[LLVMdev] C as used/implemented in practice: analysis of responses

[Renato Golin]

On 3 July 2015 at 05:17, David Keaton <dmk at dmk.com> wrote:
>> Consider:
>> y is positive
>> a = x + y (signed overflow, wrapping "expected")
>> if (a >= x)
>>    store out of bounds
>> ===>
>> store out of bounds
>
>
>      Right.  This is not prevented because the programmer has specified an
> out-of-bounds store.  However, if the programmer had not done so, the
> implementation would be prevented from making a transformation that results
> in an out-of-bounds store.

As is most of the original questions that had any traction. All
related to odd pointer handling (position, arithmetic, representation,
lifetime, etc), which all (?) end up as critical undefined behaviour.

cheers,
--renato