Re: [PATCH] fs/fcntl.c : don't test unsigned value for less than zero

[Herbert Xu <herbert@gondor.apana.org.au>]

Christoph Hellwig <hch@infradead.org> wrote:
>
>> No, it was exactly this patch:
>> http://www.ussg.iu.edu/hypermail/linux/kernel/0401.0/1816.html
> 
> Hmm.  Looks I absolutely disagree with Linus on this one ;-)

Me too.  The compiler doesn't really have much choice here.  If
it ignores all comparisons of unsigned integers to less than zero
then we could miss real bugs like this:

int foo(unsigned int val)
{
	return val < 0;
}

where the user probably wanted a signed comparison.

I suppose it could be smart and stay quiet about

val < 0 || val > BOUND

However, gcc is slow enough as it is without adding unnecessary
smarts like this.
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Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
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