         return (checkType, flagsCRC)
     }
 
-    private static func processBlock(_ blockHeaderSize: UInt8,
+    private static func processBlock(_ blockHeaderSize: Int,
                                      _ pointerData: DataWithPointer) throws -> (blockData: [UInt8], unpaddedSize: Int, uncompressedSize: Int) {
-        var blockBytes: [UInt8] = []
         let blockHeaderStartIndex = pointerData.index - 1
-        blockBytes.append(blockHeaderSize)
         guard blockHeaderSize >= 0x01 && blockHeaderSize <= 0xFF
             else { throw XZError.wrongFieldValue }
         let realBlockHeaderSize = (blockHeaderSize + 1) * 4
 
         let blockFlags = pointerData.byte()
-        blockBytes.append(blockFlags)
         /**
          Bit values 00, 01, 10, 11 indicate filters number from 1 to 4,
          so we actually need to add 1 to get filters' number.

        return Data(bytes: out)
    }

    private static func processStreamHeader(_ pointerData: DataWithPointer) throws -> (checkType: UInt8, flagsCRC: UInt32) {
        // Check magic number.
        guard pointerData.bytes(count: 6) == [0xFD, 0x37, 0x7A, 0x58, 0x5A, 0x00]
            else { throw XZError.wrongMagic }

            if i >= 9 || byte == 0x00 {
                throw XZError.multiByteIntegerError
            }
            result += (byte.toInt() & 0x7F) << (7 * i)
            i += 1
        }
        return result
    }

}
