(debug): Bind unread-command-char to -1, not nil.

diff --git a/lisp/emacs-lisp/debug.el b/lisp/emacs-lisp/debug.el
index 1cbaf646a5dbf5d19035eb0237ff52221a573676..49c9646a88ad88ea17ead7b776ced0c4ddbeb3c6 100644 (file)
--- a/lisp/emacs-lisp/debug.el
+++ b/lisp/emacs-lisp/debug.el
@@ -81,7 +81,7 @@ first will be printed into the backtrace buffer."
        (debugger-outer-cursor-in-echo-area cursor-in-echo-area))
     ;; Don't let these magic variables affect the debugger itself.
     (let ((last-command nil) this-command track-mouse
-         unread-command-char unread-command-events
+         (unread-command-char -1) unread-command-events
          last-input-event last-command-event last-nonmenu-event
          last-event-frame
          (standard-input t) (standard-output t)