After upgrading to VS 2017 I got the following error from this code (which has always been working perfectly)

byte[] HexStringToByteArray(string hex)
    {
        if (hex.Length % 2 == 1)
            throw new Exception("The binary key cannot have an odd number of digits");

        byte[] arr = new byte[hex.Length >> 1];

        for (int i = 0; i < hex.Length >> 1; ++i) // Error in this line
        {
            arr[i] = (byte)((GetHexVal(hex[i << 1]) << 4) + (GetHexVal(hex[(i << 1) + 1])));
        }

        return arr;
    }

Exception:

Error 1: The variable 'i' cannot be used with type arguments
Error 2: 'hex' is a variable but is used like a type    

the solution was to surround the expression by parentheses.

for (int i = 0; i < (hex.Length >> 1); ++i)

But that made me wonder is this a bug or a new functionality? Thanks.