// frame metadata.
	throwTypeUser

	// throwTypeRuntime is a throw due to a problem with Go itself.
	//
	// These throws include as much information as possible to aid in
	// debugging the runtime, including runtime frames, system goroutines,
	// and frame metadata.
	throwTypeRuntime
)

// We have two different ways of doing defers. The older way involves creating a

	if g0.m.incgo && gp == g0.m.g0 && g0.m.curg != nil {
		if iscgo {
			print("signal arrived during external code execution\n")
		}
		gp = g0.m.curg
	}
	print("\n")

	g0.m.throwing = throwTypeRuntime
	g0.m.caughtsig.set(gp)

	level, _, docrash := gotraceback()
	if level > 0 {
		tracebacktrap(r.ip(), r.sp(), r.lr(), gp)
		tracebackothers(gp)
		dumpregs(r)
	}

	if docrash {

	t := atomic.Load(&traceback_cache)
	crash = t&tracebackCrash != 0
	all = gp.m.throwing >= throwTypeUser || t&tracebackAll != 0
	if gp.m.traceback != 0 {
		level = int32(gp.m.traceback)
	} else if gp.m.throwing >= throwTypeRuntime {
		// Always include runtime frames in runtime throws unless
		// otherwise overridden by m.traceback.
		level = 2
	} else {
		level = int32(t >> tracebackShift)
	}
	return
}

var (
	argc int32

	// was sent to us by a program (c.sigFromUser() is true);
	// in that case, if we didn't handle it in sigsend, we exit now.
	if flags&(_SigThrow|_SigPanic) == 0 {
		return
	}

	mp.throwing = throwTypeRuntime
	mp.caughtsig.set(gp)

	if crashing.Load() == 0 {
		startpanic_m()
	}

	gp = fatalsignal(sig, c, gp, mp)

	level, _, docrash := gotraceback()
	if level > 0 {
		goroutineheader(gp)