Problem with template classes in DLLs

Hi,

  Does anyone know how I can get rid of this warning:

warning C4275: non dll-interface class 'ntfNotificationServer<enum ivNOTIFY_TYPE>' used as base for dll-interface class 'imageView'

The problem that I'm having is that the base class is a template class defined in a separate header file with no linkage specification:

template <class T> class ntfNotificationServer {...}

And used as a base for a class exported by the dll:

class ivDLLEXPORT imageView : public CView, public ivNotificationServer
{...}

ivDLLEXPORT is just a macro used to control dllimport/dllexport for .h & .cpp files.

I get the same warning from CView, but I can get rid of this one by predeclaring it like so:

class __declspec(dllimport) CView;

Unfortunately, if I do this for the template class, I have problems with inconsistant linkage for the member functions.

Thanks for any help,
Jerry
jmarescaAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

nietodCommented:
You need to declate the base class (template class) as __declspec(dllexport).
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
nietodCommented:
Try

template <class T> class DllExport ntfNotificationServer {...}

class ivDLLEXPORT imageView : public CView, public
ivNotificationServer
{...}

I assume you are indicating what type that ntfNotificationServer shoudl be expanded for in ImageView.  Right?  If not that is a problem.
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
C++

From novice to tech pro — start learning today.