Compiling programs licensed under the GPL version 2 with GCC 4.4

Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

Kalle Olavi Niemitalo discovered that as an operating system vendor,
you are not allowed to distribute GPL version 2 programs if they are
compiled with GCC 4.4.  The run-time library is GPL version 3 or
later, which is incompatible with GPL version 2, so it is not
permitted to link this with the GPLv2-only program and distribute the
result.  (Previous discussions have centered on infringing GCC's
license, so this is different.)  An operating system vendor cannot
make use of the system library exception in the GPL version 2; this
part is quite similar to the OpenSSL and former Qt situation.

According to Kalle, this is [gnu.org #433709] at the FSF.

What shall we do about it?  Any solution without support from the FSF
will result in circumventing the restrictions imposed by the new GCC
library exception.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Joe Buck]

On Sat, Jul 25, 2009 at 01:53:40PM -0700, Florian Weimer wrote:
> Kalle Olavi Niemitalo discovered that as an operating system vendor,
> you are not allowed to distribute GPL version 2 programs if they are
> compiled with GCC 4.4.  The run-time library is GPL version 3 or
> later, which is incompatible with GPL version 2, so it is not
> permitted to link this with the GPLv2-only program and distribute the
> result. 

That's incorrect.  The runtime library is GPLv3 or later, but with an
*exception* that permits linking not only with GPLv2 programs, but
also with proprietary programs.

The relevant document is the GCC Runtime Library Exception.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

* Joe Buck:

> On Sat, Jul 25, 2009 at 01:53:40PM -0700, Florian Weimer wrote:
>> Kalle Olavi Niemitalo discovered that as an operating system vendor,
>> you are not allowed to distribute GPL version 2 programs if they are
>> compiled with GCC 4.4.  The run-time library is GPL version 3 or
>> later, which is incompatible with GPL version 2, so it is not
>> permitted to link this with the GPLv2-only program and distribute the
>> result. 
>
> That's incorrect.  The runtime library is GPLv3 or later, but with an
> *exception* that permits linking not only with GPLv2 programs, but
> also with proprietary programs.

Eh, this exception doesn't change that the GPLv2 program perceives the
GPLv3 as incompatible.  Why would it?

I can't take my own proprietary library, give permission to link it
with GPLv2 programs, link it with a GPLv2 program, and distribute the
result.  The GPLv2 license on the program does not permit this.  And
as far as the GPLv2 is concerned, the GPLv3 is like a proprietary
license because it has got additional restrictions.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Vincent Lefevre]

On 2009-07-25 18:57:25 -0700, Joe Buck wrote:
> That's incorrect.  The runtime library is GPLv3 or later, but with an
> *exception* that permits linking not only with GPLv2 programs, but
> also with proprietary programs.

If the runtime library is GPLv3 or later, shouldn't programs linked
with it state that and be distributed with a copy of this licence?
I think I've never seen this (except for programs that are themselves
GPLv3 or later).

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.org/blog/>
Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Arnaud Charlet]

> Eh, this exception doesn't change that the GPLv2 program perceives the
> GPLv3 as incompatible.  Why would it?

Is it GPLv2 or GPLv2+? If the latter (the license includes something like
"either version 2 of the License, or (at your option) any later version"),
then nothing prevents you from distributing the program under GPLv3+ instead
of GPLv2+.

Arno

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

* Arnaud Charlet:

>> Eh, this exception doesn't change that the GPLv2 program perceives the
>> GPLv3 as incompatible.  Why would it?
>
> Is it GPLv2 or GPLv2+?

GPLv2 (I tried to stress by writing "GPLv2-only").

> If the latter (the license includes something like "either version 2
> of the License, or (at your option) any later version"), then
> nothing prevents you from distributing the program under GPLv3+
> instead of GPLv2+.

Right, but we've got some stuff which is GPLv2-only, such as Git,
OpenOffice, OpenJDK, etc.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Arnaud Charlet]

> GPLv2 (I tried to stress by writing "GPLv2-only").

Understood.

> > If the latter (the license includes something like "either version 2
> > of the License, or (at your option) any later version"), then
> > nothing prevents you from distributing the program under GPLv3+
> > instead of GPLv2+.
> 
> Right, but we've got some stuff which is GPLv2-only, such as Git,
> OpenOffice, OpenJDK, etc.

I guess you should check with FSF lawyers in this case.

