Re: Question about points-to analysis, global variables, IPA, and field sensitivity

[Richard Biener <richard.guenther@gmail.com>]

On Tue, Mar 30, 2021 at 1:39 PM Erick Ochoa <eochoa@gcc.gnu.org> wrote:
>
> > If the global is module local we should initialize it with NULL, yes.  If it is
> > not module local it should be initialized with NONLOCAL (that's both what
> > should currently happen correctly - it's needed for non-field-sensitive init
> > as well).
> >
>
> Awesome, thanks Richard! One more question: in the context of LTO,
> "module local" means the current partition?

Yes.

> I understand that IPA-PTA is a late SIMPLE_IPA_PASS but my
> understanding of the consequences of this is a little fuzzy. I think
> that IPA-PTA also runs in multiple partitions (unless a flag like
> -flto-partition=none is used), but there might be some issue with
> reduced precision. Perhaps this reduced precision comes from NONLOCAL
> constraints with symbols that cross partitions? (This is just
> speculation on my part, as I mention, my understanding is a little bit
> fuzzy.)

Yes.  Also (obviously) from function definitions not visible and thus
functions treated as external calls when they need not (because of LTO)

Richard.