Re: Preliminary results - was: Re: Question on BIGGEST_ALIGNMENT in GCC on NetBSD/m68k

[Geert Uytterhoeven <geert%linux-m68k.org@localhost>]

Hi Arnd,

On Tue, 6 Jan 2026 at 16:38, Arnd Bergmann <arnd%arndb.de@localhost> wrote:
> --- a/include/uapi/linux/rseq.h
> +++ b/include/uapi/linux/rseq.h
> @@ -142,9 +142,13 @@ struct rseq {
>         __u32 mm_cid;
>
>         /*
> -        * Flexible array member at end of structure, after last feature field.
> +        * Flexible array member at end of structure, after last feature field,
> +        * but overlapping with the padding.
>          */
> -       char end[];
> +       union {
> +               __u32 :32;
> +               __DECLARE_FLEX_ARRAY(char, end);
> +       };

After commit d6200245c75e832a ("rseq: Allow registering RSEQ with
slice extension"), the padding must be removed again.

>  } __attribute__((aligned(4 * sizeof(__u64))));
>
>  #endif /* _UAPI_LINUX_RSEQ_H */

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert%linux-m68k.org@localhost

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds