message: Add the SA_ONSTACK flag to SigAction so that stack overflow doesn't prevent unwinding.
diff: @@ -12,7 +12,7 @@ use nix::sys::signal::{
  pub unsafe fn install_sighandler() {
  let sa = SigAction::new(
  SigHandler::Handler(signal_trap_handler),
  - SaFlags::empty(),
  + SaFlags::SA_ONSTACK,
  SigSet::empty(),
  );
  sigaction(SIGFPE, &sa).unwrap();
  