C++2a synchronisation inefficient in GCC 11

[Ville Voutilainen]

On Fri, 26 Feb 2021 at 23:17, Jonathan Wakely <jwakely.gcc@gmail.com> wrote:

> I've considered whether we should put things in an inline namespace until they're stable, so that when we move it from std::__unstable to std:: there's an ABI break even if nothing else changes. Just to make it clear.
>
> Maybe even a different namespace for each release. std::__gcc11, then change it to __gcc12 just to make it incompatible.

Sounds like overkill to me, just an additional burden to
remove/stabilize that inline namespacing in the happy event that we
don't
actually need to break anything.