85, 120, 0, 0, // tag 30805 size 0
		},
	}
	testValidHeader(&h, t)
}

// Just benchmarking how fast the Zip64 test above is. Not related to
// our zip performance, since the test above disabled CRC32 and flate.
func BenchmarkZip64Test(b *testing.B) {
	for i := 0; i < b.N; i++ {
		testZip64(b, 1<<26)
	}
}

func BenchmarkZip64TestSizes(b *testing.B) {
	for _, size := range []int64{1 << 12, 1 << 20, 1 << 26} {

	// Create a new zip archive.
	w := zip.NewWriter(buf)

	// Register a custom Deflate compressor.
	w.RegisterCompressor(zip.Deflate, func(out io.Writer) (io.WriteCloser, error) {
		return flate.NewWriter(out, flate.BestCompression)
	})

	// Proceed to add files to w.

var flateWriterPool sync.Pool

func newFlateWriter(w io.Writer) io.WriteCloser {
	fw, ok := flateWriterPool.Get().(*flate.Writer)
	if ok {
		fw.Reset(w)
	} else {
		fw, _ = flate.NewWriter(w, 5)
	}
	return &pooledFlateWriter{fw: fw}
}

type pooledFlateWriter struct {
	mu sync.Mutex // guards Close and Write
	fw *flate.Writer
}

func (w *pooledFlateWriter) Write(p []byte) (n int, err error) {
	w.mu.Lock()

		if f.method == Deflate {
			var buf bytes.Buffer
			w, err := flate.NewWriter(&buf, flate.BestSpeed)
			if err != nil {
				t.Fatalf("flate.NewWriter err = %v", err)
			}
			_, err = w.Write(f.content)
			if err != nil {
				t.Fatalf("flate Write err = %v", err)
			}
			err = w.Close()
			if err != nil {
				t.Fatalf("flate Writer.Close err = %v", err)
			}
			compressedContent = buf.Bytes()

	// be mangled. Any existing identifier that already has the same name on
	// the C-side will cause the Go-mangled version to be prefixed with _.
	// (e.g. in a struct with fields '_type' and 'type', the latter would be
	// rendered as '__type' in Go).
	ident := make(map[string]string)
	used := make(map[string]bool)
	for _, f := range dt.Field {
		ident[f.Name] = f.Name
		used[f.Name] = true
	}

	// think, see e.g. comments in zipfile.c:putextended() and
	// https://bugs.openjdk.org/browse/JDK-7073588.
	// The approach here is to write 8 byte sizes if needed without
	// adding a zip64 extra in the local header (too late anyway).
	var buf []byte
	if w.isZip64() {
		buf = make([]byte, dataDescriptor64Len)
	} else {
		buf = make([]byte, dataDescriptorLen)
	}
	b := writeBuf(buf)