[debian-mysql] Bug#1006388: libmariadb-dev-compat: multi-arch is not present or not working. I am unable to install multiple architectures into Docker "debian:stable" as an example.

[Dick Hollenbeck]

Package: libmariadb-dev-compat
Version: 1:10.5.12-0+deb11u1
Severity: important
X-Debbugs-Cc: dick at softplc.com

Dear Maintainer,

I am preparing a C++ toolkit docker container that supports multiple debian architectures
for cross compiling.  My goal is libpoco-dev, but after drilling down I see that subject
package is why the higher level package architectures cannot be installed concurrently.

Note that the package manager de-installs prior architectures before the next architecture
is attempted.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?

Run the following Dockerfile with "docker build":



FROM debian:stable

# A package to test for MultiArch support, typically limited to libraries only.
ENV PKG="libmariadb-dev-compat"

# A set of machine architectures for testing MultiArch support
ENV ARCHS="amd64 armhf i386 arm64"

# Extend the architectures known to APT via --add-architecture, then install
# $PKG for each of these architectures

RUN for arch in $ARCHS; do \
        dpkg --add-architecture $arch; \
    done && \
    apt-get update && \
    DEBIAN_FRONTEND=noninteractive apt-get install \
        --yes --no-install-recommends apt-utils && \
    for arch in $ARCHS; do \
        DEBIAN_FRONTEND=noninteractive apt-get install \
            --yes --no-install-recommends $PKG:$arch \
        ; \
    done

CMD ["bash"]

   * What was the outcome of this action?

During the docker build, there are lines saying that prior architecture's
packages of the same name are being removed, for example:

The following packages will be REMOVED:
  libmariadb-dev:i386 libmariadb-dev-compat:i386


   * What outcome did you expect instead?

I expected that with proper multi-arch support, multiple architectures could be installed
concurrently into the system, in this case a docker container.


-- System Information:
Debian Release: 11.2
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 5.10.11-hardbook (SMP w/4 CPU threads; PREEMPT)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/bash
Init: systemd (via /run/systemd/system)