[PATCH 0/2] MR868: ntdll, libwine: Avoid comparing the result of pointer arithmetic to zero.

[Zebediah Figura (＠zfigura)]

It's not exactly clear to me why gcc warns about this (and it's hard to find
reference for this specific flavor of -Waddress), but my understanding is that
arithmetic on well-defined pointers will never yield NULL. Of course, we are not
dealing with well-defined pointers here, but fortunately gcc does not complain
if we cast to intptr_t first.