1 files changed, 1 insertions, 1 deletions

diff --git a/lisp/tar-mode.el b/lisp/tar-mode.el
index bd10737b548..4adad6fe374 100644
--- a/lisp/tar-mode.el
+++ b/lisp/tar-mode.el
@@ -696,7 +696,7 @@ appear on disk when you save the tar-file's buffer."
               (setq coding (or coding-system-for-read
                                (and set-auto-coding-function
                                     (funcall set-auto-coding-function
-                                             name (point-max)))))
+                                             name (- end start)))))
               (if (or (not coding)
                       (eq (coding-system-type coding) 'undecided))
                   (setq coding (detect-coding-region start end t)))