[m-rev.] for review: fix C compiler warnings for robdd.m

[Julien Fischer]

Hi,

On Sun, 7 Sep 2014, Zoltan Somogyi wrote:

> The best reviewer would be Peter Schachte or David Overton,

I can ask them if you like.

> but I don't think they are on the mailing list. Would anyone like to
> take a crack at it?

Having taken a crack at this code several times in the past, no! ;-)
(I don't think the code is even 64-bit clean, because I remember it
being trouble when ported Mercury to 64-bit systems.)

> Even just seeing whether it compiles cleanly on your machine would
> help.

Ok, I can do that.

> Note that while the code compiles without warning on my machine,
> I don't make guarantees about it working properly, since it seems
> that the code had bugs before I started. For example, it compiled
> with real hard errors (not warnings) if MR_ROBDD_STATISTICS
> was defined. Unfortunately, I don't think we ever had any tests
> that tested robdd operations specifically. Does anyone know otherwise?

I'm not aware of any such tests.  You can go ahead and commit this if
you want, I'll deal with any problems on other machines separately.

Cheers,
Julien.