Library packages still have ABI differences despite the best effort to track
them, and often migrate undetected.  Reasons for that might be

  - No symbols files provided in the package.
  - No easy way to write a symbols file for C++, and unable
    to differentiate between real issues and artifacts due to
    compiler changes.
  - Intentionally ignored ABI changes ("it's not part of the ABI")

A first step could be to just run abigail on such packages, report issues but
not block on those, to get an idea for possible issues.

An alternative could be to add abigail support to the packaging, as an
alternative to symbols files.  That would either require a new packaging helper
dh_abigail, or integration into dpkg/debhelper.  But maybe this isn't just an
alternative, but a separate step.

Hi,

Similar to piuparts and autopkgtest (and soon reproducibility), I'm open
to add this to britney2. However, somebody would need to setup and
maintain the infrastructure and we'd have to agree on an interface for
britney2 to query.

Paul