func TestIndexByteBig(t *testing.T) {
	var n = 1024
	if testing.Short() {
		n = 128
	}
	b := make([]byte, n)
	for i := 0; i < n; i++ {
		// different start alignments
		b1 := b[i:]
		for j := 0; j < len(b1); j++ {
			b1[j] = 'x'
			pos := IndexByte(b1, 'x')
			if pos != j {
				t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
			}
			b1[j] = 0

	// more efficient, possibly due to cache effects.
	start := -1 // valid span start if >= 0
	for i := 0; i < len(s); {
		size := 1
		r := rune(s[i])
		if r >= utf8.RuneSelf {
			r, size = utf8.DecodeRune(s[i:])
		}
		if f(r) {
			if start >= 0 {
				spans = append(spans, span{start, i})
				start = -1
			}
		} else {
			if start < 0 {
				start = i
			}
		}
		i += size
	}

		add := len(p)
		if add > space {
			add = space
		}
		ss.buf = append(ss.buf, p[:add]...)
		p = p[add:]
	}
	for len(p) > 0 {
		n := copy(ss.buf[ss.start:], p)
		p = p[n:]
		ss.start += n
		if ss.start == ss.keep {
			ss.start = 0
		}
	}
	return
}

// generatesZip64 reports whether f wrote a zip64 file.
// f is also responsible for closing w.

	for _, op := range operands {
		p.start(op)
		if name, abi, ok := p.funcAddress(); ok {
			fmt.Fprintf(w, "ref %s %s\n", name, abi)
		}
	}
}

func (p *Parser) start(operand []lex.Token) {
	p.input = operand
	p.inputPos = 0
}

// address parses the operand into a link address structure.
func (p *Parser) address(operand []lex.Token) obj.Addr {
	p.start(operand)
	addr := obj.Addr{}

_cgo_import.go, which looks like:

	//go:cgo_dynamic_linker "/lib64/ld-linux-x86-64.so.2"
	//go:cgo_import_dynamic puts puts#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic __libc_start_main __libc_start_main#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic stdout stdout#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic fflush fflush#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic _ _ "libpthread.so.0"

		t.Errorf("%v: OpenRaw error=%v", f.Name, err)
		return
	}
	start, err := f.DataOffset()
	if err != nil {
		t.Errorf("%v: DataOffset error=%v", f.Name, err)
		return
	}
	got, err := io.ReadAll(rw)
	if err != nil {
		t.Errorf("%v: OpenRaw ReadAll error=%v", f.Name, err)
		return
	}
	end := uint64(start) + f.CompressedSize64
	want := raw[start:end]
	if !bytes.Equal(got, want) {
		t.Logf("got %q", got)

	b := []byte{0, 1, 2, 3, 4}
	tmp := make([]byte, 5)
	for i := 0; i <= 5; i++ {
		for j := i; j <= 5; j++ {
			for k := 0; k <= 6; k++ {
				// 0 <= i <= j <= 5; 0 <= k <= 6
				// Check that if we start with a buffer
				// of length j at offset i and ask for
				// Next(k), we get the right bytes.
				buf := NewBuffer(b[0:j])
				n, _ := buf.Read(tmp[0:i])
				if n != i {
					t.Fatalf("Read %d returned %d", i, n)

			return err
		}
		if _, err := io.WriteString(w.cw, h.Comment); err != nil {
			return err
		}
	}
	end := w.cw.count

	records := uint64(len(w.dir))
	size := uint64(end - start)
	offset := uint64(start)

	if f := w.testHookCloseSizeOffset; f != nil {
		f(size, offset)
	}

	if records >= uint16max || size >= uint32max || offset >= uint32max {
		var buf [directory64EndLen + directory64LocLen]byte