My bad on the name, misread it. As for the "doesn't solve it at all", but
it does. Think about it for a moment, if the MAX_INVALID_ADDRESS is always
defined as at least 512 and the 1st & last page (using page for
convenience, always relative to NULL) is always assigned as sealed
non-access pages then any time those pages are referenced then a segfault
is guaranteed to occur if it's not caught before hand for release/server
stability purposes. That in itself is useful to catch erroneous code using
uninitialised (as in no allocation made, not as in not assigned any solid
value) buffer pointers during debugging.

On Thu, 31 Jul 2025 at 16:30, Ville Voutilainen <ville.voutilainen_at_[hidden]>
wrote:

> On Thu, 31 Jul 2025 at 18:27, zxuiji <gb2985_at_[hidden]> wrote:
> >
> > villy that email was in response to the sysconf(_SC_PAGESIZE) being as
> little as 1, anyone programming for something embedded (which I presume the
> MMU would be) would not bother with using that call in the first place
>
> Try to spell my name correctly when responding to me.
>
> Yes, you also wrote
> "Then the answer to the potential null+-1 being valid is simple,
> mandate in the next standard that the 0+-PAGE_SIZE be premapped as
> sealed no rwx pages. That resolves the problem completely. They don't
> need to have anything mapped to them, just that they be mapped as
> invalid."
>
> which doesn't solve the problem "completely", or in fact, at all.
>