Re: [gentoo-dev] Eigen and GPL-2 exception - is a new licence required?

[Marcus D. Hanwell]

On Saturday 12 May 2007 15:22:15 Carsten Lohrke wrote:
> On Samstag, 12. Mai 2007, Harald van Dijk wrote:
> > Do you need to accept the unmodified GPL-2 for software licensed under
> > the GPL-2 plus exception? No? Then GPL-2 does not belong in LICENSE,
> > unless in a || group.
>
> Of course you accept the GPL plus the added exception. Just because an
> exception exists, it does not become a completely different license.
>
This is a big part of the reason I was unsure. In this case it is the GPL 
licence with the exception to extend your ability to include it in other 
work. Talking to the author he has done this because the library is a pure 
template library and so linking exception makes no sense - there is nothing 
to link to.

I suspected that GPL-2 would probably be fine. This is far from an isolated 
case. Benoit (the author of Eigen) and Diego have pointed out to me that 
libstdc++ contains similarly licenced template code for the same reasons - 
the LGPL and the GPL with linking exception are meaningless in this case.

Personally I would just like to get Eigen included, but didn't want to 
unnecessarily clutter our licences directory further. If anything it would be 
nice to come up with a more generic solution than adding this particular 
license with exception. The exception serves to make this license more 
permissive - i.e. it can be compiled into other code much as LGPL allows 
libraries to be linked to.

I guess I could add it and we could fix the licence later if there is no clear 
consensus (or policy already in place).

Thanks,

Marcus