https://bugs.gentoo.org/528374

--- a/csharp-mode.el
+++ b/csharp-mode.el
@@ -125,6 +125,9 @@
 		  (stringp byte-compile-dest-file))
 	     (cons (file-name-directory byte-compile-dest-file) load-path)
 	   load-path)))
+    (and (= emacs-major-version 24)
+	 (>= emacs-minor-version 4)
+	 (require 'cl))
     (load "cc-mode" nil t)
     (load "cc-fonts" nil t)
     (load "cc-langs" nil t)))