Re: [Qemu-arm] [PATCH] disas/libvixl: Fix VIXL_FALLTHROUGH macro for QEMU

[Peter Maydell]

On 15 May 2018 at 14:13, Stefan Weil <address@hidden> wrote:
> This is fixed in upstream vixl, in fact:
>
> https://git.linaro.org/arm/vixl.git/commit/?id=de326f850f736c3a337fda52845ed3d2e620cc02
>
> That fix will work for the moment, but is not sufficient for the future
> because it only supports gcc 7.x, but not gcc 8.x or later:
>
> +#elif __GNUC__ == 7
>
> How do we proceed with the code in QEMU? Do you have a plan to update the
> vixl code? As vixl is obviously no longer maintained on GitHub, I am not
> sure whom I could contact.

The github page points you to the linaro repo which is the new upstream.
That said, I think we're planning to deprecate vixl now we have the
capstone support. Richard, what's the status here? Could we just remove
the vixl code now?

> And what about my other question / suggestion:
>
> "I suggest to add and use a similar macro QEMU_FALLTHROUGH() for the rest of
> the code and can provide a patch if that's fine for everyone."
>
> gcc gives lots of fallthrough warnings, and many code locations don't
> contain a comment stating that the fall through is fine.

I guess that having the compiler check is better than finding them
later with coverity. It's a shame gcc doesn't support the standard
mechanism of using /* fallthrough */ to mark these, though.

thanks
-- PMM