On 11/11/10 11:20 AM, Jeroen Demeyer wrote:
On 2010-11-11 11:53, Dr. David Kirkby wrote:
The license must be a GPL version v2+ compatible license.
Note that GPLv3 is NOT compaible with GPLv2! I quote from
http://www.gnu.org/licenses/license-list.html#GNUGPL
As I understand it, the bit of GPL2 that is relevant is this section:
"9. The Free Software Foundation may publish revised and/or new versions of the
General Public License from time to time. Such new versions will be similar in
spirit to the present version, but may differ in detail to address new problems
or concerns.
Each version is given a distinguishing version number. If the Program specifies
a version number of this License which applies to it and "any later version",
you have the option of following the terms and conditions either of that version
or of any later version published by the Free Software Foundation. If the
Program does not specify a version number of this License, you may choose any
version ever published by the Free Software Foundation. "
My interpretation of that is if:
* Says GPL 2
then's it incompatible. But if
* It says GPL 2 or any later version or
* It says GPL, but with no version specified, then it's OK to use it.
This really is a minefield.
Please note that GPLv3 is not compatible with GPLv2 by itself. However,
most software released under GPLv2 allows you to use the terms of later
versions of the GPL as well. When this is the case, you can use the code
under GPLv3 to make the desired combination.
So either
1) the requirement that spkgs have GPLv2+ compatible licences must be
removed
2) we release Sage under GPLv3+
3) we remove all GPLv3+ code from Sage
I don't like it either, but that's the way it is.
I don't think releasing Sage under GPLv3+ solves the problem either, as any code
which specifies it's GPL version 2, with no mention of the ability to use a
later version, would then be incompatible.
So that idea would solve some problems, but create others.
Removing GPLv3+ code would be a very bad idea, as quite literally most new code
released will be released under GPL3.
In fact, if you create an application with recent autoconf versions, it even
adds a file "COPYING" saying your code is GPL3 !! (You can of course change that
file, but the point is that most new code will be released under GPL3).
I'm not totally convinced the OpenSSL issue has been resolved either. The Cygwin
port makes it clear you must install the OpenSSL libraries.
Jeroen.
Dave
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