bug#18373: desktop-create-buffer: may call bury-buffer on a just killed buffer (?)

[Ivan Shmakov]

Package:  emacs
Severity: minor
Tags: patch

        Currently, desktop-create-buffer calls bury-buffer on every
        buffer listed in a saved version of (buffer-list) so to restore
        the order of buffers:

  1375  ;; Restore buffer list order with new buffer at end. Don't change
  1376  ;; the order for old desktop files (old desktop module behavior).
  1377  (unless (< desktop-file-version 206)
  1378    (mapc 'bury-buffer buffer-list)
  1379    (when result (bury-buffer result)))

        This, however, fails – should one or more of these buffers be
        killed after the list is saved but before it’s processed, – as
        happens with some (presumably temporary) buffers used by
        url-retrieve, which is in turn used while restoring EWW buffers
        per [1].  (Please note that the patch there is broken, though.)

        The patch MIMEd seems to fix the issue for me, although I’m not
        as of yet certain that no buffer can be killed in between the
        buffer-live-p check and the bury-buffer call.

[1] http://debbugs.gnu.org/18010

-- 
FSF associate member #7257  http://boycottsystemd.org/  … 3013 B6A0 230E 334A

--- a/lisp/desktop.el
+++ b/lisp/desktop.el
@@ -1375,7 +1375,10 @@ after that many seconds of idle time."
        ;; Restore buffer list order with new buffer at end. Don't change
        ;; the order for old desktop files (old desktop module behavior).
        (unless (< desktop-file-version 206)
-         (mapc 'bury-buffer buffer-list)
+         (mapc (lambda (buf)
+                 (and (buffer-live-p buf)
+                      (bury-buffer buf)))
+               buffer-list)
          (when result (bury-buffer result)))
        (when result
          (unless (or desktop-first-buffer (< desktop-file-version 206))