Combining GPL and non-GPL code

[Wilson, Andrew]

David Woolley wrote:

> Roger Fujii wrote:
>
>> You are missing the mechanics of how licenses work.  These things
>> are all source/receiver based - that is, the last person in the
>
> That conflicts with a basic concept in the GPL, the "public".  The 
> concept is that indirect recipients also receive a valid licence.
There 
> may be belt and braces wording, but, basically the theory is that the 
> GPL is a bare licence, not a contract, so doesn't require offer and 
> acceptance at each step.
>
> I don't think the FSF would intend that other bare licences for parts
of 
> GPLed code should not be "public".

... and then this thread went off into the weeds on the ever-popular
argument over whether GPL is a license or a contract without addressing
Roger's basic point.  To wit, following the chain of licensing for a
derivative
work which contains non-GPL and GPL code inevitably leads to a scenario
where a user only has a license under GPL.  For illustrative purposes,
let's look at a chain

BSD -> GPL+BSD -> GPL -> end user

Roger's argument, with which I complete concur, is that the end user
who has received a copy from a distributor under GPL does not
have sufficient rights to strip off GPL and revert to the original
BSD.  Arguments which say it is ever valid to strip off GPL from
a derivative, under any circumstances,
will no doubt encounter stiff counter-arguments from GPL advocates.

>From a pragmatic point of view, although GPL requires you to mark source
code changes, in the real world this doesn't always happen.  The user
who has received a copy of a derivative should see the original
BSD copyrights intact in the sources, but he/she is probably ill-advised
to assume
the original code is also intact.  If the code does contain any
modifications,
if those modifications are made to a GPL'd derivative they
are automatically GPL.  If this user really wants the original
BSD code under a BSD license then he/she would be well advised, IMO,
to find a pristine original copy which has not passed through a
distribution
chain under GPL.

Andy Wilson
Intel open source technology center