A little GPL riddle (was: GPL as an evaluation license)

[Oleg Goldshmidt]

On Mon, Apr 11, 2011 at 11:20 AM, Oleg Goldshmidt <pub at goldshmidt.org> wrote:
> On Mon, Apr 11, 2011 at 2:09 AM, Aviad Mandel <aviad.mandel at gmail.com> wrote:
>> On Mon, Apr 11, 2011 at 1:22 AM, Oleg Goldshmidt <pub at goldshmidt.org> wrote:
>>>
>>> Someone gave you, i.e., "conveyed", "distributed", that object code
>>> whose only purpose is to create the browser when linked to some GPLed
>>> code. Therefore this object code is derivative work of the GPL code.
>>> Therefore if it is not GPLed the aforementioned "someone" is in
>>> violation of GPL. A user of such a browser who wants to have a look at
>>> or modify the browser will have a petty good case.
>>>
>> Purpose? Where does the GPL say anything about purpose?
>
> GPL v2,.paragraph 2:
>
> "These requirements apply to the modified work as a whole. If
> identifiable sections of that work are not derived from the Program,
> and can be reasonably considered independent and separate works in
> themselves, then this License, and its terms, do not apply to those
> sections when you distribute them as separate works. But when you
> distribute the same sections as part of a whole which is a work based
> on the Program, the distribution of the whole must be on the terms of
> this License, whose permissions for other licensees extend to the
> entire whole, and thus to each and every part regardless of who wrote
> it."

And in GPL v3:

Preamble:

To “modify” a work means to copy from or adapt all or part of the work
in a fashion requiring copyright permission, other than the making of
an exact copy. The resulting work is called a “modified version” of
the earlier work or a work “based on” the earlier work.

A “covered work” means either the unmodified Program or a work based
on the Program.

Note the "adapt all or part of the work" language that is relevant to
what constitutes "covered work".

Now read Sections 5 and 6 of GPL v3 carefully. They are not
particularly easy to read, but you will discern that all parts of
covered work must be GPLed. Exceptions are also listed, e.g.,
"aggregation", "system libraries", etc. - defined in Section 1. Note
also the definition of "Corresponding Source" in Section 1.

I hope it resolves your confusion.

-- 
Oleg Goldshmidt | oleg at goldshmidt.org