// morestack would fail).
//
//go:nosplit
//go:nowritebarrierrec
func switchToCrashStack(fn func()) {
	me := getg()
	if crashingG.CompareAndSwapNoWB(nil, me) {
		switchToCrashStack0(fn) // should never return
		abort()
	}
	if crashingG.Load() == me {
		// recursive crashing. too bad.
		writeErrStr("fatal: recursive switchToCrashStack\n")
		abort()
	}