// We will fill out the correct size when we know it.
	dst = append(dst, 0xc6, 0, 0, 0, 0)
	dataOffset := len(dst)

	dst = msgp.AppendUint(dst, xlHeaderVersion)
	dst = msgp.AppendUint(dst, xlMetaVersion)
	dst = msgp.AppendInt(dst, len(x.versions))

	tmp := metaDataPoolGet()
	defer metaDataPoolPut(tmp)
	for _, ver := range x.versions {
		var err error

		// Add header