For x86 Darwin, we have a stack checking feature which re-uses some of this machinery around stack probing on Windows. Renaming this to be more appropriate for a generic feature.
The feature hasn't yet been upstreamed yet, it's tied quite closely with macOS so has been shipping with Apple clang for a few years now. This is one of the downstream patches we've had. The rest we will upstream in due course and when we do I'll add a release note for it.