警告消息：如何删除已弃用的“withUnsafeMutableBytes”和已弃用的“withUnsafeBytes”？

问：

我正在将代码从以前的 Swift 版本更改为 Swift5。并且有一条警告消息，指出此代码不可用。我想更改此代码，但我不知道如何更改。

警告代码

 func pbkdf2(hash: CCPBKDFAlgorithm, password: String, salt: Data, keyByteCount: Int, round: Int) -> Data? {
        let passwordData = password.data(using: .utf8)!
        let derivedKeyData = Data(count: keyByteCount)
        var localVariables = derivedKeyData
        let derivationStatus = localVariables.withUnsafeMutableBytes { derivedKeyBytes  in
            salt.withUnsafeBytes { saltBytes in
                CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
                                     password, passwordData.count, saltBytes, salt.count,
                                     hash, UInt32(round),
                                     derivedKeyBytes, derivedKeyData.count)
            }
        }

        if (derivationStatus != 0) {
            Log.Error("\(derivationStatus)")
            return nil;
        }

        return localVariables
    }

警告消息：

“withUnsafeMutableBytes”已弃用：请改用withUnsafeMutableBytes<R>(_: (UnsafeMutableRawBufferPointer) throws -> R) rethrows -> R

“withUnsafeBytes”已弃用：请改用withUnsafeBytes<R>(_: (UnsafeRawBufferPointer) throws -> R) rethrows -> R

如何更改此代码以删除警告消息？

我尝试了很多东西，但错误发生了变化。

func pbkdf2(hash: CCPBKDFAlgorithm, password: String, salt: Data, keyByteCount: Int, round: Int) -> Data? {
  let passwordData = password.data(using: .utf8)!
  let derivedKeyData = Data(count: keyByteCount)
  var localVariables = derivedKeyData
  let derivationStatus = localVariables.withUnsafeMutableBytes { derivedKeyBytes  in
     let Mutable: UnsafeMutableRawPointer? = derivedKeyBytes.baseAddress
     salt.withUnsafeBytes { saltBytes in
           let raw: UnsafeRawPointer? = saltBytes.baseAddress
              CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
                                     password, passwordData.count, raw?.assumingMemoryBound(to: UInt8.self), salt.count,
                                     hash, UInt32(round),
                                     Mutable?.assumingMemoryBound(to: UInt8.self) , derivedKeyData.count)
            }
        }

        if (derivationStatus != 0) {
            Log.Error("\(derivationStatus)")
            return nil;
        }

        return localVariables
    }

错误信息：

二进制运算符“！=”不能应用于类型为“（）”和“Int”的操作数

警告消息：

常量“derivationStatus”推断为类型“（）”，其类型可能是 意外

我改变它对吗？我想我需要纠正比较，我应该如何纠正它？