If a reference marked weak becomes a special const, it will crash because
it is not a GC handled object. We should skip special consts here.
870a79426b
And get rid of the `obj_to_id_tbl`
It's no longer needed, the `object_id` is now stored inline
in the object alongside instance variables.
We still need the inverse table in case `_id2ref` is invoked, but
we lazily build it by walking the heap if that happens.
The `object_id` concern is also no longer a GC implementation
concern, but a generic implementation.
Co-Authored-By: Matt Valentine-House <matt@eightbitraptor.com>
This commit adds extconf.rb for both the default GC and and MMTk to build
the external GC. This allows common.mk to not need to contain any
implementation-specific build configuration.
db6a29b4a9
