Dynamically extend Ruby VM stack
We (Keita Sugiyama and me) have presented the work on dynamically extending the Ruby VM stack today at RubyKaigi 2018 in Senday,
This is an issue to discuss when and how to integrate this into Ruby trunk, and what additional work is needed for this to happen. The code used for the experiments, based on r60436, is published at https://github.com/sugiyama-k/ruby/tree/chaining. Keita is working on adapting it to HEAD, and we expect to publish that version soon.