[Numpy-discussion] Aligning an array on Windows

[Timothy Hochberg]

[Much time passes]

I went ahead and added this warning. I kept thinking I should write a more
detailed explanation about why this is a problem, but I never got around to
it. At least this let's people know that there are some dragons to be wary
of.


-tim


On 5/28/07, Francesc Altet <faltet at carabos.com> wrote:
>
> El dv 25 de 05 del 2007 a les 14:19 -0700, en/na Timothy Hochberg va
> escriure:
> > Don't feel bad, when I had a very similar problem early on when we
> > were first adding multiple types and it mystified me for considerably
> > longer than this seems to have stumped you.
>
> Well, I wouldn't say the truth if I say that this doesn't help ;)
>
> Anyway, I think that this piece of code is dangerous enough and in order
> to avoid someone (including me!) tripping over it again, it would be
> nice to apply the next 'patch':
>
> Index: interp_body.c
> ===================================================================
> --- interp_body.c       (revision 3053)
> +++ interp_body.c       (working copy)
> @@ -89,6 +89,9 @@
>          unsigned int arg2 = params.program[pc+3];
>          #define      arg3   params.program[pc+5]
>          #define store_index params.index_data[store_in]
> +        /* WARNING: From now on, only do references to params.mem
> [arg[123]]
> +          & params.memsteps[arg[123]] inside the VEC_ARG[123] macros,
> +           or you will risk accessing invalid addresses.  */
>          #define reduce_ptr  (dest + flat_index(&store_index, j))
>          #define i_reduce    *(long *)reduce_ptr
>          #define f_reduce    *(double *)reduce_ptr
>
> Cheers,
>
> --
> Francesc Altet    |  Be careful about using the following code --
> Carabos Coop. V.  |  I've only proven that it works,
> www.carabos.com   |  I haven't tested it. -- Donald Knuth
>
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>



-- 
.  __
.   |-\
.
.  tim.hochberg at ieee.org
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