dnsdist maybe doesn't build properly on s390x

[karelbilek]

I ran an AI code review bot on some private build changes on dnsdist and it found that s390x build doesn't properly work, because LuaJit is not properly installed.

From the bot output:

debian-bullseye/control installs liblua5.3-dev on s390x, but rules only switches away from luajit on arm64. On s390x, Meson is forced to -Dlua=luajit even though LuaJIT is not installed, so the package build fails.

This is barely an issue; I put it just as a discussion - I didn't even knew s390x build works? Does Meson even work on s390x? By googling, IBM System/390 was discontinued by IBM in 2004.

[karelbilek]

Meson seems to work on s390x

mesonbuild/meson#3897

[karelbilek]

Ah, s390x is just the family, there are existing supported mainframes with this family.

https://en.wikipedia.org/wiki/IBM_z13

I am not raising this as an issue here as I cannot replicate this (I am too lazy to figure out how to run this in qemu, if it's even possible)

[karelbilek]

it seems docker supports s390x natively! 😮 with --platform (which uses QEMU)

so with my PR here PowerDNS/pdns-builder#83 cross-building for s390x should "just work"

[karelbilek]

nope QEMU fails on some random step when doing rust builds. nevermind :)

[Habbie]

This diff makes the ubuntu-jammy dnsdist build (via builder/build.sh) fail later than on master, but then we get stuck on not having s390x Rust on our own mirror.

diff --git a/builder-support/dockerfiles/Dockerfile.dnsdist b/builder-support/dockerfiles/Dockerfile.dnsdist
index b1f56b2168..72f3fb2b34 100644
--- a/builder-support/dockerfiles/Dockerfile.dnsdist
+++ b/builder-support/dockerfiles/Dockerfile.dnsdist
@@ -3,7 +3,8 @@ ARG BUILDER_CACHE_BUSTER=
 
 RUN apk add --no-cache gcc g++ make tar autoconf automake protobuf-dev lua-dev \
                        libtool file boost-dev ragel python3 py3-yaml git libedit-dev \
-                       bash meson cargo
+                       bash meson cargo \
+                       python3-dev libffi-dev openssl-dev
 
 COPY . /dnsdist/
 WORKDIR /dnsdist/

Note that debian-bullseye/control is going away sometime early 2027. I did not check the newer control file for the problem you reported. Meanwhile Debian appears to be building packages just fine downstream.