Re: [Bug-gnulib] missing licenses in gnulib / m4

[Bruno Haible]

Paul Eggert wrote:
> > For the m4 files, I propose to add the standard notice to them:
> >
> > dnl Copyright (C) YEARS Free Software Foundation, Inc.
> > dnl This file is free software, distributed under the terms of the GNU
> > dnl General Public License.  As a special exception to the GNU General
> > dnl Public License, this file may be distributed as part of a program
> > dnl that contains a configuration script generated by Autoconf, under
> > dnl the same distribution terms as the rest of that program.
>
> For GPL'ed modules, I'd rather just use the GPL, as it's simpler and
> clearer.  I don't see the point of having a special exception for the
> m4 files if the underlying code is GPLed.
>
> For LGPL'ed modules the situation is a bit murkier, and the above
> notice would be fine with me.

Some m4 files are shared between GPLed and LGPLed packages, and it is
frequent to copy m4 macros from one file to another (much more frequent
than copying source code between .c files). For this reason, I think
it would be best if all *.m4 files have the same copying conditions.

The purpose of the "special exception" clause is so that also non-GPLed
packages can use autoconfiguration. We want to encourage the use of
configure scripts and of portable programs.

I see this "special exception" clause mostly as a clarification: Since
*.m4 files are never linked into executables or libraries, they could
also be used in non-LGPLed packages. But if the license doesn't explicitly
say so, the authors of such packages will be afraid to use it.

Bruno