[PATCH] Fixes sentinel warnings on GCC4

[David Hampton]

On Mon, 2005-12-05 at 22:19 -0500, Chris Shoemaker wrote:

> Fair enough.  I'll grab the original patch, remove redundant portions
> and apply it.  I'm convinced it's correct.  I figure it's easier to
> follow the standard than to figure out what weird systems people
> compile GnuCash on.  ( I don't even want to hazard a guess. ) 

I'm not concerned about whether the patch is correct (based on his last
patch it probably is) but whether its necessary.  Also, there's no
automated way to maintain the insistence that sentinels are explicitly
written as "(void *)NULL" [which is probably a safer cast than "(char
*)NULL"].   Sjoerd seems to have the only system that reports an uncast
NULL as an error.

David