Re: [RFC 1/2] compiler: use compiler to detect integer overflows

[Dan Carpenter]

On Fri, Dec 05, 2014 at 10:50:19AM -0800, Linus Torvalds wrote:
> On Fri, Dec 5, 2014 at 1:54 AM, Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
> >
> > There are some false positives which do:
> >
> >         if ((u16)(u16_foo + u16_bar) < u16_foo) {
> 
> Actually, the worse false positive is the ones that are pointer comparisons.
> 
> A compiler that does those as signed is just broken. It's happened,
> but it's *still* completely broken.
> 

Oh.  Wow...  That's embarrassing.  I thought they were signed for some
reason, and I thought it was weird, but I didn't think about it hard
enough...

I'll redo this.

regards,
dan carpenter
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