[DRE-maint] Bug#1017701: gitlab: Upgrade to 15.2.2: Error installing prometheus-client-mmap in configuration

[Maximilian Stein]

Package: gitlab
Version: 15.2.2+ds1-2~fto11+1
Severity: important

Dear Maintainer,

Unfortunately, upgrading to 15.2.2+ds1-2~fto11+1 fails for me since a
ruby extension cannot be built:



    Building native extensions. This could take a while...
    ERROR:  Error installing prometheus-client-mmap:
            ERROR: Failed to build gem native extension.

        current directory: /var/lib/gitlab/.gem/gems/prometheus-client-mmap-0.16.2/ext/fast_mmaped_file
    /usr/bin/ruby2.7 -I /usr/lib/ruby/vendor_ruby -r ./siteconf20220819-213524-100euls.rb extconf.rb
    mkmf.rb can't find header files for ruby at /usr/lib/ruby/include/ruby.h

    You might have to install separate package for the ruby development
    environment, ruby-dev or ruby-devel for example.

    extconf failed, exit code 1

    Gem files will remain installed in /var/lib/gitlab/.gem/gems/prometheus-client-mmap-0.16.2 for inspection.
    Results logged to /var/lib/gitlab/.gem/extensions/x86_64-linux/2.7.0/prometheus-client-mmap-0.16.2/gem_make.out



According to the log file, ruby-dev must be installed to compile a
ruby extension (which makes sense) — is this really necessary here?

I actually have the package ruby-prometheus-client-mmap installed
(version 0.15.0-1~fto11+1), which actually installs shared libraries,
so I wonder why compiling anything is necessary at all.

Can I assist somehow in investigating the issue further?

Thank you very much for your help!

Best
Maximilian