This is the mail archive of the
gsl-discuss@sourceware.org
mailing list for the GSL project.
Re: Uninitialised rng state
- From: Brian Gough <bjg at gnu dot org>
- To: M Joonas Pihlaja <jpihlaja at cc dot helsinki dot fi>
- Cc: gsl-discuss at sources dot redhat dot com
- Date: Mon, 09 Feb 2009 14:44:34 +0000
- Subject: Re: Uninitialised rng state
- References: <Pine.OSF.4.61.0902070815060.347812@sirppi.helsinki.fi>
At Sat, 7 Feb 2009 08:30:41 +0200 (EET),
M Joonas Pihlaja wrote:
> One example is mt19937 whose state has lots of unsigned longs
> followed by an int. On a 64 bit machine the size of the state is
> 5000 bytes of which 4 bytes are pad bytes inserted by the
> compiler due to the mix of int/ulong. So later when I twiddle
> the state valgrind triggers on the uninitialised access. So I was
> wondering whether gsl_rng_alloc() really ought to calloc the
> state instead of mallocing it. Thoughts?
>
> As a workaround I'm currently clearing the entire state right
> after calling gsl_rng_alloc() and then calling gsl_rng_set(rng,
> gsl_rng_default_seed) right after. This does quell valgrind, but
> is it a sane thing to do?
Hello,
Valgrind 3.1 does not detect any errors for me when running the
gsl-1.12 rng test program on x86_64 with gcc 4.0.3 (apart from in the
fread and fwrite functions, where they're expected).
Can you send a full bug report to bug-gsl@gnu.org with the program,
complete valgrind error message, version of valgrind and gsl that you
use, and the compiler. Thanks.
--
Brian Gough