Question

I get this:

This is a sample code of the two classes:

main.h

class CControl
{
protected:
    int m_X;
    int m_Y;

public:
    void SetX( int X ) { m_X = X; }
    void SetY( int Y ) { m_Y = Y; }

    int GetX() { return m_X; }
    int GetY() { return m_Y; }

    CControl *m_ChildControls;
    CControl *m_NextSibling;
    CControl *m_PreviousSibling;
    CControl *m_Parent;
    CControl *m_FocusControl;
};

class CButton : public CControl
{
protected:
    bool m_Type;
    bool m_Selected;
    bool m_Focused;
public:
    CButton( bool Type );
    ~CButton();
};


CButton::CButton( bool Type )
{
}

This is just the declarations of the two classes (they’re not complete, but the problem comes in also in the full coded version).

main.cpp

#include <windows.h>
#include "main.h"

int main()
{
    CButton *g_Button;
    g_Button = new CButton( 1 );

    return 0;
}

This is just the application main func where I declare g_Button as a new CButton object for making a debugging analysis.

Answer 1

The pointers could be anything, because they’re not initialized.

The compiler generated default constructor for CControl doesn’t initialize POD members. You’d need to write your own:

CControl() : m_ChildControls(NULL),  m_NextSibling(NULL), m_PreviousSibling(NULL)
             m_Parent(NULL), m_FocusControl(NULL)
{
}