获取成员变量的地址和偏移地址

#include<iostream>
using namespace std;

struct Point3D{
int a;
int b;
int c;
};

int main(){

Point3D *p = NULL;
int offset = (int)(&(p)->c);
int i = (int)(&(p->c));
cout << &(p->c) << endl;
cout << i << endl;

cout << offset << endl;
cout << "............" << endl;
int j = (int)(&(*p).c);
cout << j << endl;

Point3D p3d;
int k = (int)(&p3d.c);
cout << k << endl;

return 0;

}

$ ./a
0x8
8
8
............
8
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