Re: [gnugo-devel] Cast to unsigned

[Gunnar Farneback]

Arend wrote:
> > Arend, you (I think) introduced casts to unsigned in some comparisons in
> > cache.c.  One of them is in tt_get() and looks like this:
> >
> >   if ((unsigned) remaining_depth <= hn_get_remaining_depth(*node)) {
> >     if (result)
> >       *result = hn_get_result1(*node);
> >     return 2;
> >   }
> >
> > These give warnings about comparison between singed and unsigned,
> > and before I try to fix them, I think that I must understand the
> > reason for the cast. Can you elaborate?
> 
> These were to avoid compiler warnings when .data in the hash nodes
> was still unsigned (as it has to be).

Does it really? I think it works with int too, although I would agree
that unsigned makes it clearer, in particular if the highest bit is
used. If we change to unsigned I would suggest adding casts to the
hn_get_* macros instead. It should be cleaner than having lots of
casts spread over the code.

/Gunnar