On Thu, Apr 23, 2020 at 01:48:00PM +0200, Jakub Jelinek wrote:
> On Thu, Apr 23, 2020 at 05:24:19AM -0500, Segher Boessenkool wrote:
> > > + inform (input_location,
> > > + "parameter passing for argument of type %qT "
> > > + "when C++17 is enabled changed to match C++14 "
> > > + "in GCC 10.1", type);
> >
> > It isn't "to match C++14". It simply is a bugfix, we didn't follow
> > the ABI before :-)
>
> The reason for the exact wording was to make it clearer to the user
> that C++17 doesn't have a different ABI from C++14 now, but it had in the
> older releases.
No, it used the same ABI then as well, but with a buggy implementation :-)
The ABI is not determined by GCC.
> Anyway, based on IRC discussion with Richard Sandiford on IRC, we should
> probably test type uids instead of type pointers because type uids aren't
> reused, but type pointers in a very bad luck case could be, and having the
> static var at filescope and GTY((deletable)) is an overkill (and with costs
> during GC time).
>
> Ok if it passes bootstrap/regtest?
>
> 2020-04-23 Jakub Jelinek <ja...@redhat.com>
>
> PR target/94707
> * config/rs6000/rs6000-call.c (rs6000_discover_homogeneous_aggregate):
> Use TYPE_UID (TYPE_MAIN_VARIANT (type)) instead of type to check
> if the same type has been diagnosed most recently already.
>
> --- gcc/config/rs6000/rs6000-call.c.jj 2020-04-23 09:59:12.002172006
> +0200
> +++ gcc/config/rs6000/rs6000-call.c 2020-04-23 13:42:10.037745872 +0200
> @@ -5739,14 +5739,15 @@ rs6000_discover_homogeneous_aggregate (m
> *n_elts = field_count;
> if (cxx17_empty_base_seen && warn_psabi)
> {
> - static const_tree last_reported_type;
> - if (type != last_reported_type)
> + static unsigned last_reported_type_uid;
> + unsigned uid = TYPE_UID (TYPE_MAIN_VARIANT (type));
> + if (uid != last_reported_type_uid)
> {
> inform (input_location,
> "parameter passing for argument of type %qT "
> "when C++17 is enabled changed to match C++14 "
> "in GCC 10.1", type);
> - last_reported_type = type;
> + last_reported_type_uid = uid;
> }
> }
> return true;
That looks fine, please go ahead. Thanks :-)
Segher
