On 9/23/07, William Stein <[EMAIL PROTECTED]> wrote: > > On 9/23/07, Jason Martin <[EMAIL PROTECTED]> wrote: > > Some thoughts: > > > > 1. I've been doing some performance comparisons on GMP 4.2.2 with the > > patches that Sage uses, and I haven't seen any remarkable differences > > between 4.2.2 and 4.2.1. Granted, I have only tested Linux on > > AMD64/Intel64 and OS X on Intel64. Perhaps some other platforms have > > a greater difference. (By the way, the GPL patches for gcd/xgcd seem > > to work just fine.) > > Is GMP-4.2.1 with the gcd/xgcd patch vastly faster than GMP-4.2.2 at > what the gcd patch is for (i.e., gcd's of million digit numbers)? > > > It is nice that it will compile under OS X now without patching... and > > it even builds dynamic libraries. It is somewhat slow without > > patches, though. > > Do you mean that GMP-4.2.2 is somewhat slow without patches? > Or that GMP-4.2.1 is? Or? > > > 2. I suspect that the GMP developers were very deliberate in their > > license choice and will not release it under "LGPLv2 or greater". > > Much of the v2/3 license debate hinges on DRM issues: public key > > crypto is a big part of most DRM systems, and GMP is a natural choice > > for implementing public key crypto... but it can't hurt to ask. > > I think GMP is not going to change to LGPLv2 or greater; switching > from LGPLv2 or greater to LGPLv3 is the one and only new "big feature" > of GMP 4.2.2 (see the release notes). > > Also -- much more importantly, the copyright owners of GMP > are the Free Software Foundation -- not "the GMP developers", > and their agenda is very clear. > > > 3. How much of Sage is under "v2 Only"? That's the only portion that > > should cause problems isn't it? > > Good question. First, how do we determine if something is v2 only? > From the GPL itself: "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." > > So the only problem would be software that specifically says "GPL > version *2*". For the Sage source code itself, we always just write > > > # Distributed under the terms of the GNU General Public License (GPL) > > except in the following files: > > interfaces/matlab.py: > matrix/matrix.pyx: > matrix/matrix0.pyx: > matrix/matrix1.pyx: > matrix/matrix2.pyx: > matrix/strassen.pyx: > > I hold the copyright on all those files above. > > However, in the COPYING file for Sage itself, I wrote: "All original > SAGE code is distributed under the terms of the GNU General Public > License *Version 2*." > > Just out of curiosity, would anybody be angry if I were to remove the > words "*Version 2*" from the above sentence in the COPYING file? > Evidently nobody (but me) has ever actually submitted any code to Sage where > they explicitly put "Version 2" in their copyright statement. > I'm asking this mainly to see what our options are.
A legal question: If I write SAGE code (ie, Python code which requires SAGE's data extra data structures), doesn't that force, by the nature of the GPL, my code to be GPL'd, whether it is included in SAGE or not? > > Regarding Sage dependencies: > > * PARI -- they include the GPLv2 in the distribution, but the source code > files all just say: "you can redistribute it and/or modify it under the > terms of the GNU General Public License", i.e., nothing about V2. > So evidently PARI isn't a problem. > > * Singular -- same as SAGE -- all source files say "GPL version 2 or > latter" or don't > mention anything about versions. The top-level copying file does very > explicitly say "( version 2 of the License );" > > * clisp -- a cursory glance and it seems the same as Sage and Singular -- > the top level COPYRIGHT file explicitly says GPL v2, but when you look > at sources, if they have a copyright statement it (here I didn't check > everything) says "v2 or later". > > I'm not checking anymore right now, since perhaps the above is enough > of a sample to spark some useful discussion. > > > 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/ -~----------~----~----~----~------~----~------~--~---
