Re: License of that GNAT patch ?

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

Georg Bauhaus wrote on comp.lang.ada:
>> No.  If you receive a file under the GPLv3 with Runtime Library
>> Exception, you may:
>>
>> - incorporate this file into proprietary software and distribute that
>> - redistribute the file with unchanged license
>> - redistribute the file under pure GPLv3
>>
>> at your choice.
>
> My question was referring to a changed library, in this case a patched
> library. The library would, therefore, not just be incorporated, but
> would be changed. Only then is this different library to be incorporated.

I thought this was clear for anyone who has been near GNAT or GCC.
This case is foreseen and allowed in the GPLv3 with Runtime Library
Exception.

>> Correct.  In this scenario, the license of the file is GMGPL all along,
>> permitting inclusion into proprietary software.  What is your point?
>
> The point is changing software that is licensed under GPLv3 with
> exception.

This is allowed.  The whole point of free software is that people can
change it.  I still don't understand what you are driving at.

> Neither the GMGPL (its exception) nor the GCC Runtime Library Exception,
> unlike the Java classpath exception, say something about making changes
> to the software they cover. The exception of the GMGPL is about instances
> and linking. The GCC Runtime Library Exception is about target code that
> GCC produces from its own library and independent modules.
> It does not itself say something about changing the library.
> (And then doing things mentioned above.)

I think you need to re-read the GPLv3...

> Consider a library that is based on the GCC runtime library
> by being a (sufficiently) patched version thereof.
>
> When does patching imply "based on"?

When the patch refers to copyrighted material.

> Who has the right to say how to use this new, patched library?

The owner of the copyright of the original work.

> What if there is no assignment of copyright to settle ownership
> of this new work?

In this case, the copyright on the derivative work belongs to all
contributors and you enter license hell as Linux illustrates.

The FSF requires copyright assignment precisely to avoid this license
hell.

> If this isn't a a legal issue, wow, then I imagine that any Ada shop
> can take whatever they need from the whole of the FSF Ada body,
> modify it in whichever way they like,

Yes

> and distribute binaries
> made from the result, without any obligation regarding sources.

This is true only of the subset of the Ada sources that are covered by
the GPLv3 with Runtime Library Exception.  The compiler is covered by
the pure GPL.

> (They have been patching sources to which a linking exception applies...
> I can't help but think that a linking permission does not imply
> more far reaching permissions.)
> Sounds like a general presumption in the sense of weakening copyleft,

Are you trying to say that the Runtime Library Exception weakens the
GPL?  Of course it does, and this is the whole point of the Runtime
Library Exception, and that's why it is called an Exception!  But the
political reason for weakening the GPL is not to encourage
freeloaders, but to encourage the switch from proprietary compilers
and runtime libraries to free ones, even if the software built on top
of the runtime library is proprietary.

--
Ludovic Brenta.