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From: "fsb4000 at yandex dot ru" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/97132] assume_aligned is not constexpr
Date: Mon, 21 Sep 2020 08:38:11 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D97132

--- Comment #4 from fsb4000 at yandex dot ru ---
(In reply to Jonathan Wakely from comment #3)
> I'll test this:
>=20
>      {
>        static_assert(std::has_single_bit(_Align));
>        _GLIBCXX_DEBUG_ASSERT((std::uintptr_t)__ptr % _Align =3D=3D 0);
> -      return static_cast<_Tp*>(__builtin_assume_aligned(__ptr, _Align));
> +      if (std::is_constant_evaluated())
> +       return __ptr;
> +      else
> +       return static_cast<_Tp*>(__builtin_assume_aligned(__ptr, _Align));
>      }
>  #endif // C++2a

Yes, should be fine.=20
We do same for Microsoft STL.=