Re: [PATCH] lib/strtoul: fix MISRA R10.2 violation

[Jan Beulich <jbeulich@xxxxxxxx>]

On 14.05.2024 02:32, Stefano Stabellini wrote:
> Fix last violation of R10.2 by casting the result of toupper to plain
> char. Note that we don't want to change toupper itself as it is a legacy
> interface and it would cause more issues.

Can you point me at a single example where a new issue would arise? All
places I've spotted (including tolower() uses) would appear to benefit
from changing toupper() / tolower() themselves. Further, since they are
both wrapper macros only anyway, if any concern remained, fiddling with
the wrapper macros while leaving alone the underlying inline functions
would allow any such use site to simply be switched to using the inline
functions directly. As said, from looking at it I don't expect that
would be necessary, so instead I'd rather hope that eventually we can
do away with the wrapper macros, renaming the inline functions
accordingly.

Jan

> Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>
> ---
> I believe this is the last R10.2 violation
> 
> diff --git a/xen/lib/strtoul.c b/xen/lib/strtoul.c
> index a378fe735e..345dcf9d8c 100644
> --- a/xen/lib/strtoul.c
> +++ b/xen/lib/strtoul.c
> @@ -38,7 +38,7 @@ unsigned long simple_strtoul(
>  
>      while ( isxdigit(*cp) &&
>              (value = isdigit(*cp) ? *cp - '0'
> -                                  : toupper(*cp) - 'A' + 10) < base )
> +                                  : (char)toupper(*cp) - 'A' + 10) < base )
>      {
>          result = result * base + value;
>          cp++;