}
	M.SetBit(M, int(n), 0)
	m := M.Uint64()
	return umagicData{s: int64(s), m: m}
}

func umagic8(c int8) umagicData   { return umagic(8, int64(c)) }
func umagic16(c int16) umagicData { return umagic(16, int64(c)) }
func umagic32(c int32) umagicData { return umagic(32, int64(c)) }
func umagic64(c int64) umagicData { return umagic(64, c) }

// For signed division, we use a similar strategy.
// First, we enforce a positive c.

	// Read File Header
	var magic [SAIAMAG]byte
	if _, err := sr.ReadAt(magic[:], 0); err != nil {
		return nil, err
	}

	arch := new(Archive)
	switch string(magic[:]) {
	case AIAMAGBIG:
		arch.magic = string(magic[:])
	case AIAMAG:
		return nil, fmt.Errorf("small AIX archive not supported")
	default:
		return nil, fmt.Errorf("unrecognised archive magic: 0x%x", magic)
	}

	case beMagic == go12magic:
		t.binary, possibleVersion = binary.BigEndian, ver12
	case leMagic == go116magic:
		t.binary, possibleVersion = binary.LittleEndian, ver116
	case beMagic == go116magic:
		t.binary, possibleVersion = binary.BigEndian, ver116
	case leMagic == go118magic:
		t.binary, possibleVersion = binary.LittleEndian, ver118
	case beMagic == go118magic:

		}

		if x.i != x.n {
			t.Fatalf("wrong x.i after swap: x.i=%#x x.n=%#x", x.i, x.n)
		}

		if x.before != _magic || x.after != _magic {
			t.Fatalf("wrong magic: %#x _ %#x != %#x _ %#x", x.before, x.after, _magic, _magic)
		}
	}
}

func TestStorepNoWB(t *testing.T) {
	var p [2]*int
	for i := range p {

const (
	magic         = "adl\x01"
	marshaledSize = len(magic) + 4
)

func (d *digest) MarshalBinary() ([]byte, error) {
	b := make([]byte, 0, marshaledSize)
	b = append(b, magic...)
	b = byteorder.BeAppendUint32(b, uint32(*d))
	return b, nil
}

func (d *digest) UnmarshalBinary(b []byte) error {
	if len(b) < len(magic) || string(b[:len(magic)]) != magic {

		k := SwapInt32(&x.i, delta)
		if x.i != delta || k != j {
			t.Fatalf("delta=%d i=%d j=%d k=%d", delta, x.i, j, k)
		}
		j = delta
	}
	if x.before != magic32 || x.after != magic32 {
		t.Fatalf("wrong magic: %#x _ %#x != %#x _ %#x", x.before, x.after, magic32, magic32)
	}
}

func TestSwapInt32Method(t *testing.T) {
	var x struct {
		before int32
		i      Int32
		after  int32
	}
	x.before = magic32

	return b, nil
}

func (d *digest) UnmarshalBinary(b []byte) error {
	if len(b) < len(magic) || string(b[:len(magic)]) != magic {
		return errors.New("crypto/md5: invalid hash state identifier")
	}
	if len(b) != marshaledSize {
		return errors.New("crypto/md5: invalid hash state size")
	}
	b = b[len(magic):]
	b, d.s[0] = consumeUint32(b)
	b, d.s[1] = consumeUint32(b)
	b, d.s[2] = consumeUint32(b)

	var frames []fakeTimeFrame
	for len(x) != 0 {
		if len(x) < 4+8+4 {
			return nil, errors.New("truncated header")
		}
		const magic = "\x00\x00PB"
		if string(x[:len(magic)]) != magic {
			return nil, errors.New("bad magic")
		}
		x = x[len(magic):]
		time := binary.BigEndian.Uint64(x)
		x = x[8:]
		dlen := binary.BigEndian.Uint32(x)
		x = x[4:]
		data := string(x[:dlen])
		x = x[dlen:]

	return b, nil
}

func (d *digest) UnmarshalBinary(b []byte) error {
	if len(b) < len(magic) || string(b[:len(magic)]) != magic {
		return errors.New("crypto/sha1: invalid hash state identifier")
	}
	if len(b) != marshaledSize {
		return errors.New("crypto/sha1: invalid hash state size")
	}
	b = b[len(magic):]
	b, d.h[0] = consumeUint32(b)
	b, d.h[1] = consumeUint32(b)
	b, d.h[2] = consumeUint32(b)

func (d *digest) BlockSize() int { return 1 }

func (d *digest) Reset() { d.crc = 0 }

const (
	magic         = "crc\x02"
	marshaledSize = len(magic) + 8 + 8
)

func (d *digest) MarshalBinary() ([]byte, error) {
	b := make([]byte, 0, marshaledSize)
	b = append(b, magic...)
	b = byteorder.BeAppendUint64(b, tableSum(d.tab))
	b = byteorder.BeAppendUint64(b, d.crc)
	return b, nil
}