On Mon, Feb 20, 2017 at 05:06:48PM +0100, Ricardo Wurmus wrote:
> Since I lack an understanding of why the “guile” argument could ever
> purposefully be set to “#f” I cannot come up with a nice fix.  Instead
> of a nice fix I have found a really gross fix:
> 
> --8<---------------cut here---------------start------------->8---
> diff --git a/guix/download.scm b/guix/download.scm
> index 813f51f48..86f859881 100644
> --- a/guix/download.scm
> +++ b/guix/download.scm
> @@ -418,7 +418,10 @@ GnuTLS itself and its dependencies.  See <http://bugs.gnu.org/22774>."
>                         ;; hash of the expected result.
>                         #:verify-certificate? #f)))))
> 
> -  (mlet %store-monad ((guile (package->derivation guile system)))
> +  (mlet %store-monad ((guile (package->derivation
> +                              (or guile
> +                                  (@@ (gnu packages bootstrap) %bootstrap-guile))
> +                              system)))
>      (gexp->derivation file-name builder
>                        #:guile-for-build guile
>                        #:system system
> --8<---------------cut here---------------end--------------->8---

Based on discussion on #guix with Ricardo and Andy, I pushed this diff
as 9f05908fb1e3707cae593d94688748294717a546 on Ricardo's behalf.

I'm leaving the bug open until we find a better fix.