diff --git a/ChangeLog b/ChangeLog
index 4d1a51aa0d..3febc5723d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Mar 25 18:42:46 2016  Koichi ITO  <koic.ito@gmail.com>
+
+	* variable.c: Added documentation about order of `Module#constants`
+	  [ci skip][Bug #12121][ruby-dev:49505][fix GH-1301]
+
 Fri Mar 25 18:41:14 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* string.c (enc_succ_alnum_char): try to skip an invalid character
diff --git a/variable.c b/variable.c
index e0d0eded82..77fca62aa7 100644
--- a/variable.c
+++ b/variable.c
@@ -2058,6 +2058,9 @@ rb_const_list(void *data)
  *  modules (example at start of section), unless the <i>inherit</i>
  *  parameter is set to <code>false</code>.
  *
+ *  The implementation makes no guarantees about the order in which the
+ *  constants are yielded.
+ *
  *    IO.constants.include?(:SYNC)        #=> true
  *    IO.constants(false).include?(:SYNC) #=> false
  *
diff --git a/version.h b/version.h
index 01116a1fb4..e8422a6fba 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.1.9"
 #define RUBY_RELEASE_DATE "2016-03-25"
-#define RUBY_PATCHLEVEL 482
+#define RUBY_PATCHLEVEL 483
 
 #define RUBY_RELEASE_YEAR 2016
 #define RUBY_RELEASE_MONTH 3