[RFC] libstdc++: Make --enable-libstdcxx-backtrace=auto default to yes

[Jonathan Wakely]

On Mon, 4 Sept 2023 at 17:47, Hans-Peter Nilsson via Libstdc++
<libstdc++@gcc.gnu.org> wrote:
>
> > Date: Fri, 1 Sep 2023 12:16:40 +0100
> > Reply-To: Jonathan Wakely <jwakely@redhat.com>
> >
> > On Wed, 23 Aug 2023 at 17:03, Jonathan Wakely via Libstdc++
> > <libstdc++@gcc.gnu.org> wrote:
> > >
> > > Any objections to this? It's a C++23 feture, so should be enabled by
> > > default.
> >
> > I've pushed this to trunk, so let's see what breaks!
> >
> >
> > >
> > > -- >8 --
> > >
> > > This causes libstdc++_libbacktrace.a to be built by default. This might
> > > fail on some targets, in which case we can make the 'auto' choice expand
> > > to either 'yes' or 'no' depending on the target.
> > >
> > > libstdc++-v3/ChangeLog:
> > >
> > >         * acinclude.m4 (GLIBCXX_ENABLE_BACKTRACE): Default to yes.
> > >         * configure: Regenerate.
>
> Incidentally, should check_effective_target_stacktrace in
> libstdc++.exp also be adjusted to match; removing the
> _GLIBCXX_HOSTED condition?

No, it should still depend on is_hosted. The acinclude.m4 macro should
check that.