Re: [XEN PATCH 10/10] xen/sched: address violations of MISRA C Rule 20.7

[George Dunlap <george.dunlap@xxxxxxxxx>]

On Mon, Mar 18, 2024 at 11:54 AM Nicola Vetrini
<nicola.vetrini@xxxxxxxxxxx> wrote:
>
> MISRA C Rule 20.7 states: "Expressions resulting from the expansion
> of macro parameters shall be enclosed in parentheses". Therefore, some
> macro definitions should gain additional parentheses to ensure that all
> current and future users will be safe with respect to expansions that
> can possibly alter the semantics of the passed-in macro parameter.
>
> No functional change.
>
> Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>
> ---
>  xen/common/sched/private.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/xen/common/sched/private.h b/xen/common/sched/private.h
> index 459d1dfb11a5..c0e7c96d24f4 100644
> --- a/xen/common/sched/private.h
> +++ b/xen/common/sched/private.h
> @@ -540,7 +540,7 @@ static inline void sched_unit_unpause(const struct 
> sched_unit *unit)
>  }
>
>  #define REGISTER_SCHEDULER(x) static const struct scheduler *x##_entry \
> -  __used_section(".data.schedulers") = &x
> +  __used_section(".data.schedulers") = &(x)

Arguably this is safe, because any `x` which would be problematic in
this line wouldn't compile in the line above.

But it's almost certainly not worth the effort of documenting or deviating, so:

Acked-by: George Dunlap <george.dunlap@xxxxxxxxx>