Re: [PATCH 2/2] meson: fix CONFIG_ATOMIC128 check

[Marc-André Lureau]

Hi

On Mon, Feb 28, 2022 at 5:24 PM Peter Maydell <peter.maydell@linaro.org> wrote:
>
> On Mon, 28 Feb 2022 at 12:19, <marcandre.lureau@redhat.com> wrote:
> >
> > From: Marc-André Lureau <marcandre.lureau@redhat.com>
> >
> > testfile.c: In function 'main':
> > testfile.c:5:11: error: incorrect number of arguments to function 
> > '__atomic_load'
> >     5 |       y = __atomic_load(&x, 0);
> >       |           ^~~~~~~~~~~~~
> > testfile.c:6:7: error: argument 2 of '__atomic_store' must be a pointer type
> >     6 |       __atomic_store(&x, y, 0);
> >       |       ^~~~~~~~~~~~~~
> > testfile.c:7:7: error: argument 3 of '__atomic_compare_exchange' must be a 
> > pointer type
> >     7 |       __atomic_compare_exchange(&x, &y, x, 0, 0, 0);
> >       |       ^~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > And it must be linked with -latomic.
>
> As Philippe says, this isn't right. What the configure test
> is checking for is "do we have 128-bit atomics which are
> handled inline and specifically not via libatomic". The
> reason we can't use libatomic is documented in the comment
> starting "GCC is a house divided" in include/qemu/atomic128.h.

The arguments fix is still valid, no?