* It used to be hardcoded since 0affbf9d2c7c5c618b8d3fe191e74d9ae8ad22fc
  but got removed in 23abf3d3fb82afcc26d35769f0dec59dd46de4bb
* This means that since that second commit, rb_iterate() was used unintentionally.

https://github.com/ruby/racc/commit/8816ced525