QByteArray sum

[jefftee]

There is no native 8-bit integer type. Qt provides quint8, which is guaranteed to be an 8-bit unsigned value on any platform, but it's effectively an unsigned char type. So, use quint8 or an unsigned char if you *must* compute the sum using a single byte.

In my opinion, using an integer type for the sum and computing the remainder using sum % 256 is more straight forward in my opinion.