From ab19d387041f0d54aa0269bd8c11f2a605becb9d Mon Sep 17 00:00:00 2001
From: SHIBATA Hiroshi <hsbt@ruby-lang.org>
Date: Sat, 1 Jul 2017 16:45:13 +0900
Subject: [PATCH] History

---
 History.rdoc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/History.rdoc b/History.rdoc
index d1bf4b85f..d52c7e2a9 100644
--- a/History.rdoc
+++ b/History.rdoc
@@ -3,6 +3,7 @@
 ==== Enhancements:
 
 * Enabled to dependency chained by extensions. Pull request #39 by Petr Skocik.
+* Make all of string literals to frozen objects on Ruby 2.4 or later.
 
 ==== Bug fixes