Of course is can be completely reasonable to ship with a known bug, which is why my initial reaction to the OP was: why are you bringing this up here?
However, not all bugs are made equal and this one seems relatively likely to actually cause problems for users. Wouldn't someone running some service and handling say 10 requests/second, while using the regex global variables, run into this bug on a daily basis?
So I guess I'm just interested in how such a decision is made: what bugs get shipped and which block a release?
If this bug would reasonably cause problems in such a situation and if the policy of JRuby is to ship anyway, that seems to be a relevant piece of information to consider for someone using JRuby in production and considering whether to upgrade.
Perhaps one should always check the list of open bugs for the version of a compiler/interpreter one intends to start using, but I've never done so, haven't been bitten by a bug yet (AFAIK) and yet this one seems one that could be a problem. The main problem is of course that this may just be 'the curse of knowledge' in play.
So I guess I was being a bit dismissive towards OP, then I was sympathetic and now I'm mostly thinking about how I should handle this as someone using JRuby in production. Perhaps I should just ignore it. Perhaps I should investigate the set of concurrency tests and contribute a few. Perhaps I should be conservative and only use 'proven' JRuby versions. Perhaps I should learn to stop worrying and love the bomb :)
