Hi Guile devs,

I'm hacking on GNU LilyPond and recently wondered if Guile could run
without Java finalization that prevents collection of chains of
unreachable objects. I found that the functionality is only needed once
the first guardian is created, so it's possible to delay enabling the
mode until then. This required some fixes to free functions that
assumed dependent objects to be freed only later (see first two
patches).
The third patch delays ensuring Java finalization to scm_make_guardian,
but doesn't disable it explicitly (it's on by default in bdwgc). This
could now be done right after GC_INIT(), but it's not clear (at least
to me) whether client applications actually rely it, so I think it's
better if that's not done in Guile itself.

Please consider applying, the fixes potentially also to stable-2.2.

Thanks
Jonas