Ruby should build without thread support (aka minix)
I tried to ./configure ruby on Minix 3.2.1,
The configure failed, because minix does not yet implement threads.
I'd like to suggest that ruby should still build on platforms without threads.
AFAIK the language does not yet require thread support in itself,
but maybe the new GC does require it.
So we might want to look up,
where the dependencies on threading really are.