bug#19774: 25.0.50; Emacs crashes when C-u <N> on a Gnus folder (reproducible)

[Sebastien Vauban]

Eli Zaretskii wrote:
>> From: Sebastien Vauban <sva-news@mygooglest.com>
>> Date: Wed, 04 Feb 2015 23:34:13 +0100
>> 
>> When pressing C-u 9 (for example) on a Gnus folder, Emacs crashes (right
>> after the key 9 has been pressed)... iff key-chord mode (20140929.2246)
>> is enabled.  There is clearly an interaction, as the Emacs crash won't
>> occur if key-chord is disabled...
>> 
>> And that did happen since that version of key-chord; it wasn't there
>> with the previous one -- which I don't know how to reinstall through
>> (M)ELPA...
>> 
>> As far as I know, only Gnus is affected by the bug.  I can use numerical
>> prefixes in many other situations without any crash.
>
> Any hope to get a reproducible recipe?

Wow, that was /really/ hard, but adding the following customization to
your .emacs should allow you to reproduce it:

--8<---------------cut here---------------start------------->8---
(add-to-list 'load-path "~/.emacs.d/elpa/key-chord-20140929.2246")
(require 'key-chord)
(key-chord-mode 1)                      ; NEEDED!
(with-eval-after-load "key-chord"
  (key-chord-define-global "x1" 'delete-other-windows)) ; NEEDED!

(add-to-list 'load-path "~/.emacs.d/elpa/guide-key-20150107.2235")
(add-to-list 'load-path "~/.emacs.d/elpa/dash-20141220.1452")
(add-to-list 'load-path "~/.emacs.d/elpa/popwin-20141227.2351")
(add-to-list 'load-path "~/.emacs.d/elpa/s-20140910.334")
(require 'guide-key)
(guide-key-mode 1)                      ; NEEDED!
--8<---------------cut here---------------end--------------->8---

(I don't think the versions really matter, except for Key-chord; hence,
you could remove the add-to-list if you use `package' to load both
`key-chord' and `guide-key'.)

After that, do:

1. Start up Gnus
2. Go onto a folder
3. Press `C-u 1' (the "1" seems to be important too; no problem with "9")