c++ - 如何在 C++ 中清理已删除的对象

Question

是否可以在 C++ 中将已删除对象的内存清零？我想这样做以在单元测试中重现核心转储:

//Some member variable of object-b is passed-by-pointer to object-a
//When object-b is deleted, that member variable is also deleted
//In my unit test code, I want to reproduce this
//even if I explicitly call delete on object-b
//accessBMemberVariable should coredump, but it doesn't
//I'm assuming even though object-b is deleted, it's still intact in memory
A *a = new A();
{
  B *b = new B(a);
  delete b;
}
a->accessBMemberVariable();

Answer 1

您可能应该覆盖 delete 运算符。

给定类 B 的示例:

class B
{
public:

  // your code
  ...

  // override delete
  void operator delete(void * p, size_t s)
  {
    ::memset(p, 0, s);
    ::operator delete(p, s);
  }
};

编辑:感谢 litb 指出这一点。