   Using Ptr To Objects in a C++ DLL
  Hi all,i was just playing around with c++ and just came 2 know that a non dll-interface class whose instance (just an object,not pointer to an object) is used in dll-interfaced class produces the warning C4251 Message: 'identifier' : class 'type' needs to have dll-interface to be used by clients of class 'type2'For Example:class __declspec(dllexport) CExp{public:CExp(void);public:~CExp(void);private:vector<int> m_nVec;   //C4251};But a pointer to object of a non dll-interface class whose instance is used in a dll-interfaced class doesn't produce any such warnings.....such asclass __declspec(dllexport) CExp{public:CExp(void);public:~CExp(void);private:vector<int>* m_nVec;   //No warnings here !!}; Can any1 plz tell me the reason behind this?   
  I found this guy's description of the problem, perhaps it will help you: Warning C4251