 9f67d11fd35339d2679a8fbffb9f8f57fae52a30..2f4dc34e01ff5986c84ee8047a84f54dc1d6e062 100644
--- a/src/cpp.c
+++ b/src/cpp.c
@@ -2,7 +2,7 @@
 || This file is part of Pike. For copyright information see COPYRIGHT.
 || Pike is distributed under GPL, LGPL and MPL. See the file COPYING
 || for more information.
-|| $Id: cpp.c,v 1.171 2008/06/12 14:00:06 nilsson Exp $
+|| $Id: cpp.c,v 1.172 2008/06/12 17:09:11 nilsson Exp $
 */
 
 #include "global.h"
@@ -1670,6 +1670,11 @@ static void insert_current_major(struct cpp *this,
  *! This define contains the file path and name of the source file.
  */
 
+/*! @decl constant __DIR__
+ *!
+ *! This define contains the directory path of the source file.
+ */
+
 /*! @decl constant __DATE__
  *!
  *! This define contains the current date at the time of compilation,