1 files changed, 15 insertions, 2 deletions

diff --git a/lisp/international/quail.el b/lisp/international/quail.el
index df5f009988d..77e69b04d6a 100644
--- a/lisp/international/quail.el
+++ b/lisp/international/quail.el
@@ -1062,8 +1062,21 @@ The returned value is a Quail map specific to KEY."
               (setq unread-command-events
                     (cons (aref quail-current-key len)
                           unread-command-events)))
-            (insert (or quail-current-str
-                        (substring quail-current-key 0 len))))
+            ;; Insert the translated sequence.
+            ;; It is a string containing multibyte characters.
+            ;; If enable-multibyte-characters, just insert it.
+            (if enable-multibyte-characters
+                (insert (or quail-current-str
+                            (substring quail-current-key 0 len)))
+              ;; Otherwise, in case the user is using a single-byte
+              ;; extended-ASCII character set,
+              ;; try inserting the translated character.
+              (let ((char (sref (or quail-current-str
+                                    (substring quail-current-key 0 len))
+                                0)))
+                (if (= (length (split-char char)) 2)
+                    (insert-char (logand char 127))
+                  (error "Cannot insert three-byte character in single-byte mode")))))
         (insert (or quail-current-str quail-current-key)))))
   (quail-update-guidance)
   (if control-flag