Re: Hang in make check

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: noloader@gmail.com,  emacs-devel@gnu.org
> Date: Tue, 30 Mar 2021 15:29:33 +0200
> 
> The test code snippet that's actually hanging is this:
> 
> (should (equal (progn (run-with-timer
>                        1 nil
>                        (lambda () (push '(t . ?\C-b) unread-command-events)))
>                       (read-event nil nil 2))
>                ?\C-b))
> 
> So the `read-event' hangs indefinitely, and then apparently never
> discovers that the run-with-timer has pushed something unto
> unread-command-events (because it's in that getchar?), I think.

Yes.  It's actually worse: _because_ the getchar call hangs, Emacs
doesn't get to running the timer function at all.

So I think the code needs to be modified, or maybe simply disabled
when system-configuration-features includes neither DBUS nor NOTIFY
nor THREADS.