(mail-bury): Test that rmail-summary-buffer is boundp.

1 files changed, 2 insertions, 1 deletions

diff --git a/lisp/mail/sendmail.el b/lisp/mail/sendmail.el
index 5c192cb76a4..653c630ed7e 100644
--- a/lisp/mail/sendmail.el
+++ b/lisp/mail/sendmail.el
@@ -334,7 +334,8 @@ Prefix arg means don't delete this window."
                (set-buffer (window-buffer (next-window (selected-window) 'not)))
                (setq rmail-flag (eq major-mode 'rmail-mode))
                (setq summary-buffer
-                     (and rmail-summary-buffer
+                     (and (boundp 'rmail-summary-buffer)
+                          rmail-summary-buffer
                           (buffer-name rmail-summary-buffer)
                           (not (get-buffer-window rmail-summary-buffer))
                           rmail-summary-buffer))))