On 9/24/07, mabshoff <[EMAIL PROTECTED]> wrote: > On Sep 24, 1:30 pm, "David Joyner" <[EMAIL PROTECTED]> wrote: > > On 9/24/07, Jaap Spies <[EMAIL PROTECTED]> wrote: > > > Jason Martin wrote: > > > > My vote would be to change the sage license to "GPLv2 or later" and > > > > try to get the Singular developers to do likewise. Mainly because > > > > that is less work. > > > > > > Does changing Sage to "v2 or later" require Sage to adopted future GPL > > > > changes? My interpretation is that it simply gives users the option > > > > to re-distribute it according to later versions of the GPL. It > > > > doesn't obligate Sage to adopt those future changes, does it? > > > > If any file inside a project says GPL V2 only and the rest of the code > is licensed under a GPL V2 compatible license that in turn makes the > whole project if distributed in binary form GPL V2 only. That does not > apply to the sources! > So if you see any file like that in Singular, > pari, GAP or whatever let the developer/copyright holder know and ask > them nicely to change the license to the same license as the rest of > the project. > We should also make sure that all our modifications to [L]GPL [2|3], > BSD, MIT licensed code are clearly licensed and we should make an > effort to merge our patches upstream.
Agreed. > > > If it says 'GPLv2 or any later version' version 2 still applies! > > > > "GPLv2 or later" means "you may copy, modify, and > > redistribute the code using either license GPLv2 or > > GPLv3 (at your preference)". You can't > > use both at the same time since they are incompatible. > > Exactly, and this means: When releasing a Sage binary linked against > gmp 4.2.2 any source bits that are "GPL V2 or later" are in effect > covered under the GPL V3 only in that binary release, because any > [L]GPL V3 library forces the use of the compatible GPL V3 license. The > sources that are GPL V2 or later can still be used under GPL V2 and if > you choose to use gmp 4.2.1 and not any other [L]GPL V3 code the > resulting binary distribution is covered under GPL V2. Obviously the > other code that is BSD licensed retains its license. This is exactly right. > As was pointed out in the thread before performance wise it won't make > any difference with Jason's patches. The are various bug fixes that > make it worthwhile to switch to the new release (even though there are > no new features beside the license change) and one patch went in to > support gcc 4.3, but that that one was mine (even though the patch > that went in did it differently). So I would suggest to license Sage's > code under GPL V2 or V3 (if you are paranoid about the successor of > GPL V3), but one should consider that once a hypothetical GPL V4 rolls > around some of the authors of Sage code might no longer be around/lost > contact to the project. So GPL V2 or later covers that and as long as > say William's contributions only are covered under "GPL V2 or V3" > nobody could realistically "hijack" Sage under a hypothetically bad > GPL V4, if you are that paranoid ;). I'm not going to do a GPL v2 or v3 only license. That is too painful to contemplate, since it will mean in 10 years having the same sort of problem, but much much worse. -- William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
