diff --git a/UPGRADING b/UPGRADING
index 790803e3957..bc642aac25e 100755
--- a/UPGRADING
+++ b/UPGRADING
@@ -174,6 +174,9 @@ PHP 5.5 UPGRADE NOTES
 - cURL:
   - curl_file_create
 
+- GD
+  - imageflip
+
 - Hash:
   - hash_pbkdf2()