Re: octave2.1-headers: mkoctfile generated functions crash randomly

[Rafael Laboissiere]

Below is a bug report filed against the octave2.1-headers Debian package
(http://bugs.debian.org/340320).  See my comments after the included
message.

* Teemu Ikonen <address@hidden> [2005-11-22 19:34]:

> Package: octave2.1-headers
> Version: 2.1.72-4
> Severity: normal
> 
> Oct-functions generated by mkoctfile segfault randomly, but very often. For
> example, the following innocent-looking function:
> 
> -*-*-*-
> 
> #include <octave/oct.h>
> 
> DEFUN_DLD(uitest, args, , " ")
> {
>       int x = 20;
>       int y = 20;
>           
>       return octave_value(Matrix(y,x));
>                 
> }
>                 
> -*-*-*-
> 
> produces this when ran repeatedly:
> 
> octave:1> uitest();
> octave:2> uitest();
> octave:3> uitest();
> octave:4> uitest();
> panic: Segmentation fault -- stopping myself...
> attempting to save variables to octave-core'...
> save to octave-core' complete
> Segmentation fault
> 
> I can usually make Octave crash by running uitest less than 10 times.
> 
> Since I run a mixed system of testing and unstable, I'm rather certain that
> the crashes are caused by some kind of library version mismatch which the
> dependencies do not take into account. Octave 2.1.69 from sarge does not
> crash with the test above.
> 
> I would appreciate any ideas on how to get oct-files working again.

I confirm the problem here in my sid chroot.  Your program crashes in a
systematic way producing the following:

$ echo 'for i=1:100;printf("%i.",i);fflush(stdout);uitest();end' | octave -qf
1.2.3.4.5.6.7.8.9.panic: Segmentation fault -- stopping myself...
attempting to save variables to `octave-core'...
save to `octave-core' complete
Segmentation fault

What puzzles me is that it works fine in my etch (testing) system.  It looks
like a library problem.

How should I proceed in order to find where the bug comes from?

-- 
Rafael



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