# base gentoo image set up
FROM gentoo/portage:latest as portage
FROM gentoo/stage3:latest
COPY --from=portage /var/db/repos/gentoo /var/db/repos/gentoo

# emerge clang and distcc
RUN emerge -qv clang distcc

# create log file, update path and distcc links
RUN mkdir -p /var/log && touch /var/log/distccd.log && chown distcc:daemon /var/log/distccd.log
ENV ENV="/root/.bashrc"
RUN echo "source /etc/profile" > $ENV
RUN eselect compiler-shadow update

# run container starting distccd process and forwarding tcp port, example settings below to accept connections on local network:
# docker run -p 3632:3632 --rm -dt <container name> distccd --daemon --allow-private --log-file /var/log/distccd.log --log-level notice --no-detach

# consult gentoo wiki for setting up distcc on client

# test gcc and clang on gentoo client with some small package, like the below:
# emerge -v htop
# CC="clang" CXX="clang++" emerge -v htop