Re: [Bug-gsl] Uninitialized bytes in RNG state.

[Julian Seward]

> M Joonas Pihlaja wrote:
> > Valgrind complains about using uninitialised memory when
> > accessing all gsl_rng_size() bytes of the gsl_rng_state() arrays
> > returned by some rng types.
> >
> > 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.

Minor side comment that might make this kind of thing easier to track
down.  Valgrind versions 3.4.0 and later have a new option,
--track-origins=yes, which (at some performance cost) will tell you
the original source of uninitialised values.  This can be very helpful.

J