Re: [XEN PATCH 10/11] xen/sched: add ASSERT_UNREACHABLE() to address MISRA C:2012 Rule 2.1

[Julien Grall <julien@xxxxxxx>]

Hi,

On 02/08/2023 15:38, Nicola Vetrini wrote:
> The break statement after the return statement is definitely unreachable.
> As such, an call to the ASSERT_UNREACHABLE() macro is added to signal
> the intentionality of such construct.
How about using unreachable() rather than ASSERT_UNREACHABLE()? The main 
difference is the later will hint the compiler that the code cannot be 
reached and will not crash Xen in debug build (this could be changed).
> Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>
> ---
> The break in the clause is mandated by Required Rule 16.3, which is
> not yet an accepted rule for Xen, but may be in the future.
> ---
>   xen/common/sched/core.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/xen/common/sched/core.c b/xen/common/sched/core.c
> index 022f548652..fcee902b4e 100644
> --- a/xen/common/sched/core.c
> +++ b/xen/common/sched/core.c
> @@ -2233,6 +2233,7 @@ static bool sched_tasklet_check_cpu(unsigned int cpu)
>           /* fallthrough */
>       case TASKLET_enqueued|TASKLET_scheduled:
>           return true;
> +        ASSERT_UNREACHABLE();
>           break;
>       case TASKLET_scheduled:
>           clear_bit(_TASKLET_scheduled, tasklet_work);
Cheers,

--
Julien Grall