Re: [XEN PATCH 03/11] x86/uaccess: move declarations to address MISRA C:2012 Rule 2.1

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Wed, 2 Aug 2023, Nicola Vetrini wrote:
> The variable declarations inside macros {put,get}_unsafe_size are
> considered unreachable code, as they appear in a switch statement, before
> any clause. They are moved in the enclosing scope to resolve the violation.
> 
> No functional changes.
> 
> Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>

Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>


> ---
>  xen/arch/x86/include/asm/uaccess.h | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/xen/arch/x86/include/asm/uaccess.h 
> b/xen/arch/x86/include/asm/uaccess.h
> index 684fccd95c..a2aaab1e87 100644
> --- a/xen/arch/x86/include/asm/uaccess.h
> +++ b/xen/arch/x86/include/asm/uaccess.h
> @@ -191,11 +191,12 @@ struct __large_struct { unsigned long buf[100]; };
>  
>  #define put_unsafe_size(x, ptr, size, grd, retval, errret)                 \
>  do {                                                                       \
> +    long dummy_;                                                           \
> +                                                                           \
>      retval = 0;                                                            \
>      stac();                                                                \
>      switch ( size )                                                        \
>      {                                                                      \
> -    long dummy_;                                                           \
>      case 1:                                                                \
>          put_unsafe_asm(x, ptr, grd, retval, "b", "b", "iq", errret);       \
>          break;                                                             \
> @@ -218,11 +219,12 @@ do {                                                    
>                    \
>  
>  #define get_unsafe_size(x, ptr, size, grd, retval, errret)                 \
>  do {                                                                       \
> +    long dummy_;                                                           \
> +                                                                           \
>      retval = 0;                                                            \
>      stac();                                                                \
>      switch ( size )                                                        \
>      {                                                                      \
> -    long dummy_;                                                           \
>      case 1: get_unsafe_asm(x, ptr, grd, retval, "b", "=q", errret); break; \
>      case 2: get_unsafe_asm(x, ptr, grd, retval, "w", "=r", errret); break; \
>      case 4: get_unsafe_asm(x, ptr, grd, retval, "k", "=r", errret); break; \
> -- 
> 2.34.1
>