* lisp/isearch.el (isearch-quote-char): Check character validity like in `quoted-insert'.

Fixes: debbugs:16677

lisp/ChangeLog

+2014-02-08  Juri Linkov  <juri@jurta.org>
+
+	* isearch.el (isearch-quote-char): Check character validity
+	like in `quoted-insert' (bug#16677).
+
 2014-02-08  Lars Ingebrigtsen  <larsi@gnus.org>
 
 	* files.el (find-file-visit-truename): Doc clarification (bug#14697).

lisp/isearch.el

@@ -2301,6 +2301,9 @@ before the command is executed globally with terminated Isearch."
 With argument, add COUNT copies of the character."
   (interactive "p")
   (let ((char (read-quoted-char (isearch-message t))))
+    (unless (characterp char)
+      (user-error "%s is not a valid character"
+		  (key-description (vector char))))
     ;; Assume character codes 0200 - 0377 stand for characters in some
     ;; single-byte character set, and convert them to Emacs
     ;; characters.