I suspect that other clauses would apply. For example, assuming that the GCC 4.4
run-time is part of the OS (which is likely the case you described as far as I
understand), then the GPLv2 OS exception clause would apply.

But of course, I'm not a lawyer, so the best advice is to check with FSF
directly, since this list is not the right media for it.

Arno

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

* Arnaud Charlet:

>> > If the latter (the license includes something like "either version 2
>> > of the License, or (at your option) any later version"), then
>> > nothing prevents you from distributing the program under GPLv3+
>> > instead of GPLv2+.
>> 
>> Right, but we've got some stuff which is GPLv2-only, such as Git,
>> OpenOffice, OpenJDK, etc.
>
> I guess you should check with FSF lawyers in this case.

Kalle already did that, back in April, and hasn't received any reply.
I haven't received any reply for my request about QPL compilers like
Objective Caml, either.

I would rather ask a lawyer of my own, but this doesn't solve the
issue that we generally want to follow the FSF's wishes and not
stretch things as far as possible under copyright law.

> I suspect that other clauses would apply. For example, assuming that
> the GCC 4.4 run-time is part of the OS (which is likely the case you
> described as far as I understand), then the GPLv2 OS exception
> clause would apply.

It doesn't for someone who ships a complete operating system.  Here's
the relevant quote from the GPL, version 2:

| However, as a special exception, the source code distributed need
| not include anything that is normally distributed (in either source
| or binary form) with the major components (compiler, kernel, and so
| on) of the operating system on which the executable runs, unless
| that component itself accompanies the executable.

The FSF claims that it is not permitted to link against arbitrary
libraries when you distribute a program is part of an operating
system.  Free software vendors receive advice according these lines,
and the GPL FAQ at <http://www.gnu.org/philosophy/license-list.html>
also reflects that.  For instance, it says about the QPL:

| Since the QPL is incompatible with the GNU GPL, you cannot take a
| GPL-covered program and QPL-covered program and link them together,
| no matter how.

This still haunts us today with OpenSSL, which is licensed under a
BSD-style license with an advertizing.  It's one reason why we stick
with FSF GNAT in Debian, the GPLed run-time library in AdaCore's
distribution would cause too many licensing headaches.

On the other hand, there is a curious lack of enforcement.  Most
proprietary operating system vendors (including Microsoft and Juniper,
apparently) get a free pass in this area.  They just link GPL-only GNU
software with their proprietary system libraries and ship the result,
often in the same download or on the same media.  This makes me feel
rather bitter.  Why do proprietary vendors receive this additional
freedom, but not free software vendors?

If the FSF keeps refusing to enter any discussion on this matter (I'm
not even talking about agreeing on a solution yet!), our options for
dealing with the GCC 4.4 relicensing fallout at Debian are pretty
limited.  It's also likely that any unilateral action will undermine
the effect of some of the FSF's licensing policies.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Joe Buck]

> * Joe Buck:
> 
On Sat, Jul 25, 2009 at 01:53:40PM -0700, Florian Weimer wrote:
> >> Kalle Olavi Niemitalo discovered that as an operating system vendor,
> >> you are not allowed to distribute GPL version 2 programs if they are
> >> compiled with GCC 4.4.  The run-time library is GPL version 3 or
> >> later, which is incompatible with GPL version 2, so it is not
> >> permitted to link this with the GPLv2-only program and distribute the
> >> result.

I wrote:
> > That's incorrect.  The runtime library is GPLv3 or later, but with an
> > *exception* that permits linking not only with GPLv2 programs, but
> > also with proprietary programs.

On Sat, Jul 25, 2009 at 11:46:51PM -0700, Florian Weimer wrote:
> Eh, this exception doesn't change that the GPLv2 program perceives the
> GPLv3 as incompatible.  Why would it?

Doesn't matter, because the runtime library is not under GPLv3.  It's
under GPLv3 plus the runtime restriction.  That combination is more
permissive than GPLv2 (because of the exceptions it makes).  Therefore,
as far as I can tell, there is no conflict; the combined program has
no restrictions beyond the GPLv2 restrictions.

In particular, the DRM rules don't apply; the more restrictive rules
on patents don't apply.  Unless you can identify a specific restriction
that isn't waived by the runtime exception license, then I don't see
the problem.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

* Joe Buck:

> Doesn't matter, because the runtime library is not under GPLv3.  It's
> under GPLv3 plus the runtime restriction.  That combination is more
> permissive than GPLv2 (because of the exceptions it makes).  Therefore,
> as far as I can tell, there is no conflict; the combined program has
> no restrictions beyond the GPLv2 restrictions.

