[cfe-dev] Relational operators on pointers

[Eli Friedman]

On Wed, Oct 12, 2011 at 3:13 PM, Stefan Marr
<mailinglists at stefan-marr.de> wrote:
> Hi:
>
> On 12 Oct 2011, at 23:54, David Chisnall wrote:
>
>> So, if you want to do a comparison between two unrelated pointers as unsigned values, the safest thing to do is cast them to uintptr_t and then do the comparison.
>
> Right, done, and failed. In this particular case, as Eli pointed out, some optimization is applied.

We shouldn't be messing with integer comparisons...

> All my casting to what ever type, and with whatever mechanism, did not help.
> Not even using temp variables of 64bit types with which ever signage.
> That all got just optimized away...
> Leaving me with a failing test without apparent reason.

What version of clang are you using?

-Eli