uc.uc_sigmask = sigset_all

	var oset sigset
	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)

	lwp_mcontext_init(&uc.uc_mcontext, stk, mp, mp.g0, abi.FuncPCABI0(netbsdMstart))

	ret := retryOnEAGAIN(func() int32 {
		errno := lwp_create(unsafe.Pointer(&uc), _LWP_DETACHED, unsafe.Pointer(&mp.procid))
		// lwp_create returns negative errno
		return -errno
	})
	sigprocmask(_SIG_SETMASK, &oset, nil)
	if ret != 0 {

	// Disable signals during create, so that the new thread starts
	// with signals disabled. It will enable them in minit.
	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
	ret = retryOnEAGAIN(func() int32 {
		return pthread_create(&tid, &attr, abi.FuncPCABI0(tstart_sysvicall), unsafe.Pointer(mp))
	})
	sigprocmask(_SIG_SETMASK, &oset, nil)
	if ret != 0 {

var Closeonexec = closeonexec

func sigismember(mask *sigset, i int) bool {
	clear := *mask
	sigdelset(&clear, i)
	return clear != *mask
}

func Sigisblocked(i int) bool {
	var sigmask sigset
	sigprocmask(_SIG_SETMASK, nil, &sigmask)
	return sigismember(&sigmask, i)
}

type M = m

var waitForSigusr1 struct {
	rdpipe int32
	wrpipe int32
	mID    int64
}

// the stack is safe to reclaim.
//
//go:noescape
func exitThread(wait *atomic.Uint32)

//go:noescape
func obsdsigprocmask(how int32, new sigset) sigset

//go:nosplit
//go:nowritebarrierrec
func sigprocmask(how int32, new, old *sigset) {
	n := sigset(0)
	if new != nil {
		n = *new
	}
	r := obsdsigprocmask(how, n)
	if old != nil {
		*old = r
	}
}

func pipe2(flags int32) (r, w int32, errno int32)

	KeepAlive(new)
	KeepAlive(old)
}
func sigaction_trampoline()

//go:nosplit
//go:cgo_unsafe_args
func sigprocmask(how uint32, new *sigset, old *sigset) {
	// sigprocmask is called from sigsave, which is called from needm.
	// As such, we have to be able to run with no g here.
	asmcgocall_no_g(unsafe.Pointer(abi.FuncPCABI0(sigprocmask_trampoline)), unsafe.Pointer(&how))

				sigdelset(&sigBlocked, i)
			}
		}
		sigprocmask(_SIG_SETMASK, &sigBlocked, nil)
		for {
			select {
			case sig := <-enableSigChan:
				if sig > 0 {
					sigdelset(&sigBlocked, int(sig))
				}
			case sig := <-disableSigChan:
				if sig > 0 && blockableSig(sig) {
					sigaddset(&sigBlocked, int(sig))
				}
			}
			sigprocmask(_SIG_SETMASK, &sigBlocked, nil)

}

// On multi-thread program, sigprocmask must not be called.
// It's replaced by sigthreadmask.
func sigprocmask1(how, new, old uintptr)

//go:nosplit
func sigprocmask(how int32, new, old *sigset) {
	gp := getg()

	// Check the validity of m because it might be called during a cgo

//go:noescape
func timer_delete(timerid int32) int32

//go:noescape
func rtsigprocmask(how int32, new, old *sigset, size int32)

//go:nosplit
//go:nowritebarrierrec
func sigprocmask(how int32, new, old *sigset) {
	rtsigprocmask(how, new, old, int32(unsafe.Sizeof(*new)))
}

func raise(sig uint32)
func raiseproc(sig uint32)

//go:noescape

	ECALL
	BNE	T0, ZERO, fail
	RET
fail:
	WORD	$0	// crash

// func osyield()
TEXT runtime·osyield(SB),NOSPLIT|NOFRAME,$0
	MOV	$SYS_sched_yield, T0
	ECALL
	RET

// func sigprocmask(how int32, new, old *sigset)
TEXT runtime·sigprocmask(SB),NOSPLIT|NOFRAME,$0-24
	MOVW	how+0(FP), A0
	MOV	new+8(FP), A1
	MOV	old+16(FP), A2
	MOV	$SYS_sigprocmask, T0
	ECALL
	BNE	T0, ZERO, fail
	RET

	SVC
	BCS	fail
	RET
fail:
	MOVD	$0, R0
	MOVD	R0, (R0)	// crash

// func osyield()
TEXT runtime·osyield(SB),NOSPLIT|NOFRAME,$0
	MOVD	$SYS_sched_yield, R8
	SVC
	RET

// func sigprocmask(how int32, new, old *sigset)
TEXT runtime·sigprocmask(SB),NOSPLIT|NOFRAME,$0-24
	MOVW	how+0(FP), R0
	MOVD	new+8(FP), R1
	MOVD	old+16(FP), R2
	MOVD	$SYS_sigprocmask, R8
	SVC
	BCS	fail
	RET
fail: