Karim BELABAS on Sat, 5 Oct 2002 16:53:43 +0200 (MEST)

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Re: division by zero error in matker(,1)

On Wed, 2 Oct 2002, Vasily Golyshev wrote:
> I was trying to find the kernel of an integer matrix 283x273,
> and some of the entries were 200 decimal digits long. I did
> check that each entry was a t_INT. What I got was the error message
> "division by zero in dvmdii". I was using matker(,1) function, in GP
> version 2-1-4 under Linux (actually the Windows version 2-0-17
> returned the same error message). Is that something that has been
> reported?

It was a garbage collection bug in matker(x,1), aka keri(). Not a stack
corruption, simply [ during "random GC" for huge inputs ] the routine forgot
to preserve a pointer that would be needed later.

If you update from the CVS (stable or development) version, the problem
should be gone.

Thanks for spotting this!

Karim Belabas                    Tel: (+33) (0)1 69 15 57 48
Dép. de Mathematiques, Bat. 425  Fax: (+33) (0)1 69 15 60 19
Université Paris-Sud             Email: Karim.Belabas@math.u-psud.fr
F-91405 Orsay (France)           http://www.math.u-psud.fr/~belabas/
PARI/GP Home Page: http://www.parigp-home.de/