diff --git a/ChangeLog b/ChangeLog
index 50daa6d5a6..587725d61b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Feb 21 20:22:43 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* hash.c (hash_foreach_iter): fix signature.
+
 Tue Feb 21 19:39:34 2012  Tanaka Akira  <akr@fsij.org>
 
 	* ext/curses/curses.c (Init_curses): use curses_version() for
diff --git a/hash.c b/hash.c
index 235355a4b9..4959a2c1bc 100644
--- a/hash.c
+++ b/hash.c
@@ -152,8 +152,9 @@ struct hash_foreach_arg {
 };
 
 static int
-hash_foreach_iter(st_data_t key, st_data_t value, struct hash_foreach_arg *arg)
+hash_foreach_iter(st_data_t key, st_data_t value, st_data_t argp, int err)
 {
+    struct hash_foreach_arg *arg = (struct hash_foreach_arg *)argp;
     int status;
     st_table *tbl;