I'm having a problem when I try to include oniguruma (v6.9.2) in my ruby C extension.
The regexp `foo([a-z]+)` with input `foobar` will not capture `bar` when running in Debian GNU/Linux 9.
I think it's colliding with Ruby's onigmo lib (modified oniguruma). But I can only replicate the
problem in Linux not macOS (Darwin).
If this is interesting to someone I have a git repo with all tests and a Dockerfile
that can be found here: https://github.com/voke/ruby-onig-issue
Should it be possible to use a different version of oniguruma for my Ruby C extension?