I think it's unordered with respect to the GPLv2.

> In particular, the DRM rules don't apply; the more restrictive rules
> on patents don't apply.

But if I change the run-time library, I still have to license those
changes under the GPLv3 if I want to distribute them, right?  For the
library, all the additional GPLv3 restrictions apply if I modify it
(such as the patent licensing rules, or the fundamental weakening of
copyleft).  I think that traditionally, such restrictions, even if
concentrated to the code to which GPL software is linked, has been
enough to make the code incompatible with the GPL.  If this were not
the case, the Apache License 2.0 would have been deemed compatible
with the GPL version 2 because it explicitly mentions that its
requirements do not apply to code linked to the library.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Paolo Bonzini]

> But if I change the run-time library, I still have to license those
> changes under the GPLv3 if I want to distribute them, right?

Yes.  But if you change the runtime library and link something else with 
the modified runtime library, the "something else" does not fall 
automatically under the GPLv3, even if you distribute them together.

The runtime library must be accompanied by the preferred form for 
modification (source code), the "something else" can even be distributed 
as a binary.

Paolo

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

* Paolo Bonzini:

>> But if I change the run-time library, I still have to license those
>> changes under the GPLv3 if I want to distribute them, right?
>
> Yes.  But if you change the runtime library and link something else
> with the modified runtime library, the "something else" does not fall
> automatically under the GPLv3, even if you distribute them together.

Yes---but we've been told repeatedly over the years that you cannot
link GPLv2 programs with libraries under a GPLv2-incompatible license
and ship both on the same media, even if the library license is not
copyleft-like and does not prevent this.  (If this was possible, it
would be rather trivial to work around the copyleft character of the
GPLv2.)

> The runtime library must be accompanied by the preferred form for
> modification (source code), the "something else" can even be
> distributed as a binary.

It's not the run-time library license that's the problem here.  It's
the GPLv2-only program whose license appears to be infringed by
linking against the run-time library and distributing the combined
result.

Keep in mind that for a GPLv2-only program, the GPLv3 is like a
proprietary license (quite similar in effect to the Apache License
2.0, or the OpenSSL license, or the QPL, or the BSD license with the
advertising clause).

I wouldn't object if the FSF publicly declared that under their
interpretation of the GPLv2, the system library exception in the GPLv2
allows us to link against libraries shipped in a separate Debian
package, dynamically or statically.  We likely have that permission
under copyright anyway.  It's just against everything the FSF has told
us over the years, so I don't think it will happen.

(Legally, a placet from the FSF doesn't buy as anything, of course,
because individual copyright holders may not share the FSF
interpretation.  But it would be a signal nevertheless.)

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Alfred M. Szmidt]

Please take this up with legal@gnu.org.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Robert Dewar]

There is so much incorrect information in this thread that
I would not even try to start to fix it, since it would
just cause more confusion than is already there. I would
just remind people that

a) discussions of licensing issues are off topic on this mailing list

b) you should ignore all such discussions, since they invariablly
    include lots of legal-sounding opinions from people who are not
    lawyers and don't know, and often have significant misconceptions.

c) remember that even lawyers don't know what the exactly implications
    of copyright law are, juries often surprise. So even if you go ask
    a lawyer, you won't get a definitive opinion.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Paolo Bonzini]

> b) you should ignore all such discussions, since they invariablly
> include lots of legal-sounding opinions from people who are not
> lawyers and don't know, and often have significant misconceptions.

Indeed I'm not answering to Florian's latest message, because I'm not 
sure what he misunderstood of my message and I would probably give out 
wrong information.

But I don't see much misinformation in the replies so far (can't judge 
mine of course), unlike other recent licensing threads.

Paolo

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Manuel López-Ibáñez]

2009/7/27 Robert Dewar <dewar@adacore.com>:
> a) discussions of licensing issues are off topic on this mailing list
>
> b) you should ignore all such discussions, since they invariablly
>   include lots of legal-sounding opinions from people who are not
>   lawyers and don't know, and often have significant misconceptions.
>
> c) remember that even lawyers don't know what the exactly implications
>   of copyright law are, juries often surprise. So even if you go ask
>   a lawyer, you won't get a definitive opinion.

