Re: Re: [patch] fix void* arithmetic

[Jeff Garzik <jeff@garzik.org>]

Hollis Blanchard wrote:
> On Tue, 2006-08-29 at 22:06 +0100, Ian Campbell wrote:
>> On Tue, 2006-08-29 at 15:24 -0500, Hollis Blanchard wrote:
>>> Hi Ian, I needed the following patch to avoid lots of these warnings:
>>> 	elf.c:238: warning: pointer of type `void *' used in arithmetic
>>>
>>> Fix void* arithmetic warnings.
>>> Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
>> Looks like PPC is the only arch using -Wpointer-arith, is there a reason
>> for that?
> 
> Is there are reason the other architectures *aren't* using it?
> 
> We have some extra warnings enabled because they've helped us in the
> past (such as -Wshadow). Given that we're just playing janitor for
> everyone else's code though, I think we're about to abandon that one.

Pointer arith is quite valid on void pointers, when using gcc and most 
other modern compilers.

Point of fact, any Linux kernel-related code REQUIRES that void* arith 
be valid, and not cause warnings.

As we see from your patch, all a cast to char* does is complicate the 
code, for zero gain.

	Jeff