warning C4275: non dll-interface class

[GoogleCodeExporter]

When I am statically linking the template library into my library, it always 
gives the warning:
 warning C4275: non dll-interface class 'std::_Container_base_secure' used as base for dll-interface class 'std::_Container_base_aux_alloc_empty<_Alloc>'

d:\program files\microsoft visual studio 9.0\vc\include\vector(439) : warning 
C4275: non dll-interface class 'std::_Container_base_secure' used as base for 
dll-interface class 'std::_Container_base_aux_alloc_empty<_Alloc>'
        with
        [
            _Alloc=std::allocator<std::string>
        ]
        d:\program files\microsoft visual studio 9.0\vc\include\xutility(93) : see declaration of 'std::_Container_base_secure'
        e:\ciscosoft\stb_studio\studio_tool\branches\srcgen\ctemplate\windows\ctemplate\template_cache.h(60) : see reference to class template instantiation 'std::vector<_Ty>' being compiled
        with
        [
            _Ty=std::string
        ]
e:\ciscosoft\stb_studio\studio_tool\branches\srcgen\ctemplate\windows\ctemplate\
template.h(382) : warning C4251: 'ctemplate::Template::original_filename_' : 
class 'std::basic_string<_Elem,_Traits,_Ax>' needs to have dll-interface to be 
used by clients of class 'ctemplate::Template'
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]
e:\ciscosoft\stb_studio\studio_tool\branches\srcgen\ctemplate\windows\ctemplate\
template.h(384) : warning C4251: 'ctemplate::Template::resolved_filename_' : 
class 'std::basic_string<_Elem,_Traits,_Ax>' needs to have dll-interface to be 
used by clients of class 'ctemplate::Template'
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]


how to solve this problem ?
Thank you.

Original issue reported on code.google.com by [email protected] on 29 Dec 2010 at 3:46

[GoogleCodeExporter]

Sorry for the tardy reply; for some reason I didn't get any mail when this 
issue was filed, so I just saw it now.

I don't know anything about static linking, and only the bare minimum about dll 
interfaces (the less I know, the happier I am ;-) ).  I imagine I'm doing a 
dllexport() or something, when I shouldn't be because it's a static library?  
How are you making the static lib?

If you can figure out a fix for this, I'm happy to put it in the next release.  
However, I'm making a new release today (which is how I happened to notice this 
issue finally), so it will be a little while before the next one.

Original comment by [email protected] on 25 Jan 2011 at 12:22

• Added labels: Type-Defect, Priority-Medium

[GoogleCodeExporter]

It's been a while and I haven't heard any more from this.  I'm going to close 
the bug.  Feel free to reopen if you have more information.

Original comment by [email protected] on 26 Aug 2011 at 1:30

• Changed state: WontFix

[GoogleCodeExporter]

I think the problem is here?

http://code.google.com/p/google-ctemplate/source/browse/trunk/src/windows/ctempl
ate/template_cache.h

In this file, even when CTEMPLATE_DLL_DECL is defined to be empty, 
__declspec(dllexport) gets used.

Original comment by [email protected] on 16 Dec 2011 at 9:32

[GoogleCodeExporter]

Hmm, that's plausible.  I'm seeing more of these errors in the new release I'm 
preparing and would love to figure out how to suppress them (without having to 
understand any of it, since it seems like a rathole...)

What's the right fix here?  I guess we just do nothing if CTEMPLATE_DLL_DECL is 
defined but empty?  I'm afraid that's probably not possible via the 
preprocessor, though maybe it is.

Original comment by [email protected] on 17 Dec 2011 at 12:12

• Changed state: New

[GoogleCodeExporter]

Please see my comment on issue 85:
http://code.google.com/p/ctemplate/issues/detail?id=85#c10

Original comment by [email protected] on 4 Jun 2012 at 5:19

[GoogleCodeExporter]

Compiling v2.2 with visual studio 2012 I have encountered the same warning: 
1>D:\Projects\ctemplate-2.2\src\ctemplate/template.h(388): warning C4251: 
'ctemplate::Template::resolved_filename_' : class 
'std::basic_string<_Elem,_Traits,_Alloc>' needs to have dll-interface to be 
used by clients of class 'ctemplate::Template'
1>          with
1>          [
1>              _Elem=char,
1>              _Traits=std::char_traits<char>,
1>              _Alloc=std::allocator<char>
1>          ]

The following code in template.h fixed it:

template class __declspec(dllexport) std::basic_string<char, 
                                                       std::char_traits<char>, 
                                                       std::allocator<char> >;

Original comment by [email protected] on 11 Aug 2013 at 9:37

Attachments:

• template.h.patch