Yes, exactly. I'm just a little curious since, without knowing anything about the code at all, unsigned long doesn't seem like a great choice. I'm sure the Ruby devs would know this though so I expect there must be some reason for it.

Here's the code: https://github.com/ruby/ruby/blob/trunk/include/ruby/ruby.h#...

It looks like uintptr_t support is there, just disabled for now.

Thanks - the fallback to long long explains it for me.