Hi !

I may have found something that replaces finalizers. I followed Andy and
Amirouche advices and used guardians, as in guile-sqlite3.

The idea here is to create a guardian per pointer-type to finalize. A
pumper function that operates on this guardian is also created. This
pumper function knows the git_libgit2_xxx function to call to free the
pointers stored in guardians.

Finally, all pumpers are registered into a hook that is run before
shutting down.

I tried it on "repository" pointers but it can be easily extended to the
other finalizers.

WDYT ?

Thanks,

Mathieu