Comment 1 for bug 2023576

https://buildd.debian.org/status/fetch.php?pkg=ruby-rack&arch=all&ver=3.0.0-1&stamp=1668029150&raw=0 shows ruby-rack 3.0.0-1 in experimental building with libruby3.1 amd64 3.1.2-3. We currently have libruby3.1 3.1.2-7. The changelog for libruby3.1 shows:

ruby3.1 (3.1.2-7) unstable; urgency=medium

  * Upload to unstable

 -- Antonio Terceiro <email address hidden> Sat, 25 Mar 2023 14:20:34 -0300

ruby3.1 (3.1.2-7~exp) experimental; urgency=medium

  * Update openssl extension to to 3.0.1 (Closes: #1032070)

 -- Antonio Terceiro <email address hidden> Sun, 05 Mar 2023 17:13:36 -0300

ruby3.1 (3.1.2-6) unstable; urgency=medium

  * Add missing dependencies for pkg-config test

 -- Antonio Terceiro <email address hidden> Thu, 26 Jan 2023 09:34:07 -0300

ruby3.1 (3.1.2-5) unstable; urgency=medium

  * Add autopkgtest to test pkg_config
  * Add build dependency on pkg-config from pkgconf.
    The absence of this build dependency made the check for whether
    pkg-config works fail (because it was not there) at the ./configure
    stage, making RbConfig::CONFIG["PKG_CONFIG"] empty, and therefore broke
    the usage of pkg_config() in extconf.rb scripts.
    This was noticed by Lucas Kanashiro (thanks!) in Ubuntu while rebuilding
    all Ruby packages to add ruby3.1 support, where ruby-augeas and
    ruby-libvirt failed to build.

 -- Antonio Terceiro <email address hidden> Wed, 25 Jan 2023 14:46:18 -0300

ruby3.1 (3.1.2-4) unstable; urgency=medium

  * Replace cross pkg-config patch with patches applied upstream
  * Apply upstream patch to fix TZ tests (Closes: #1028890)
  * Drop exclude for TestTimeTZ, not needed anymore
  * debian/libruby3.1.symbols: fix version of rb_gc_ractor_newobj_cache_clear
  * debian/tests/builtin-extensions: also require libraries
  * Add upstream patch to upgrade CGI extension to 0.3.5.
    This fixes an HTTP response splitting vulnerability in CGI [CVE-2021-33621]
    (Closes: #1024799)

 -- Antonio Terceiro <email address hidden> Sun, 15 Jan 2023 08:27:59 -0300

The same build failure is reproducible in Debian sid.

Also it turns out this is Debian bug #1030442 which has been fixed in the unstable version of ruby-rack but not the experimental version.