Combining GPL and non-GPL code
andrew.wilson at intel.com
Thu Aug 2 18:15:30 UTC 2007
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.
> 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
> 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
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
the original code is also intact. If the code does contain any
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
chain under GPL.
Intel open source technology center
More information about the License-discuss