Re: Microsoft's Linux Kernel Code Drop Result of GPL Violation

[Florian Weimer]

* Hyman Rosen:

> Florian Weimer wrote:
>> Apparently, it is unclear that linking GPLed code with proprietary
>> code results in a GPL violation---if the combination is not used to
>> restrict use of the combined work (i.e., you still can run and copy it
>> freely).
>
> I think it's clear if static linking is involved, but others
> may disagree (especially here :-)

I used to think it was clear, but there's this curious lack of
enforcement, so I've got doubts.

>> I haven't checked recently, but I think Microsoft still does
>> this with its GCC distribution in Windows Services For UNIX: GCC is
>> linked against a proprietary libc, and this libc accompanies the
>> executable (so the system library exception cannot be used).
>
> What do you mean? What does accompanying the executable have
> to do with the system library exception? I don't think you
> understand the system library exception correctly. It allows
> GPLed programs to be linked against non-free libraries which
> are part of an operating system or major component thereof.

Unless the component accompanies the executable.

It's true that I don't understand the sytem library exception in
version 3 of the GPL.  The condition, "included in the normal form of
packaging a Major Component, but which is not part of that Major
Component", doesn't make much sense to me.  How can be something which
is normally included with something not be considered part of
something else?

> So you can link with non-free libc libraries, Apple GUIs,
> and so forth - things necessary for a program to be able to
> run on such a system. It's a compromise to the free software
> paradigm, trading some freedom for the ability to work on
> non-free platforms.

Interix (Microsoft?) GCC does not link directly against Windows
run-time libraries, but against a proprietary Interix libc, which
comes with Interix GCC.

This not really different from GPLed programs linking QPL libraries
(like KDE did several years ago) or BSD-with-advertising-clause
libraries (OpenSSL still haunts us today), or GPLv3 libraries (if the
program is GPLv2; there's quite a bit of trouble coming up in this
area).