How could a member method delete the object?

Question

I am currently studying COM and the following code confused me.

STDMETHODIMP _(ULONG) ComCar::Release()
{
  if(--m_refCount==0)
    delete this; // how could this "suicide" deletion be possible?
  return m_refCount;
}

I am wondering how could it be possible to delete an object instance within its member method? So I made the following experiment:

class A
{
public:
    void Suicide(void);
    void Echo(void);
    char name;
};

void A::Echo(void)
{
    ::printf("echo = %c\n",name);
}

void A::Suicide(void)
{
    delete this;
}

int main(void)
{
    A a;
    a.name='a';
    a.Suicide(); //failed
}

And the execution does failed at a.Suicide(). The debug report some "Debug Assertion Failed". Could someone shed some light on me? Cause I am totally a newbie on COM.

A related thread is here: Question about COM Release() method

Answer 1

Change your main's body to:

A* a = new A();
a->name='a';
a->Sucide();

You can only delete what was built by new, of course -- it makes no difference if that delete is in a member function or elsewhere.