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'needs to have dll-interface' warning

Thu, 28 Jul 2005 10:42:05 -0800

Hi,
I need some help with dlls. It's my first time writting dlls and I have a minor problem.

#ifdef MYPROJ_EXPORTS
#define _myprojExport __declspec(dllexport)
#else
#define _myprojExport __declspec(dllimport)
#endif

class _myprojExport MyClass
{
...
protected:
	typedef std::list<std::string> StringList;
	StringList mylist;
};

As you can see on the above code I have MyClass which is a simple class that I export. When mylist member is missing everything is compiled smoothly, however when I have mylist member variable on the class I get the following warning from my compiler (VS .NET 7.1).

warning C4251: 'MyClass::mylist' : class 'std::list<_Ty>' needs to have dll-interface to be used by clients of class 'MyClass'
with
[
_Ty=std::string
]

How can I create a dll-interface for std::list? I don't have to export std::list the client will find its implementation in <list>. How should I declare mylist in order to get rid of these warnings?

Thanks in advance,
Themis

Re: 'needs to have dll-interface' warning

Thu, 28 Jul 2005 10:56:24 -0800

: Hi,
: I need some help with dlls. It's my first time writting dlls and I have a minor problem.
:
:

: #ifdef MYPROJ_EXPORTS
: #define _myprojExport __declspec(dllexport)
: #else
: #define _myprojExport __declspec(dllimport)
: #endif
: 
: class _myprojExport MyClass
: {
: ...
: protected:
: 	typedef std::list<std::string> StringList;
: 	StringList mylist;
: };
:

:
: As you can see on the above code I have MyClass which is a simple class that I export. When mylist member is missing everything is compiled smoothly, however when I have mylist member variable on the class I get the following warning from my compiler (VS .NET 7.1).
:
: warning C4251: 'MyClass::mylist' : class 'std::list<_Ty>' needs to have dll-interface to be used by clients of class 'MyClass'
: with
: [
: _Ty=std::string
: ]
:
: How can I create a dll-interface for std::list? I don't have to export std::list the client will find its implementation in <list>. How should I declare mylist in order to get rid of these warnings?
:
: Thanks in advance,
: Themis
:

templates can't be exported -- but I think you can safely ignore the error if the application program will not have access to the template object.

Re: 'needs to have dll-interface' warning

Fri, 29 Jul 2005 00:53:38 -0800

:
: templates can't be exported -- but I think you can safely ignore the error if the application program will not have access to the template object.
:
:

Isn't there any way to get rid of because it polutes my build log and task list.

Themis

Re: 'needs to have dll-interface' warning

Fri, 29 Jul 2005 03:50:13 -0800

: :
: : templates can't be exported -- but I think you can safely ignore the error if the application program will not have access to the template object.
: :
: :
:
: Isn't there any way to get rid of because it polutes my build log and task list.
:
: Themis
:

#pragma warning(disable: xxxx) // replace xxxx with warning number

Re: 'needs to have dll-interface' warning

Wed, 05 Oct 2011 17:59:48 -0800

do not export entire class. Export only the needed functions and data.