From: Brian Gough <bjg@gnu.org>
To: M Joonas Pihlaja <jpihlaja@cc.helsinki.fi>
Cc: gsl-discuss@sources.redhat.com
Subject: Re: Uninitialised rng state
Date: Mon, 09 Feb 2009 14:46:00 -0000 [thread overview]
Message-ID: <m3fxinacvh.wl%bjg@network-theory.co.uk> (raw)
In-Reply-To: <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
prev parent reply other threads:[~2009-02-09 14:46 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-02-07 6:30 M Joonas Pihlaja
2009-02-09 14:46 ` Brian Gough [this message]
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