These three points could be included in a standard answer to licensing
questions posted to gcc@. Invariably, all such threads are a waste of
time and bandwidth. Perhaps we can include the standard answer in some
webpage so we can copy+paste or just point to it. A first attempt at:
http://gcc.gnu.org/wiki/Licensing

Cheers,

Manuel.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Dave Korn]

Robert Dewar wrote:

> b) you should ignore all such discussions, since they invariablly
>    include lots of legal-sounding opinions from people who are not
>    lawyers and don't know, and often have significant misconceptions.

  :) We have a name for that on the cygwin list:

      http://cygwin.com/acronyms/#YANALATEYHSMBSI

    cheers,
      DaveK

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Florian Weimer]

* Robert Dewar:

> b) you should ignore all such discussions, since they invariablly
>    include lots of legal-sounding opinions from people who are not
>    lawyers and don't know, and often have significant misconceptions.

This is not about legal issues.  It's about FSF policy.  If I wanted
legal advice, I'd ask a lawyer, and rely on that advice (to the extent
that is possible), even if it is at odds with what the FSF or the GCC
developers presumably want (like an effective copyleft for GCC with
modules).

It seems to me that the new GCC run-time library license has the side
effect of forcing GPLed software to upgrade to GPL version 3 to remain
redistributable in compiled form.  If this is not your intent (as GCC
developers), I think the Steering Committee should ask the FSF for
official clarification on this matter.  I'd also like to know what we
should do with the Objective Caml compiler in Debian, by the way.

My main issue is that I don't see how, under the same set of policies,
it can be acceptable to link a GPLv2 program to GPLv3 system libraries
covered by the GCC library exception, but it's not okay to link
another GPLv2 program to Apache-2.0-licensed system libraries.  Both
library licenses do not infect the program, and both licenses are
incompatible with the GPLv2 (according to the FSF).  Or am I nuts and
this mismatch does not exist?

The problem with "go ask the FSF" is that they don't react in a
reasonable time frame (beyond an auto-ack from their trouble ticket
system).

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Alfred M. Szmidt]

   > a) discussions of licensing issues are off topic on this mailing list
   >
   > b) you should ignore all such discussions, since they invariablly
   >   include lots of legal-sounding opinions from people who are not
   >   lawyers and don't know, and often have significant misconceptions.
   >
   > c) remember that even lawyers don't know what the exactly implications
   >   of copyright law are, juries often surprise. So even if you go ask
   >   a lawyer, you won't get a definitive opinion.

   These three points could be included in a standard answer to
   licensing questions posted to gcc@. Invariably, all such threads
   are a waste of time and bandwidth. Perhaps we can include the
   standard answer in some webpage so we can copy+paste or just point
   to it. A first attempt at: http://gcc.gnu.org/wiki/Licensing

The effort is laudable, but the above text has a negative sounding
tone.  It doesn't point users in the right direction.

How about the following wording,

  The most common questions and answers regarding the GNU GPL and how
  it applies can be found in the GNU GPL FAQ
  <http://gnu.org/licenses/gpl-faq.html>, if you cannot find the
  answer there please contact <legal@gnu.org> instead of posting your
  question on one of the GCC mailing-lists.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Robert Dewar]

Florian Weimer wrote:
> * Robert Dewar:
> 
>> b) you should ignore all such discussions, since they invariablly
>>    include lots of legal-sounding opinions from people who are not
>>    lawyers and don't know, and often have significant misconceptions.
> 
> This is not about legal issues.  It's about FSF policy.  If I wanted
> legal advice, I'd ask a lawyer, and rely on that advice (to the extent
> that is possible), even if it is at odds with what the FSF or the GCC
> developers presumably want (like an effective copyleft for GCC with
> modules).

Discussion of FSF policy on licensing issues is also off-topic for
this mailing list.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Robert Dewar]

Dave Korn wrote:
> Robert Dewar wrote:
> 
>> b) you should ignore all such discussions, since they invariablly
>>    include lots of legal-sounding opinions from people who are not
>>    lawyers and don't know, and often have significant misconceptions.
> 
>   :) We have a name for that on the cygwin list:
> 
>       http://cygwin.com/acronyms/#YANALATEYHSMBSI

I would only add that being a lawyer does not mean that everything
you say should be taken at face value :-)
> 
>     cheers,
>       DaveK

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Manuel López-Ibáñez]

2009/7/27 Alfred M. Szmidt <ams@gnu.org>:
>   These three points could be included in a standard answer to
>   licensing questions posted to gcc@. Invariably, all such threads
>   are a waste of time and bandwidth. Perhaps we can include the
>   standard answer in some webpage so we can copy+paste or just point
>   to it. A first attempt at: http://gcc.gnu.org/wiki/Licensing
>
> The effort is laudable, but the above text has a negative sounding
> tone.  It doesn't point users in the right direction.
>
> How about the following wording,
>

It is in the wiki precisely so people can freely modify/add/remove text.

