On Tue, Sep 05, 2017 at 10:59:54AM -0400, Ricardo Wurmus wrote:
> rekado pushed a commit to branch master
> in repository guix.
>
> commit fa67d5654176b4b815832eaf259188e1486c65ab
> Author: Ricardo Wurmus <rekado@elephly.net>
> Date:   Tue Jul 25 10:15:58 2017 +0200
>
>     gnu: elogind: Update to 232.3.
>
>     * gnu/packages/freedesktop.scm (elogind): Update to 232.3.
>     [home-page]: Use new upstream home page.
>     [arguments]: Disable tests, add new required configure flags; add build phase
>     "autogen".
>     [native-inputs]: Add autoconf, automake, libtool, and python.

According to `git bisect`, this update broke several packages related to
FreeDesktop and GNOME.

Specifically, those packages all require libcap to be available now. The
list of affected packages can be found with `git grep libcap`, since
they all had libcap added to their inputs.

I found that propagating libcap from elogind fixed some of the build
failures and not others.