diff --git a/ChangeLog b/ChangeLog
index d0de7f182f..b6c06feae9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Aug  5 19:11:01 2009  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* ruby.c (rb_stdio_set_default_encoding): declared.
+
 Wed Aug  5 18:46:01 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* debug.c (ruby_dummy_gdb_enums): made public.  [ruby-dev:39001]
diff --git a/ruby.c b/ruby.c
index 6839bfe323..35c7b457f5 100644
--- a/ruby.c
+++ b/ruby.c
@@ -1211,6 +1211,8 @@ rb_f_chomp(argc, argv)
     return str;
 }
 
+void rb_stdio_set_default_encoding();
+
 static VALUE
 process_options(int argc, char **argv, struct cmdline_options *opt)
 {