Cheers,

Manuel.

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Frank Ch. Eigler]

Robert Dewar <dewar@adacore.com> writes:

> [...]
>>> b) you should ignore all such discussions, since they invariablly
>>>    include lots of legal-sounding opinions from people who are not
>>>    lawyers and don't know, and often have significant misconceptions.
>>
>> This is not about legal issues.  It's about FSF policy.  [...]

(Perhaps this was a poorly chosen summary sentence; Florian's next
paragraph more clearly asks the GCC developers' opinion:

# It seems to me that the new GCC run-time library license has the
# side effect of forcing GPLed software to upgrade to GPL version 3 to
# remain redistributable in compiled form.  If this is not your intent
# (as GCC developers), I think the Steering Committee should ask the
# FSF for official clarification on this matter.


> Discussion of FSF policy on licensing issues is also off-topic for
> this mailing list.

Perhaps, yet the libgcc exception licensing issues were quite
prominently discussed right here, and not too many months ago.
Florian's concern sounds linearly connected to that.  If this is as
trivial a matter as some people seem to hint, perhaps someone can
supply a link to a prior discussion for it.


- FChE

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Paolo Bonzini]

On 07/25/2009 10:53 PM, Florian Weimer wrote:
> The run-time library is GPL version 3 or
> later, which is incompatible with GPL version 2, so it is not
> permitted to link this with the GPLv2-only program and distribute the
> result.  (Previous discussions have centered on infringing GCC's
> license, so this is different.)

You should have said why here or at least further down in the thread. 
Instead you always used vague terms.

I now understand fully the issue because it was pointed out to me 
outside the ML in a much more complete way.  And it is definitely none 
of this list's business---which is why I'm not mentioning the real 
source of doubt in this message, either.

Paolo

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Russ Allbery]

fche@redhat.com (Frank Ch. Eigler) writes:
> Robert Dewar <dewar@adacore.com> writes:

>> Discussion of FSF policy on licensing issues is also off-topic for
>> this mailing list.

> Perhaps, yet the libgcc exception licensing issues were quite
> prominently discussed right here, and not too many months ago.
> Florian's concern sounds linearly connected to that.  If this is as
> trivial a matter as some people seem to hint, perhaps someone can supply
> a link to a prior discussion for it.

Furthermore, the people Robert is telling him to go ask are not replying
to their e-mail.  Given that, on-topic or not, I think it's hardly
surprising for the issue to come up here.  The most effective way to keep
it from coming up here would seem to be for them to start answering their
e-mail.

-- 
Russ Allbery (rra@stanford.edu)             <http://www.eyrie.org/~eagle/>

Re: Compiling programs licensed under the GPL version 2 with GCC 4.4

[Joe Buck]

On Mon, Jul 27, 2009 at 05:34:34PM -0700, Russ Allbery wrote:
> fche@redhat.com (Frank Ch. Eigler) writes:
> > Robert Dewar <dewar@adacore.com> writes:
> 
> >> Discussion of FSF policy on licensing issues is also off-topic for
> >> this mailing list.
> 
> > Perhaps, yet the libgcc exception licensing issues were quite
> > prominently discussed right here, and not too many months ago.
> > Florian's concern sounds linearly connected to that.  If this is as
> > trivial a matter as some people seem to hint, perhaps someone can supply
> > a link to a prior discussion for it.
> 
> Furthermore, the people Robert is telling him to go ask are not replying
> to their e-mail.  Given that, on-topic or not, I think it's hardly
> surprising for the issue to come up here.  The most effective way to keep
> it from coming up here would seem to be for them to start answering their
> e-mail.

I would suggest that affected distributors contact the SFLC for an opinion
and advice.  I think that they are in the best position to work both with
the FSF and with other free software distributors to determine if there
is a genuine problem, what the scope of it is, and make suggestions
for a resolution.  They've done work for many other free software projects
outside of the FSF.

Continued use of this list to discuss the matter isn't going to produce
any reliable conclusions or good results.