   Anyone know how to get rid of the dreaded C4251 warning?
  Hey,I've done some research on the subject already. I've found some macros exporting all the classes of the containers but it was not working since I have many DLLs. Anyone know how to remove  warning C4251: 'std::_List_nod<_Ty,_Alloc>::_Alnod' : class 'std::allocator<_Ty>' needs to have dll-interface to be used by clients of class 'std::_List_nod<_Ty,_Alloc>' aside from disabling the warning?   
  I'm assuming your developing for Win32 here. That warning is telling you that there is a mismatch of exported and non-exported items in a class. Generally something like this is the cause.class NotExported{ //... whatever};class __declspec(dllexport) ExportedClass{private:   // you are using a non-exported class by value as a member   // in an exported class.   NotExported foo;};You can fix the aforementioned code by making foo a pointer or reference to a NotExported instance. Or you could just declare NotExported as __declspec(dllexport) or whatever.Now this could also happen if one class is declared __declspec(dllimport) and the other is __declspec(dllexport). I would need to see some of your code to help you further.   ;  I tried these macros :#ifndef DllExportH#define DllExportH#if defined(_MSC_VER)#ifdef _DEBUG#  define class_it_base class#else#  define class_it_base struct#endif#define EXPORT_STL_VECTOR(declspec_, T_) template class declspec_ std::allocator<T_ >; template class declspec_ std::vector<T_ >;#define EXPORT_STL_VECTOR_CONST_ITERATOR(declspec_, T_) class_it_base declspec_ std::_Iterator_base; template class declspec_ std::_Vector_const_iterator<T_,std::allocator<T_ > >;#define EXPORT_STL_DEQUE(declspec_, T_) template class declspec_ std::allocator<T_ >; template class declspec_ std::allocator<T_* >; template class declspec_ std::deque<T_ >;#define EXPORT_STL_LIST(declspec_, T_) template class declspec_ std::allocator<T_ >; template class declspec_ std::allocator<std::_List_nod<T_,std::allocator<T_ > >::_Node>; template class declspec_ std::allocator<std::_List_nod<T_,std::allocator<T_ > >::_Node*>; template class declspec_ std::list<T_ >;#define EXPORT_STL_SET(declspec_, T_) template class declspec_ std::allocator<T_ >; template struct declspec_ std::less<T_ >; template class declspec_ std::allocator<std::_Tree_nod< std::_Tset_traits<T_, std::less<T_ >, std::allocator<T_ >, false> >::_Node>; template class declspec_ std::allocator<std::_Tree_ptr< std::_Tset_traits<T_, std::less<T_ >, std::allocator<T_ >, false> >::_Node*>; template class declspec_ std::set<T_ >;#define EXPORT_STL_MULTISET(declspec_, T_) template class declspec_ std::allocator<T_ >; template struct declspec_ std::less<T_ >; template class declspec_ std::allocator<std::_Tree_nod< std::_Tset_traits<T_, std::less<T_ >, std::allocator<T_ >, true> >::_Node>; template class declspec_ std::allocator<std::_Tree_ptr< std::_Tset_traits<T_, std::less<T_ >, std::allocator<T_ >, true> >::_Node*>; template class declspec_ std::multiset<T_ >;#define EXPORT_STL_MAP(declspec_, K_, V_) template struct declspec_ std::less<K_ >; template class declspec_ std::allocator<std::_Tree_nod< std::_Tmap_traits<K_, V_, std::less<K_ >, std::allocator<std::pair<const K_, V_ > >, false> >::_Node>; template class declspec_ std::allocator<std::_Tree_nod< std::_Tmap_traits<K_, V_, std::less<K_ >, std::allocator<std::pair<const K_, V_ > >, false> >::_Node*>; template class declspec_ std::allocator<std::pair<const K_, V_ > >; template class declspec_ std::map<K_, V_ >;#define EXPORT_STL_MAP_CONST_ITERATOR(declspec_, K_, V_) class_it_base declspec_ std::_Iterator_base; template class declspec_ std::_Tree<std::_Tmap_traits<K_, V_, std::less<K_>, std::allocator<std::pair<const K_, V_ > >, false> >::const_iterator;#define EXPORT_STL_MULTIMAP(declspec_, K_, V_) template struct declspec_ std::less<K_ >; template class declspec_ std::allocator<std::_Tree_nod< std::_Tmap_traits<K_, V_, std::less<K_ >, std::allocator<std::pair<const K_, V_ > >, true> >::_Node>; template class declspec_ std::allocator<std::_Tree_nod< std::_Tmap_traits<K_, V_, std::less<K_ >, std::allocator<std::pair<const K_, V_ > >, true> >::_Node*>; template class declspec_ std::allocator<std::pair<const K_, V_ > >; template class declspec_ std::multimap<K_, V_ >;#else#define EXPORT_STL_VECTOR(declspec_, T_)#define EXPORT_STL_VECTOR_CONST_ITERATOR(declspec_, T_)#define EXPORT_STL_DEQUE(declspec_, T_)#define EXPORT_STL_LIST(declspec_, T_)#define EXPORT_STL_SET(declspec_, T_)#define EXPORT_STL_MULTISET(declspec_, T_)#define EXPORT_STL_MAP(declspec_, K_, V_)#define EXPORT_STL_MAP_CONST_ITERATOR(declspec_, K_, V_)#define EXPORT_STL_MULTIMAP(declspec_, K_, V_)#endif#endifAnd then justEXPORT(mydeclspec, int, int);class mydeclspec whatever{    // boring...    stl::map<int, int> //example...}But I had some problems when I did the same thing in another DLL that had a similar definition of the map. It caused linker errors. as described in this article http://www.unknownroad.com/rtfm/VisualStudio/warningC4251.html   