locale warning and postgresql

[Myles English <mylesenglish@gmail.com>]

Hello,

I have always had trouble with my locale after installing guix on Arch
Linux (with zsh and a basic window manager, bspwm).  I have set
GUIX_LOCPATH in ~/.zshenv and it appears correct in my shell.  The
system-wide locale looks right.  When I install postgresql it gives the
usual "warning: failed to install locale: Invalid argument".  When I try
to initialise a database cluster, passing the locale doesn't work.

Does anyone using Arch Linux and a basic WM know which file to put
GUIX_LOCPATH in so that the warning goes away?

How can I find out what guix thinks its locale is or what are available?

Is there a way to use initdb even though there is a locale warning?

Shell experiments:

$ locale
LANG=en_GB.UTF-8
LC_CTYPE="en_GB.UTF-8"
LC_NUMERIC="en_GB.UTF-8"
LC_TIME="en_GB.UTF-8"
LC_COLLATE="en_GB.UTF-8"
LC_MONETARY="en_GB.UTF-8"
LC_MESSAGES="en_GB.UTF-8"
LC_PAPER="en_GB.UTF-8"
LC_NAME="en_GB.UTF-8"
LC_ADDRESS="en_GB.UTF-8"
LC_TELEPHONE="en_GB.UTF-8"
LC_MEASUREMENT="en_GB.UTF-8"
LC_IDENTIFICATION="en_GB.UTF-8"
LC_ALL=

$ echo $GUIX_LOCPATH
/home/myles/.guix-profile/lib/locale

$ guix package -i postgresql
warning: failed to install locale: Invalid argument
The following package will be upgraded:
   postgresql	9.5.3 -> 9.5.3	/gnu/store/sfgg20a7jnwfisajsvqdijjm2zj905az-postgresql-9.5.3

nothing to be done
guix package -i postgresql  7.56s user 0.22s system 107% cpu 7.213 total

$ which initdb
/home/myles/.guix-profile/bin/initdb

$ initdb --locale en_GB.UTF-8 -E UTF8 -D '/home/myles/pgdata-guix'
The files belonging to this database system will be owned by user "myles".
This user must also own the server process.

initdb: invalid locale name "en_GB.UTF-8"


$ initdb --locale en_GB -E UTF8 -D '/home/myles/pgdata-guix'
The files belonging to this database system will be owned by user "myles".
This user must also own the server process.

initdb: invalid locale name "en_GB"


$ initdb -E UTF8 -D '/home/myles/pgdata-guix'
The files belonging to this database system will be owned by user "myles".
This user must also own the server process.

initdb: invalid locale settings; check LANG and LC_* environment variables


Thanks,

Myles