Re: [PATCH] libstdc++: bvector: undef always_inline macro

[Jonathan Wakely <jwakely@redhat.com>]

On Thu, 9 Nov 2023 at 19:49, Alexandre Oliva <oliva@adacore.com> wrote:
>
> On Nov  9, 2023, Jonathan Wakely <jwakely@redhat.com> wrote:
>
> > But I've just realised we probably want to #undef the macro at the end
> > of bits/stl_bvector.h too.
>
> I'm not sure why (what if another libstdc++ header were to define the
> macro, includes stl_bvector.h, and then use the macro expecting it to
> still be there?), but I suppose this is what you mean.

It's consistent with all the other definitions of the macro in our
headers. We always define it locally and then undef it again at the
end of the header. You're right that that makes it rather hard to use
reliably.

>  Regstrapped on
> x86_64-linux-gnu just to be sure.  Ok to install?

OK thanks.


>
>
> From: Alexandre Oliva <oliva@adacore.com>
>
> It's customary to undefine temporary internal macros at the end of the
> header that defines them, even such widely-usable ones as
> _GLIBCXX_ALWAYS_INLINE, so do so in the header where the define was
> recently introduced.
>
>
> for  libstdc++-v3/ChangeLog
>
>         * include/bits/stl_bvector.h (_GLIBCXX_ALWAYS_INLINE): Undef.
> ---
>  libstdc++-v3/include/bits/stl_bvector.h |    2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/libstdc++-v3/include/bits/stl_bvector.h b/libstdc++-v3/include/bits/stl_bvector.h
> index 2b91af2005f2d..1b7648535c523 100644
> --- a/libstdc++-v3/include/bits/stl_bvector.h
> +++ b/libstdc++-v3/include/bits/stl_bvector.h
> @@ -1628,4 +1628,6 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
>  _GLIBCXX_END_NAMESPACE_VERSION
>  } // namespace std
>
> +#undef _GLIBCXX_ALWAYS_INLINE
> +
>  #endif
>
> --
> Alexandre Oliva, happy hacker            https://FSFLA.org/blogs/lxo/
>    Free Software Activist                   GNU Toolchain Engineer
> More tolerance and less prejudice are key for inclusion and diversity
> Excluding neuro-others for not behaving ""normal"" is *not* inclusive
>