struct A {
  int m_a = 10;
};
struct B
{
  int m_a = 20;
};

struct C :public A, public B
{
  int m_a = 30;
};

//测试
  C c;

  debugPrintf("%x\n", &c);
  debugPrintf("%x\n", (A*)&c);
  debugPrintf("%x\n", (B*)&c);

  debugPrintf("%x\n", reinterpret_cast<B*>(&c));

  debugPrintf("%d\n", (&c)->m_a);
  debugPrintf("%d\n", ((A*)(&c))->m_a);
  debugPrintf("%d\n", ((B*)(&c))->m_a);
  debugPrintf("%d\n", reinterpret_cast<B*>(&c)->m_a);