[Gcl-devel] Re: GCL compliance with GNU GPL

[Sam Steingold]

Hi Camm, thanks for your reply.

> * In message <address@hidden>
> * On the subject of "Re: GCL compliance with GNU GPL"
> * Sent on 30 Jun 2003 17:57:09 -0400
> * Honorable Camm Maguire <address@hidden> writes:
>
> Readline is a compile time gcl option.  I do agree that linking it in
> changes the license.  It does seem that a note in the COPYING file to
> this effect might be the most appropriate -- i.e. if you compile with
> readline, the product is GPL.  This gives users the opportunity to
> compile an lgpl version without readline should they desire.

Did you read the e-mail exchange between RMS and Bruno Haible about
readline and CLISP?  The link is here:
<http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/*checkout*/clisp/clisp/doc/Why-CLISP-is-under-GPL?rev=HEAD>.

for the terminally lazy, the upshot is that the mere possibility of
linking with readline means GPL for the whole product.
CLISP does come with a "noreadline" library and it can also be linked
without readline; CLISP does not use readline on win32 and amiga.
Nevertheless it is covered by GNU GPL because it _can_ be linked with
readline.  _This is the intent of the GNU GPL_.

The expression "compile an lgpl version" does not make sense to me.

> Personally, I'd be just as happy having the whole product be GPL, but
> I understand there are some users of GCL who want to build non-GPL
> enduser images.

I don't think this issue is up to you or your users.
Unless FSF, which holds the (c) to readline, gives GCL a special
dispensation to be distributed under the LGPL, you cannot do that.
When/if they do, you must mention that on GCL's web page an COPYING
file so that there will be no confusion in the future.

As for the users who want to build proprietary software with GCL, you
can add a clause to GCL's COPYING file, similar to the one in the CLISP
distribution:
<http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/*checkout*/clisp/clisp/COPYRIGHT?rev=HEAD>.

  This copyright does *not* cover user programs that run in CLISP and
  third-party packages not part of CLISP, if they only reference external
  symbols in CLISP's public packages (namely the packages COMMON-LISP,
  COMMON-LISP-USER, KEYWORD, EXT), i.e. if they don't rely on CLISP
  internals and would as well run in any other Common Lisp implementation.
  Such user programs are not covered by the term "derived work" used in
  the GNU GPL. Neither is their compiled code, i.e. the result of compiling
  them by use of the function COMPILE-FILE. We refer to such user programs
  as "independent work".

  You may copy and distribute memory image files generated by the
  function SAVEINITMEM, if it was generated only from CLISP and independent
  work, and provided that you accompany them, in the sense of section 3
  of the GNU GPL, with the source code of CLISP - precisely the same CLISP
  version that was used to build the memory image -, the source or compiled
  code of the user programs needed to rebuild the memory image (source
  code for all the parts that are not independent work, see above), and
  a precise description how to rebuild the memory image from these.


The bottom line is: the current situation is illegal and creates a
dangerous precedent.

IANAL.

PS. please keep the CC list intact, at least
<address@hidden> and <address@hidden> must receive this.

-- 
Sam Steingold (http://www.podval.org/~sds) running w2k
<http://www.camera.org> <http://www.iris.org.il> <http://www.memri.org/>
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Lisp: Serious empowerment.