Re: [PATCH v2 1/1] xen/arm: asm/atomic.h: Fix MISRA C 2012 Rule 20.7 violation

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Wed, 27 Jul 2022, Xenia Ragiadakou wrote:
> The macro parameter 'p' is used as an expression and needs to be enclosed in
> parentheses.
> 
> Signed-off-by: Xenia Ragiadakou <burzalodowa@xxxxxxxxx>

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


> ---
> 
> Changes in v2:
> - remove parentheses in the cases that p is not used as an expression that is
>   when it is used as a function argument
> 
>  xen/arch/arm/include/asm/atomic.h | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/xen/arch/arm/include/asm/atomic.h 
> b/xen/arch/arm/include/asm/atomic.h
> index ac2798d095..1f60c28b1b 100644
> --- a/xen/arch/arm/include/asm/atomic.h
> +++ b/xen/arch/arm/include/asm/atomic.h
> @@ -123,15 +123,15 @@ static always_inline void write_atomic_size(volatile 
> void *p,
>  }
>  
>  #define read_atomic(p) ({                                               \
> -    union { typeof(*p) val; char c[0]; } x_;                            \
> -    read_atomic_size(p, x_.c, sizeof(*p));                              \
> +    union { typeof(*(p)) val; char c[0]; } x_;                          \
> +    read_atomic_size(p, x_.c, sizeof(*(p)));                            \
>      x_.val;                                                             \
>  })
>  
>  #define write_atomic(p, x)                                              \
>      do {                                                                \
> -        typeof(*p) x_ = (x);                                            \
> -        write_atomic_size(p, &x_, sizeof(*p));                          \
> +        typeof(*(p)) x_ = (x);                                          \
> +        write_atomic_size(p, &x_, sizeof(*(p)));                        \
>      } while ( false )
>  
>  #define add_sized(p, x) ({                                              \
> -- 
> 2.34.1
>