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

From: Linus Torvalds
Date: Fri Dec 05 2014 - 13:50:24 EST


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.

Linus
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