Re: Licence questions

[Detlef Vollmann]

Paul Eggert wrote:
> The rationale was the usual one for free software: we want to make
> sure that works derived from lalr1.cc remain free.
The question is what you consider as "derived work".
AFAICS, GNU software that produces other software don't consider
this produced software as "derived" work.


> You'd need to make a strong case that lalr1.cc be distributed under
> other-than-GPL terms.  GPL is the default with GNU software.
Sorry, probably my first posting was mis-understandable.
I have absolutely no problems keeping lalr1.cc itself under GPL.
And any other skeletons I might derive from that would also
be under GPL.

But the code produced by bison (which of course contains a
substantial part of the chosen skeleton) should not be restricted
by the licence of bison itself (and its skeletons).
This is the typical approach of other GNU software that generates
software, e.g. GCC, autoconf, automake, flex, bison (earlier versions
or using yacc.c as skeleton).
All those programs produce source code (GCC produces assembler code)
that contain substantial parts of verbatim copied skeletons,
but nevertheless don't restrict that produced source code by
GPL.  E.g. configure scripts produced by autoconf include the
following note:

# Copyright 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002
# Free Software Foundation, Inc.
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.

I think something similar should be in the source code produced
by bison.

A similar case is glibc, where substantial amounts of code in
final executables comes directly out of glibc, but still LGPL
doesn't put any (L)GPL restrictions on linked executables.
Unfortunately, as LGPL's wording is very specific to libraries
and builds on the difference between binary code and source code,
LGPL isn't an appropriate option for lalr1.cc.

> Out of curiosity, what sort of environment is that?  Even the BSD
> distributions ship GNU software.  Perhaps you can arrange for an
> exception in your environment, just as the BSD distributions do.
The environment is Boost (www.boost.org) and as I believe
that their licence requirements for submissions are reasonable
I'm not going to ask for an exception.

If you insist to restrict software produced by bison through
lalr1.cc and skeletons derived from that, I'll derive my
skeleton from yacc.c.  And if you think that then the produced
software is still restricted by GPL, I'm going to produce a patch
to BSD yacc.
Both of these wouldn't be hard work, it would just be annoying.

Detlef

-- 
Detlef Vollmann   vollmann engineering gmbh
Linux and C++ for Embedded Systems    http://www.vollmann.ch/