On Wed, 2022-04-06 at 14:44 +0200, Jakub Jelinek wrote:
> On Wed, Apr 06, 2022 at 08:33:40PM +0800, Xi Ruoyao via Gcc-patches wrote:
> > Another MIPS function return ABI fix. Ok for trunk?
> >
> > --
> >
> > This fixes tmpdir-g++.dg-struct-layout-1/{t032,t059} failure. Clang++
> > ignores C++17 empty bases in return values as well.
> >
> > gcc/
> > * config/mips/mips.cc (mips_fpr_return_fields): Ignore
> > cxx17_empty_base_field_p fields.
> > ---
> > gcc/config/mips/mips.cc | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/gcc/config/mips/mips.cc b/gcc/config/mips/mips.cc
> > index 0f2492219f3..5010f99f761 100644
> > --- a/gcc/config/mips/mips.cc
> > +++ b/gcc/config/mips/mips.cc
> > @@ -6337,7 +6337,8 @@ mips_fpr_return_fields (const_tree valtype, tree
> > *fields,
> > i = 0;
> > for (field = TYPE_FIELDS (valtype); field != 0; field = DECL_CHAIN
> > (field))
> > {
> > - if (TREE_CODE (field) != FIELD_DECL)
> > + if (TREE_CODE (field) != FIELD_DECL
> > + || cxx17_empty_base_field_p (field))
> > continue;
> >
> > if (DECL_FIELD_CXX_ZERO_WIDTH_BIT_FIELD (field))
>
> Well, this won't diagnose the ABI change.
> So, if cxx17_empty_base_field_p, it should set some flag before continuing
> and if it is considered a fpr return and that flag is set, it should emit a
> -Wpsabi warning too.
Ok, will add it.
When I learnt from PR94704 fix I failed to notice the second commit
adding -Wpsabi warning :(.
--
Xi Ruoyao <[email protected]>
School of Aerospace Science and Technology, Xidian University