class and variable declaration( of same class type)

Question

Is this declaration correct in c++?

class Abc
{
struct xyz x;

};

struct xyz
{
Abc abc;
int instances;
};

I receive the following error. error: field 'x' has incomplete type

So, if I have usecase as above, how do I create it?

Answer 1

You cannot achieve this because there is a cyclic dependency between the two types. You can achieve this by using pointer to structure as member and forward declarations.