warning: NULL used in arithmetic

[satyaakam goswami]

> The option -Werror makes warnings fatal.  With the more thorough
> checking of headers since gcc 4.1, it frequently becomes necessary to
> prevent -Werror from being set.  If I were to give a personal opinion,
> the idea of ascribing a numerical value to NULL seems sufficiently
> objectionable to deserve fatality.
>
so if i understand correctly now in gcc 4.1 all warnings are treated
as errors and it will not let the link phase happen and hence the
build will fail.

Satya