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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/111077] atomic_ref compare_exchange_strong doesn't properly
 ignore padding bits
Date: Sat, 19 Aug 2023 19:36:19 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111077

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|libstdc++                   |c++

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The calls for clearing the padding are there before eiline:
```
  std::__atomic_impl::__clear_padding<main()::HasPadding> (__exp_28);
  _4 =3D (int) __is_weak_30(D);
  _5 =3D std::__atomic_impl::__clear_padding<main()::HasPadding> (__i_31(D)=
);
  _6 =3D VIEW_CONVERT_EXPR<unsigned int>(*_5);
  _7 =3D std::__addressof<main()::HasPadding> (__val_33(D));
  retval.11_37 =3D __atomic_compare_exchange_4 (_7, __exp_28, _6, _4, __s_3=
5(D),
__f_16(D));
```

Oh we are not clearing the padding of the reference ...


Is this even well defined?=