Ractor#close_outgoing should cancel waiting Ractor.yield. However,
yield a value by the Ractor's block should not cancel (to recognize
terminating Ractor, introduce rb_ractor_t::yield_atexit flag).
This implementation has memory corruption errors so and
it causes BUG on rare occasions. This commit skips
suspect tests on Github actions Compiler tests.
This commit introduces Ractor mechanism to run Ruby program in
parallel. See doc/ractor.md for more details about Ractor.
See ticket [Feature #17100] to see the implementation details
and discussions.
[Feature #17100]
This commit does not complete the implementation. You can find
many bugs on using Ractor. Also the specification will be changed
so that this feature is experimental. You will see a warning when
you make the first Ractor with `Ractor.new`.
I hope this feature can help programmers from thread-safety issues.