C++ 2-bit bitfield arrays possible?

Question

I have a struct of 2-bit bitfields like this:

struct MyStruct {
    unsigned __int32 info0  : 2;
    unsigned __int32 info1  : 2;
    unsigned __int32 info2          


        

Answer 1

If you can't use Paul R's answer for whatever reason, you can always use a custom accessor with a standard array :

static unsigned __int8 infos[30]; // 240 bits allocated

unsigned __int8 getInfo( unsigned short id_num )
{
    return (infos[id_num/4] >> ((2*id_num) % 8) ) & 0x3;
}
// setInfo left as an exercise.

(You may need to check the logic here, I haven't tested it.)