GMP forked; Torbjorn Granlund: "blatant falsehoods and sinister insinuations"

William Stein wstein at
Thu May 29 20:52:03 CEST 2008

Torbjorn Granlund:
> The other publicly stated reasons are a mixture of
> blatant falsehoods and sinister insinuations.
> This fork exists for some very different reasons than those publicy
> stated.

I know why the fork exists, so I'll state publicly precisely
why the fork exists.  The issues below are not
blatant falsehood or sinister insinuations.

1. FACT: (L)GPLv3 cannot be used by some companies.  See below where
I discuss this issue at length.

2. FACT: The GMP project is not developer friendly. This is easy to
see by reading the GMP mailing lists.

3. FACT: The GMP project does not have a regular and
predictable release cycle. How many times has the GMP 5.0 release
been moved back -- it used to be "sometime in 2007", but now the
GMP site says "5.0 is planned to come out in a couple of years."

4. FACT: The working code repository of GMP is closed.  There is
no public svn, etc. repository so that anybody can look at the latest
version of the GMP code. See 2.

5. FACT: Some extremely capable developers do not want to contribute to
an LGPL'd project, because they don't want their voluntary contributions
to be used by Maple, Mathematica and Magma to make money.

6. FACT: The GMP project is unfriendly toward natively supporting
Microsoft Windows using MSVC.  Just see any email you have sent
to Brian Gladdman.

7. FACT: The GMP project has been unfriendly toward supporting OS X.
Just search the gmp list archives for OS X.

Torbjorn Granlund:
> I think the forkers over at SAGE use the purported v3 incompatibility
> issues as an excuse for forking GMP.

I have been approached by numerous people (from industry,
government, etc.) over the last three years about forking GMP.
GPLv3 was one of numerous factors that really pushed things
over the edge, though a fork would have happened anyways.

Torbjorn Granlund wrote:
> Seriously, please don't use this sort of rhetoric.  At least not
> before you've explained the actual problem.  I suspect the SAGE team's
> problem is mere stubbornness, in particular since they have not been
> able to produce one single reason for their problems with v3.  But I
> am all ears, should somebody spell it out.

It is no secret that the Sage project receives some funding from
Microsoft Research to produce free open source
mathematical software for use by their researchers.  See

for a list of organizations that fund Sage development.
A company-wide requirement at Microsoft is that they do not run any
GPLv3 code, not even binaries.  This is not surprising in light
of numerous quotes by Stallman about how GPLv3 was designed
partly to attack Microsoft.  For example:

 Stallman: "The point of the GPLv3 conditions that apply to the
 Novell/Microsoft deal is to give the rest of the community a defense
 against Microsoft's patent threats. If these conditions do their job,
 the result will be that Microsoft never goes beyond threats, and the
 community is safe."

This is one straightforward reason why GPLv3+ only code
is a problem for the Sage project.    It has nothing to do with
ideological stubborness by Sage developers (instead it is
ideological stubborness by Stallman).

If Microsoft  maintains this policy, then they will
also not run new versions of Mathematica, Maple,
Magma, that depend on any LGPLv3+ code.
So the problem Sage has will also be a problem for all
those projects.  And I guarantee you that people at Microsoft
know about this issue.

You probably don't like Microsoft, so I doubt we will find any sympathy
from you as a result of the above.  But rest assured
that the above issues with GPLv3 are NOT motivated by "mere
stubborness" by the *Sage team*.  So you are wrong about that.

William Stein
Associate Professor of Mathematics
University of Washington

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