Re: [XEN PATCH v2 06/13] xen/efi: fix violations of MISRA C:2012 Rule 7.2

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Thu, 6 Jul 2023, Jan Beulich wrote:
> On 06.07.2023 01:37, Stefano Stabellini wrote:
> > On Wed, 5 Jul 2023, Simone Ballarin wrote:
> >> --- a/xen/common/efi/boot.c
> >> +++ b/xen/common/efi/boot.c
> >> @@ -34,13 +34,13 @@
> >>  #define EFI_REVISION(major, minor) (((major) << 16) | (minor))
> >>  
> >>  #define SMBIOS3_TABLE_GUID \
> >> -  { 0xf2fd1544, 0x9794, 0x4a2c, {0x99, 0x2e, 0xe5, 0xbb, 0xcf, 0x20, 
> >> 0xe3, 0x94} }
> >> +  { 0xf2fd1544U, 0x9794U, 0x4a2cU, {0x99U, 0x2eU, 0xe5U, 0xbbU, 0xcfU, 
> >> 0x20U, 0xe3U, 0x94U} }
> >>  #define SHIM_LOCK_PROTOCOL_GUID \
> >> -  { 0x605dab50, 0xe046, 0x4300, {0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 
> >> 0x8b, 0x23} }
> >> +  { 0x605dab50U, 0xe046U, 0x4300U, {0xabU, 0xb6U, 0x3dU, 0xd8U, 0x10U, 
> >> 0xddU, 0x8bU, 0x23U} }
> >>  #define APPLE_PROPERTIES_PROTOCOL_GUID \
> >> -  { 0x91bd12fe, 0xf6c3, 0x44fb, { 0xa5, 0xb7, 0x51, 0x22, 0xab, 0x30, 
> >> 0x3a, 0xe0} }
> >> +  { 0x91bd12feU, 0xf6c3U, 0x44fbU, { 0xa5U, 0xb7U, 0x51U, 0x22U, 0xabU, 
> >> 0x30U, 0x3aU, 0xe0U} }
> >>  #define EFI_SYSTEM_RESOURCE_TABLE_GUID    \
> >> -  { 0xb122a263, 0x3661, 0x4f68, {0x99, 0x29, 0x78, 0xf8, 0xb0, 0xd6, 
> >> 0x21, 0x80} }
> >> +  { 0xb122a263U, 0x3661U, 0x4f68U, {0x99U, 0x29U, 0x78U, 0xf8U, 0xb0U, 
> >> 0xd6U, 0x21U, 0x80U} }
> >>  #define EFI_SYSTEM_RESOURCE_TABLE_FIRMWARE_RESOURCE_VERSION 1
> > 
> > To be honest in these case I don't know if this is better or if it is
> > better to add U only to the first numbers (0xf2fd1544U, 0x605dab50U,
> > 0x91bd12feU, 0xb122a263U).
> 
> I'd prefer the latter, but I wonder whether that's in the spirit of Misra.

My understanding is that MISRA only requests U to be added where
actually needed. Everything else is up to us and our desire (or not) for
consistency.