CI failing seemingly since July 2025

[jarzec]

All PR opened since July 2025 have CI failures related to CMake issues with finding Boost.

A proposing a solution (#866) was opened in July 2025.

@AzothAmmo If you are you’re short on bandwidth I would be happy to help with maintenance.

[AzothAmmo]

Looking into this a bit, #866 unfortunately no longer works for all cases but I have a WIP PR (#876) that will handle it. There are some other CI failures I will look into as well - these were sort of the evergreen issue that prevented me from taking any time to handle PRs in the past. These days it's pretty easy to get assistance with CI tooling, so I'll make a best effort stab at sprucing up the CI pipeline.

One issue is that a lot of the compilers cereal previously tested against are difficult to run in CI since they are so old, and I have no way of knowing which compilers are currently actually being used by users of cereal.

[AzothAmmo]

MSVC CI is fixed, have to look at OSX stuff now and then probably expand the CI matrix to include some more modern compilers.

[jarzec]

Cool, thanks!
In fact for newer clangs (>20) you will need a fix like the one from #872. There are other propositions for fixing this issue, but #872 seems best.