(set-language-environment):

Check for language environments that can't work in unibyte.

1 files changed, 6 insertions, 0 deletions

diff --git a/lisp/international/mule-cmds.el b/lisp/international/mule-cmds.el
index 94a2b4f9d12..e0c4145ce45 100644
--- a/lisp/international/mule-cmds.el
+++ b/lisp/international/mule-cmds.el
@@ -842,6 +842,12 @@ specifies the character set for the major languages of Western Europe."
     (setq language-name "English"))
   (if (null (get-language-info language-name 'setup-function))
       (error "Language environment not defined: %S" language-name))
+  (unless default-enable-multibyte-characters
+    (or (member (downcase language)
+                '("latin-1" "latin-2" "latin-3" "latin-4" "latin-5"))
+        (error "Language environment `%s' not supported in unibyte mode"))
+    (standard-display-european 1 (downcase language)))
+
   (if current-language-environment
       (let ((func (get-language-info current-language-environment
                                      'exit-function)))