LINUX_REBOOT_CMD_CAD_ON          = 0x89abcdef
	LINUX_REBOOT_CMD_HALT            = 0xcdef0123
	LINUX_REBOOT_CMD_KEXEC           = 0x45584543
	LINUX_REBOOT_CMD_POWER_OFF       = 0x4321fedc
	LINUX_REBOOT_CMD_RESTART         = 0x1234567
	LINUX_REBOOT_CMD_RESTART2        = 0xa1b2c3d4
	LINUX_REBOOT_CMD_SW_SUSPEND      = 0xd000fce2
	LINUX_REBOOT_MAGIC1              = 0xfee1dead
	LINUX_REBOOT_MAGIC2              = 0x28121969

	LINUX_REBOOT_CMD_CAD_ON          = 0x89abcdef
	LINUX_REBOOT_CMD_HALT            = 0xcdef0123
	LINUX_REBOOT_CMD_KEXEC           = 0x45584543
	LINUX_REBOOT_CMD_POWER_OFF       = 0x4321fedc
	LINUX_REBOOT_CMD_RESTART         = 0x1234567
	LINUX_REBOOT_CMD_RESTART2        = 0xa1b2c3d4
	LINUX_REBOOT_CMD_SW_SUSPEND      = 0xd000fce2
	LINUX_REBOOT_MAGIC1              = 0xfee1dead
	LINUX_REBOOT_MAGIC2              = 0x28121969

	LINUX_REBOOT_CMD_HALT             = 0xcdef0123
	LINUX_REBOOT_CMD_KEXEC            = 0x45584543
	LINUX_REBOOT_CMD_POWER_OFF        = 0x4321fedc
	LINUX_REBOOT_CMD_RESTART          = 0x1234567
	LINUX_REBOOT_CMD_RESTART2         = 0xa1b2c3d4
	LINUX_REBOOT_CMD_SW_SUSPEND       = 0xd000fce2
	LINUX_REBOOT_MAGIC1               = 0xfee1dead
	LINUX_REBOOT_MAGIC2               = 0x28121969

	LINUX_REBOOT_CMD_CAD_ON          = 0x89abcdef
	LINUX_REBOOT_CMD_HALT            = 0xcdef0123
	LINUX_REBOOT_CMD_KEXEC           = 0x45584543
	LINUX_REBOOT_CMD_POWER_OFF       = 0x4321fedc
	LINUX_REBOOT_CMD_RESTART         = 0x1234567
	LINUX_REBOOT_CMD_RESTART2        = 0xa1b2c3d4
	LINUX_REBOOT_CMD_SW_SUSPEND      = 0xd000fce2
	LINUX_REBOOT_MAGIC1              = 0xfee1dead
	LINUX_REBOOT_MAGIC2              = 0x28121969

	m[0] = 12345
	m[0] += 67890
	m[0] /= 123
	m[0] %= 456

	const want = (12345 + 67890) / 123 % 456
	if got := m[0]; got != want {
		t.Errorf("got %d, want %d", got, want)
	}
}

var sinkAppend bool

func TestMapAppendAssignment(t *testing.T) {
	m := make(map[int][]int, 0)

	m[0] = nil
	m[0] = append(m[0], 12345)
	m[0] = append(m[0], 67890)

//                 |     |     |     |     |
//                 -------     -------     |
//                    |           |        |
//                    5           6        |
//                    |           |        |
//                    -------------        |
//                          |              |
//                          7              |
//                          |              |
//                          ----------------
//                                 |

		// IPv4 field has value >255
		"192.168.300.1",
		// IPv4 with too many fields
		"192.168.0.1.5.6",
		// IPv6 with not enough fields
		"1:2:3:4:5:6:7",
		// IPv6 with too many fields
		"1:2:3:4:5:6:7:8:9",
		// IPv6 with 8 fields and a :: expander
		"1:2:3:4::5:6:7:8",
		// IPv6 with a field bigger than 2b
		"fe801::1",
		// IPv6 with non-hex values in field
		"fe80:tail:scal:e::",

	LINUX_REBOOT_CMD_HALT                       = 0xcdef0123
	LINUX_REBOOT_CMD_KEXEC                      = 0x45584543
	LINUX_REBOOT_CMD_POWER_OFF                  = 0x4321fedc
	LINUX_REBOOT_CMD_RESTART                    = 0x1234567
	LINUX_REBOOT_CMD_RESTART2                   = 0xa1b2c3d4
	LINUX_REBOOT_CMD_SW_SUSPEND                 = 0xd000fce2
	LINUX_REBOOT_MAGIC1                         = 0xfee1dead

		// if there is data following that NUL character.
		// This is reasonable as GNU long names are C-strings.
		file: "testdata/gnu-long-nul.tar",
		headers: []*Header{{
			Name:     "0123456789",
			Mode:     0644,
			Uid:      1000,
			Gid:      1000,
			ModTime:  time.Unix(1486082191, 0),
			Typeflag: '0',
			Uname:    "rawr",
			Gname:    "dsnet",
			Format:   FormatGNU,
		}},

			// \q, but we don't. We once rejected \_, but too many
			// programs and people insist on using it, so allow \_.
			return c, t, nil
		}

	// Octal escapes.
	case '1', '2', '3', '4', '5', '6', '7':
		// Single non-zero digit is a backreference; not supported
		if t == "" || t[0] < '0' || t[0] > '7' {
			break
		}
		fallthrough
	case '0':