BV024structSizeUnionMadness

#include <iostream>

//struct Test
//{
//  uint8_t     f1; //1
//  uint16_t    f2; //2 [][][][]
//  uint8_t     f3; //1 [][][][]
//  uint32_t    f4; //4 [][][][]
//  uint8_t     f5; //1 [][][][]
//                  //9
//};
//  0           4       7   8           16
//  ([][][][])  ([][][][])  ([][][][])  ([][][][])

struct Test
{
    uint8_t     f5; //1
    uint8_t     f1; //1
    uint8_t     f3; //1 [5][*][*][*]
    uint16_t    f2; //2 [*][*][*][*]
    uint32_t    f4; //4 [4][4][4][4]
                    //9
};

union Buffer
{
    uint8_t bytes[4];
    uint16_t words[2];
    uint32_t buffer;
};


int main()
{
    Buffer buf;
    buf.bytes[0] = 0;
    buf.bytes[1] = 0;
    buf.bytes[2] = 0;
    buf.bytes[3] = 0;

    std::cout << buf.words[0] << '\n';
    std::cout << buf.words[1] << '\n';

    buf.words[0] = 65535;
    buf.words[1] = 65535;

    std::cout << (int)buf.bytes[0] << '\n';
    std::cout << (int)buf.bytes[1] << '\n';
    std::cout << (int)buf.bytes[2] << '\n';
    std::cout << (int)buf.bytes[3] << '\n';


    //std::cout << "sizeof(Test) = " << sizeof(Test) << '\n';

    //std::cout << "sizeof(uint8_t) = " << sizeof(uint8_t) << '\n';
    //std::cout << "sizeof(uint16_t) = " << sizeof(uint16_t) << '\n';
    //std::cout << "sizeof(uint32_t) = " << sizeof(uint32_t) << '\n';

    return 0;
}