How does Ruby handle stack frame allocation in C stack vs VM stack separation?

Ruby uses a VM-managed stack for Ruby frames while relying on C stack for native extensions.

Ruby VM frames exist in a managed stack structure inside CRuby, not directly on OS stack. However, C extensions execute on the native C stack. This dual-stack model requires careful bridging when calling between Ruby and C. It also impacts recursion limits, exception handling, and debugging stack traces, which must merge both stack worlds.