--- a/libcpp/include/cpp-id-data.h	Sun Aug 21 07:07:55 2011 +0900
+++ b/libcpp/include/cpp-id-data.h	Fri Oct 27 22:46:09 2017 +0900
@@ -1,6 +1,5 @@
 /* Structures that hang off cpp_identifier, for PCH.
-   Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2009 Free Software Foundation, Inc.
+   Copyright (C) 1986-2017 Free Software Foundation, Inc.
 
 This program is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
@@ -34,7 +33,9 @@
 /* Each macro definition is recorded in a cpp_macro structure.
    Variadic macros cannot occur with traditional cpp.  */
 struct GTY(()) cpp_macro {
-  /* Parameters, if any.  */
+  /* Parameters, if any.  If parameter names use extended identifiers,
+     the original spelling of those identifiers, not the canonical
+     UTF-8 spelling, goes here.  */
   cpp_hashnode ** GTY ((nested_ptr (union tree_node,
 		"%h ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT (%h)) : NULL",
 			"%h ? HT_IDENT_TO_GCC_IDENT (HT_NODE (%h)) : NULL"),