// trap into the kernel and then return back to userspace.
		//
		// But on older kernels, such as Linux 4.4.180 as used on many Synology
		// devices, calling readARM64Registers (specifically getisar0) will
		// cause a SIGILL and we'll die. So for older kernels, parse /proc/cpuinfo
		// instead.
		//
		// See golang/go#57336.
		if linuxKernelCanEmulateCPUID() {
			readARM64Registers()
		} else {
			readLinuxProcCPUInfo()
		}

	/* 1 */ {_SigNotify + _SigKill, "SIGHUP: terminal line hangup"},
	/* 2 */ {_SigNotify + _SigKill, "SIGINT: interrupt"},
	/* 3 */ {_SigNotify + _SigThrow, "SIGQUIT: quit"},
	/* 4 */ {_SigThrow + _SigUnblock, "SIGILL: illegal instruction"},
	/* 5 */ {_SigThrow + _SigUnblock, "SIGTRAP: trace trap"},
	/* 6 */ {_SigNotify + _SigThrow, "SIGABRT: abort"},
	/* 7 */ {_SigPanic + _SigUnblock, "SIGBUS: bus error"},

	/* 1 */ {_SigNotify + _SigKill, "SIGHUP: hangup"},
	/* 2 */ {_SigNotify + _SigKill, "SIGINT: interrupt (rubout)"},
	/* 3 */ {_SigNotify + _SigThrow, "SIGQUIT: quit (ASCII FS)"},
	/* 4 */ {_SigThrow + _SigUnblock, "SIGILL: illegal instruction (not reset when caught)"},
	/* 5 */ {_SigThrow + _SigUnblock, "SIGTRAP: trace trap (not reset when caught)"},
	/* 6 */ {_SigNotify + _SigThrow, "SIGABRT: used by abort, replace SIGIOT in the future"},

with a stack dump by pressing ^\.

# Default behavior of signals in Go programs

By default, a synchronous signal is converted into a run-time panic. A
SIGHUP, SIGINT, or SIGTERM signal causes the program to exit. A
SIGQUIT, SIGILL, SIGTRAP, SIGABRT, SIGSTKFLT, SIGEMT, or SIGSYS signal
causes the program to exit with a stack dump. A SIGTSTP, SIGTTIN, or
SIGTTOU signal gets the system default behavior (these signals are

// SIGSEGV is normally transformed into a panic that causes the process to exit
// with status 2 if not recovered, which we handle as a crash.
func isCrashSignal(signal os.Signal) bool {
	switch signal {
	case
		syscall.SIGILL,  // illegal instruction
		syscall.SIGTRAP, // breakpoint
		syscall.SIGABRT, // abort() called
		syscall.SIGBUS,  // invalid memory access (e.g., misaligned address)

	/*  1 */ {_SigNotify + _SigKill, "SIGHUP: terminal line hangup"},
	/*  2 */ {_SigNotify + _SigKill, "SIGINT: interrupt"},
	/*  3 */ {_SigNotify + _SigThrow, "SIGQUIT: quit"},
	/*  4 */ {_SigThrow + _SigUnblock, "SIGILL: illegal instruction"},
	/*  5 */ {_SigThrow + _SigUnblock, "SIGTRAP: trace trap"},
	/*  6 */ {_SigNotify + _SigThrow, "SIGABRT: abort"},
	/*  7 */ {_SigThrow, "SIGEMT"},

}

// A Signal is a number describing a process signal.
// It implements the [os.Signal] interface.
type Signal uint8

const (
	SIGNONE Signal = iota
	SIGHUP
	SIGINT
	SIGQUIT
	SIGILL
	SIGTRAP
	SIGABRT
	SIGBUS
	SIGFPE
	SIGKILL
	SIGUSR1
	SIGSEGV
	SIGUSR2
	SIGPIPE
	SIGALRM
	SIGTERM
	SIGCHLD
	SIGCONT
	SIGSTOP
	SIGTSTP
	SIGTTIN
	SIGTTOU

	_MAP_PRIVATE   = C.MAP_PRIVATE
	_MAP_FIXED     = C.MAP_FIXED
	_MADV_DONTNEED = C.MADV_DONTNEED

	_SIGHUP     = C.SIGHUP
	_SIGINT     = C.SIGINT
	_SIGQUIT    = C.SIGQUIT
	_SIGILL     = C.SIGILL
	_SIGTRAP    = C.SIGTRAP
	_SIGABRT    = C.SIGABRT
	_SIGBUS     = C.SIGBUS
	_SIGFPE     = C.SIGFPE
	_SIGKILL    = C.SIGKILL
	_SIGUSR1    = C.SIGUSR1
	_SIGSEGV    = C.SIGSEGV
	_SIGUSR2    = C.SIGUSR2

	_SIGHUP:     {_SigNotify + _SigKill, "SIGHUP: terminal line hangup"},
	_SIGINT:     {_SigNotify + _SigKill, "SIGINT: interrupt"},
	_SIGQUIT:    {_SigNotify + _SigThrow, "SIGQUIT: quit"},
	_SIGILL:     {_SigThrow + _SigUnblock, "SIGILL: illegal instruction"},
	_SIGTRAP:    {_SigThrow + _SigUnblock, "SIGTRAP: trace trap"},
	_SIGABRT:    {_SigNotify + _SigThrow, "SIGABRT: abort"},
	_SIGBUS:     {_SigPanic + _SigUnblock, "SIGBUS: bus error"},

	EINTRNODATA        = Errno(1159)
	ENOREUSE           = Errno(1160)
	ENOMOVE            = Errno(1161)
)

// Signals
const (
	SIGHUP    = Signal(1)
	SIGINT    = Signal(2)
	SIGABRT   = Signal(3)
	SIGILL    = Signal(4)
	SIGPOLL   = Signal(5)
	SIGURG    = Signal(6)
	SIGSTOP   = Signal(7)
	SIGFPE    = Signal(8)
	SIGKILL   = Signal(9)
	SIGBUS    = Signal(10)
	SIGSEGV   = Signal(11)
	SIGSYS    = Signal(12)