doc: guix: Troubleshooting zdiff3 issue and uninstalling. #32442

   `--uninstall` [flag](https://guix.gnu.org/manual/devel/en/guix.html#index-uninstalling-Guix).

Fixed, thanks.

This is an interesting bug

Would it be possible to work around this in the build script somehow?

i guess not, i mean except by changing a global git setting there, which would be awful behavior...

Are there steps to reproduce on a fresh install? I tried Ubuntu 24.04, but it seems to pass:

    1  export DEBIAN_FRONTEND=noninteractive && apt update && apt install git vim htop guix bash curl make -y  && groupadd --system guixbuild && for i in `seq -w 1 10`; do useradd -g guixbuild -G guixbuild -d /var/empty -s `which nologin` -c "Guix build user $i" --system guixbuilder$i; done 
    2  git config --global merge.conflictstyle zdiff3 
    3  guix-daemon --build-users-group=guixbuild &
    4  guix time-machine --url=https://git.savannah.gnu.org/git/guix.git --commit=53396a22afc04536ddf75d8f82ad2eafa5082725  -- install hello

You can reproduce this issue as follows with podman:

Ubuntu container

# The reason a Dockerfile is needed is to get systemd installed and running in
# the container.
mkdir -p /tmp/ubuntu-systemd-container && cd /tmp/ubuntu-systemd-container
cat > ./Dockerfile << 'EOF'
FROM ubuntu:24.04
ENV DEBIAN_FRONTEND=noninteractive

RUN apt-get update
RUN apt-get install -y curl git gpg systemd make uidmap wget xz-utils
CMD ["/lib/systemd/systemd"]
EOF

# I haven't confirmed, but I don't think getting systemd running is as easy
# with docker
podman build -t ubuntu-systemd .
podman run -d --replace --name ubuntu-systemd --systemd=always ubuntu-systemd
podman exec -it ubuntu-systemd /bin/bash

Inside the container:

git config --global merge.conflictstyle zdiff3

# https://guix.gnu.org/manual/en/html_node/Binary-Installation.html#Binary-Installation-1
cd /tmp
wget -O guix-install.sh https://guix.gnu.org/install.sh
chmod +x guix-install.sh
yes '' | ./guix-install.sh

git clone https://github.com/bitcoin/bitcoin.git --depth 1 && cd bitcoin
HOSTS=x86_64-linux-gnu ./contrib/guix/guix-build

Fedora Container

Running the same commands as above once inside the container:

mkdir -p /tmp/fedora-systemd-container && cd /tmp/fedora-systemd-container
cat > ./Dockerfile << 'EOF'
FROM registry.fedoraproject.org/fedora:43
RUN dnf update -y
RUN dnf -y install git make systemd wget
CMD ["/lib/systemd/systemd"]
EOF

# I haven't confirmed, but I don't think getting systemd running is as easy
# with docker
podman build -t fedora-systemd .
podman run -d --replace --name fedora-systemd --systemd=always fedora-systemd
podman exec -it fedora-systemd /bin/bash

I believe this is no longer necessary.

On my Fedora 43 installation with the working Guix:

$ sestatus
SELinux status:                 enabled
SELinuxfs mount:                /sys/fs/selinux
SELinux root directory:         /etc/selinux
Loaded policy name:             targeted
Current mode:                   enforcing
Mode from config file:          enforcing
Policy MLS status:              enabled
Policy deny_unknown status:     allowed
Memory protection checking:     actual (secure)
Max kernel policy version:      35
$ guix describe
Generation 27	Dec 05 2025 14:13:44	(current)
  guix bd2edc9
    repository URL: https://git.guix.gnu.org/guix.git
    branch: master
    commit: bd2edc9e435402b48fd201b56ab486151512717a

Thanks for testing this, I've dropped this commit.

The default URL of the repository has been updated recently:

Updating channel 'guix' from Git repository at 'https://git.guix.gnu.org/guix.git'...

I'm not sure which is the "canonical" one, but git.guix.gnu.org redirects to codeberg and that is what I actually see in the error message:

Updating channel 'guix' from Git repository at 'https://codeberg.org/guix/guix.git'...
guix time-machine: error: Git error: unknown style 'zdiff3' given for 'merge.conflictstyle'

Thanks for catching this, I've updated the error message to what is actually printed. I think fixing the rest of the savannah->codeberg links could be done in a follow-up that also changes the guix time-machine --url in /contrib/guix/libexec/prelude.bash

running -> run [The sentence starts with an imperative ("Uninstall Guix itself...") and needs a parallel imperative verb; "or running" is a fragment — "or run" makes the coordination grammatical.]

The mistake I made was that or running... should be inside of the parentheses. The items in the parentheses don't "need" to be parallel with "Uninstall" even if you respect the parallel structure device as a rule (which it isn't.)

I moved the guix install script instructions inside the parentheses.

### zdiff3

   source, or running the Guix [install script][install-script] with the