// for server that is started with `--no-compat`.
	if !etag.ContentMD5Requested(r.Header) && (crypto.S3KMS.IsRequested(r.Header) || crypto.SSEC.IsRequested(r.Header) || !globalServerCtxt.StrictS3Compat) {
		forceMD5 = mustGetUUIDBytes()
	}
	hashReader, err := hash.NewReaderWithOpts(ctx, reader, hash.Options{
		Size:       size,
		MD5Hex:     md5hex,
		SHA256Hex:  sha256hex,
		ActualSize: actualSize,
		DisableMD5: false,