Subject: Re: LGPL... variations on a theme
From: Bernard Lang <Bernard.Lang@inria.fr>
Date: Fri, 6 Jul 2001 10:51:34 +0200

On Thu, Jul 05, 2001 at 11:05:34AM -0700, Ian Lance Taylor wrote:
> Bernard Lang <Bernard.Lang@inria.fr> writes:
> 
> > On Wed, Jul 04, 2001 at 11:31:56PM -0700, Ian Lance Taylor wrote:
> > > Bernard Lang <Bernard.Lang@inria.fr> writes:
> > > 
> > > > 2- Another organization is producing a free compiler, and an associated
> > > > run-time library. The run-time library is LGPLed.
> > > >    They are concerned that potential users will not like the
> > > > constraint of the LGPL on "work that uses the Library" as described in
> > > > section 6 of the LGPL, namely that one must provide a relinkable
> > > > version of the program (so as to allow free modification of the
> > > > library components used).
> > > >    The problem is not so much that people do not want to give that
> > > > freedom, but that the hassle of being contrained to do it for ever may
> > > > discourage potential users at the onset of their project.
> > > >    So the idea is to remove that constraint (possibly while
> > > > encouraging people to do it anyway).
> > > >    The idea is that a free system that is a bit more lax on GPLing is
> > > > better than a dead system (they want, need their system to live).
> > > >    I am not too keen on this, but I would welcome comments.
> > > 
> > > If you remove that constraint, then they can pretty much do anything.
> > > They can modify the library, add all sorts of proprietary goop, and
> > > then release a fully linked program without providing the source to
> > > the modified library.  I'm not sure how this is different from the
> > > libgcc exception license, which is the GPL plus this paragraph:
> > > 
> > >     In addition to the permissions in the GNU General Public License, the
> > >     Free Software Foundation gives you unlimited permission to link the
> > >     compiled version of this file into combinations with other programs,
> > >     and to distribute those combinations without any restriction coming
> > >     from the use of this file.  (The General Public License restrictions
> > >     do apply in other respects; for example, they cover modification of
> > >     the file, and distribution when not linked into a combine
> > >     executable.)
> > 
> > Sorry, misunderstanding
> > 
> > The only constraint I consider for removal is the obligation to
> > provide relinkable object code for the "work that uses the Library".
> > 
> > The constraint to release source code for everything in LGPL would of
> > course stay.
> 
> Sorry, my misunderstanding.  They can modify the library, and release
> an executable linked against the modified library, but they still have
> to provide the sources to the modified library.  It doesn't help the
> person with the executable, but it may help improve the library for
> others.  This prohibits a proprietary fork, but it does permit people
> to ship proprietary executables which use the library.  Off the top of
> my head I can't think of another license like that.
> 
> Compare this to the libgcc license (the GPL with exception I mention
> above).  The libgcc license prohibits using a modified version of the
> library in a fully linked executable without sources.  It does permit
> using the unmodified library in a fully linked executable without
> sources.

I do not understand ... it looks to me that a modified version of the
library will inherit the libgcc exception, and be linkable as well.

isn't the libgcc exception license more liberal than the LGPL ?

and close to what I have in mind ?

I must have missed a point ....

> I guess my question would be: what is the goal?  Do they want code
> contributions?  Or do they just want their code to be out there?  If
> they want contributions, the LGPL plus exception might be better than
> the GPL plus exception.

The goal is: make the code free, protect the freedom, and minimize the
hassle for developers that use it (i.e. not constrain them with an
obligation to prepare and preserve a linkable version of the
proprietary parts) so that it will not deter them from chosing this
compiler.

They like to have code contributions. Part of the library was created
that way.

> Is it possible for them to release the library as a shared library?
> That would let them use the unmodified LGPL.

apparently that is not easy (but I have no idea why ... it came to my
mind, but I forgot to ask).

Thanks for this help.  I did not know of the libgcc exception license
(which surprises me, considering the time I spent reading on these
issues).
   Is it much used ?

Bernard

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