From f39d6be01d06026a64e08009b773dc6b7c9d7a2b Mon Sep 17 00:00:00 2001
From: "Richard M. Stallman" <rms@gnu.org>
Date: Mon, 4 Sep 2006 15:03:26 +0000
Subject: [PATCH] (kill-region): Explicitly test there is a region.

---
 lisp/simple.el | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lisp/simple.el b/lisp/simple.el
index 3e19a8573e5..956468070da 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2554,6 +2554,8 @@ text.  See `insert-for-yank'."
   ;; Pass point first, then mark, because the order matters
   ;; when calling kill-append.
   (interactive (list (point) (mark)))
+  (unless (and beg end)
+    (error "The mark is not set now, so there is no region"))
   (condition-case nil
       (let ((string (filter-buffer-substring beg end t)))
 	(when string			;STRING is nil if BEG = END
-- 
2.39.2