[sigc] libsigc++, LPGL and c++ templates

[klaus triendl <triendl kj aon at>]

Hello,

I know libsigc++ already some years and I use it in an open source project.
Now, I'd like to use it in my company, too - we make a proprietary 
software application on windows platforms.

There are long discussions in newsgroups about the LGPL and c++ 
templates and I must admit that can't figure it out.

Some people think that templates are just "header files" not falling 
under LGPL because the license addresses object code only, some think 
that changes in the library only concern the library but not the 
executable program and others think that template instantiations cause 
object code from the library to be incorporated in the executable 
program, thus rendering it a derivative work of the library.

I understand that if e.g. the slot implementation is changed then the 
object code of the libsigc++ library is changed and the user could 
exchange the shared library with his/her own version.
But it's not clear regarding template instantiations and derived 
template classes (e.g. classes derived from sigc::adapts).


Could you give me a clear understanding what I can do with libsigc++ and 
what I must not?
Is it enough to link my executable dynamically and distribute the 
executable alone with the sigc-2.0.dll or am I required to provide 
object/source code in case somebody changes templates concerning e.g. 
functors?


Thank you for enlightening me,

--
Klaus Triendl