Question about Ruby GC safety

[uvlad7]

You mention in the README that "Ruby objects must be kept on the stack". This, in fact, is only required if your code might trigger GC. But I'm actually asking about how to ensure that this VALUE isn't optimized away by the compiler or stored in a register? AFAIK, in Ruby C API, volatile is used, but it's main purpose is a bit different and Rust's {read,write}_volatile covers it, but not Ruby's keep it on the stack need. But I'm not really sure about this as Ruby's docs - at least what I've found - don't cover this and I'm experienced in C. Can you please clarify the Rust part?

UPD: Found info about RB_GC_GUARD, maybe it's worth mentioning?