On Fri, 2 Dec 2022, 17:51 Lénárd Szolnoki via Std-Discussion, <
std-discussion_at_[hidden]> wrote:

> Hi,
>
> On 2 December 2022 17:06:31 GMT, Edward Catmur via Std-Discussion <
> std-discussion_at_[hidden]> wrote:
> >
> >> Another could be freedom for compilers how they will layout stack
> >> > variables as you are not allowed to compare addresses of them.
> >
> >
> >I don't think undefined vs. unspecified makes much of a difference here;
> >the compiler could just always return false to every comparison between
> >pointers to automatic variables and you wouldn't be able to learn anything
> >about the layout.
>
> I don't think this is feasibly implementable. Consider `identity(&a) <
> identity(&b)`, where `identity` is opaque to the compiler.
>

Or just using intptr_t. But the compiler doesn't have to give consistent
answers to any of these.

Having said that an unspecified comparison still doesn't restrict the stack
> layout in any way.
>

Right, yeah.


> Cheers,
> Lénárd
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