src/libstd/sys/unix/stack_overflow.rs is enabled on Linux, OS X, Bitrig, and OpenBSD targets only, because the implementation used to have its own signal-handling bindings that were only known to be correct on those targets. In #25784 I refactored the bindings and verified them for all current ports, I think we can turn this on on all current ports. This would enable handlers on Android, iOS, FreeBSD, and Dragonfly.

I don't have easy build infras for these myself, so I'm probably not going to do this immediately. But if someone wants to test one out and make sure that it works, I think it's just a matter of adding an OS to the #[cfg] and writing a program that segfaults.