Re: [XEN PATCH v3 01/16] misra: add deviation for headers that explicitly avoid guards

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Mon, 11 Mar 2024, Jan Beulich wrote:
> On 11.03.2024 09:59, Simone Ballarin wrote:
> > Some headers, under specific circumstances (documented in a comment at
> > the beginning of the file), explicitly avoid inclusion guards: the caller
> > is responsible for including them correctly.
> > 
> > These files are not supposed to comply with Directive 4.10:
> > "Precautions shall be taken in order to prevent the contents of a header
> > file being included more than once"
> > 
> > This patch adds deviation cooments for headers that avoid guards.
> > 
> > Signed-off-by: Simone Ballarin <simone.ballarin@xxxxxxxxxxx>
> > 
> > ---
> > Changes in v3:
> > - fix inconsistent deviation ID
> > - change comment-based deviation text
> > Changes in v2:
> > - use the format introduced with doc/misra/safe.json instead of
> >   a generic text-based deviation
> > ---
> >  docs/misra/safe.json                        | 9 +++++++++
> >  xen/include/public/arch-x86/cpufeatureset.h | 1 +
> >  xen/include/public/errno.h                  | 1 +
> >  3 files changed, 11 insertions(+)
> 
> I understand something wants doing, but having such comments appear in public
> headers feels wrong to me. I'm afraid I have no good alternative suggestion.

Given that in both cases there is very nice explanation on how to use
the headers as an in-code comment just above, could we embed the
SAF-3-safe marker in the existing comment?

If not, I think we should go with this patch as is (I don't think it is
worth my, your, and Simone's time to look for alternatives).