class memory layout in vc 6.0

Hello,

I'm trying to figure out how vc 6.0 does class memory layout.

In order to explain what I'm doing right now, I'm going to use an example:

class base0
{
virtual void f();
};

class base1
{
};

class derived :
    public base0, // derived shares the vfptr with base0 when it is the
first base class
    public base1 // empty (when used as a base class we can use 0 size)
{
base1 m_member1; // sizeof(1), offset(4) (when used as a member, 0-sized
classes become 1-size classes)
// 3 bytes of padding
int m_member2; // sizeof(4), offset(8)
char m_member3;
// 3 bytes of padding

    virtual void f2();
};

sizeof(derived) = 16

also, alignment of a class is the maximum alignment of its members.

This example shows what I've gathered so far, yet there are some cases I've
encountered that I just don't understand.. I've even encountered situations
where offset of a base class is dependendant on classes that come AFTER it
in the class inheritance list, also, it seems there are situations where a
0-size base class does affect things, but how I don't know.

If someone can correct or add to what I've got so far, I'd appreciate it.

thanks,

--
Sigurd Lerstad