if r.nread > r.f.UncompressedSize64 {
		return 0, ErrFormat
	}
	if err == nil {
		return
	}
	if err == io.EOF {
		if r.nread != r.f.UncompressedSize64 {
			return 0, io.ErrUnexpectedEOF
		}
		if r.desr != nil {
			if err1 := readDataDescriptor(r.desr, r.f); err1 != nil {
				if err1 == io.EOF {
					err = io.ErrUnexpectedEOF
				} else {
					err = err1
				}
			} else if r.hash.Sum32() != r.f.CRC32 {

	f.Fuzz(func(t *testing.T, b []byte) {
		r := NewReader(bytes.NewReader(b))
		type file struct {
			header  *Header
			content []byte
		}
		files := []file{}
		for {
			hdr, err := r.Next()
			if err == io.EOF {
				break
			}
			if err != nil {
				return
			}
			buf := bytes.NewBuffer(nil)
			if _, err := io.Copy(buf, r); err != nil {
				continue
			}

			name := in.Stack.Text()
			macro := in.macros[name]
			if macro != nil {
				nesting++
				in.invokeMacro(macro)
				continue
			}
			fallthrough
		default:
			if tok == scanner.EOF && len(in.ifdefStack) > 0 {
				// We're skipping text but have run out of input with no #endif.
				in.Error("unclosed #ifdef or #ifndef")
			}
			in.beginningOfLine = tok == '\n'
			if in.enabled() {

		}
	}
	if err := tw.Close(); err != nil {
		log.Fatal(err)
	}

	// Open and iterate through the files in the archive.
	tr := tar.NewReader(&buf)
	for {
		hdr, err := tr.Next()
		if err == io.EOF {
			break // End of archive
		}
		if err != nil {
			log.Fatal(err)
		}
		fmt.Printf("Contents of %s:\n", hdr.Name)
		if _, err := io.Copy(os.Stdout, tr); err != nil {
			log.Fatal(err)
		}
		fmt.Println()

		}
	}

	// If the last fragment is a hole, then seek to 1-byte before EOF, and
	// read a single byte to ensure the file is the right size.
	if readLastByte && err == nil {
		_, err = mustReadFull(rs, []byte{0})
		sw.pos++
	}

	n = sw.pos - pos0
	switch {
	case err == io.EOF:
		return n, io.ErrUnexpectedEOF
	case err == ErrWriteTooLong:

		return nil, nil, err // EOF is okay here; exactly 0 bytes read
	}
	if bytes.Equal(tr.blk[:], zeroBlock[:]) {
		if _, err := io.ReadFull(tr.r, tr.blk[:]); err != nil {
			return nil, nil, err // EOF is okay here; exactly 1 block of zeros read
		}
		if bytes.Equal(tr.blk[:], zeroBlock[:]) {
			return nil, nil, io.EOF // normal EOF; exactly 2 block of zeros read
		}

// it resumes reading the next one down.
type Stack struct {
	tr []TokenReader
}

// Push adds tr to the top (end) of the input stack. (Popping happens automatically.)
func (s *Stack) Push(tr TokenReader) {
	s.tr = append(s.tr, tr)
}

func (s *Stack) Next() ScanToken {
	tos := s.tr[len(s.tr)-1]
	tok := tos.Next()
	for tok == scanner.EOF && len(s.tr) > 1 {
		tos.Close()

func IsRegisterShift(r ScanToken) bool {
	return ROT <= r && r <= LSH // Order looks backwards because these are negative.
}

func (t ScanToken) String() string {
	switch t {
	case scanner.EOF:
		return "EOF"
	case scanner.Ident:
		return "identifier"
	case scanner.Int:
		return "integer constant"
	case scanner.Float:
		return "float constant"
	case scanner.Char:
		return "rune constant"

	}
	err := s.Err()
	if err != testError {
		t.Fatalf("expected %q got %v", testError, err)
	}
}

// Test that an EOF is overridden by a user-generated scan error.
func TestErrAtEOF(t *testing.T) {
	s := NewScanner(strings.NewReader("1 2 33"))
	// This splitter will fail on last entry, after s.err==EOF.
	split := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
		advance, token, err = ScanWords(data, atEOF)

	{"$bar<ABI0>(SB)", "$bar<ABI0>(SB)"},
	{"$foo<ABIInternal>(SB)", "$foo<ABIInternal>(SB)"},
}

var amd64BadOperandTests = []badOperandTest{
	{"[", "register list: expected ']', found EOF"},
	{"[4", "register list: bad low register in `[4`"},
	{"[]", "register list: bad low register in `[]`"},
	{"[f-x]", "register list: bad low register in `[f`"},
	{"[r10-r13]", "register list: bad low register in `[r10`"},