There is up to date ... And up to date😉 funnily enough I run a near bleeding edge version of Emacs from home brew and org 8.2.10 from Melpa. 

On Thursday, February 11, 2016, Thorsten Jolitz <tjolitz@gmail.com> wrote:
John Kitchin <jkitchin@andrew.cmu.edu> writes:

> On Wed, Feb 10, 2016 at 3:13 PM, Thorsten Jolitz <tjolitz@gmail.com>
> wrote:
>
>     #+BEGIN_SRC emacs-lisp
>     (defun my-foo (_)
>     "Hello World.
>     Argument _ unknown argument."
>     (+ 1 1))
>     #+END_SRC
>
> strange. in Emacs 25.1, I am pretty sure I get no errors from
> checkdoc.

Maybe not so strange, since I'm on:

,----
| GNU Emacs 24.5.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.16.6)
|  of 2015-09-10 on foutrelis
`----

And I thought with Archlinux I'm always up-to-date ...

--
cheers,
Thorsten




--
John

-----------------------------------
Professor John Kitchin 
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803
@johnkitchin
http://kitchingroup.cheme.cmu.edu