Re: [PATCH v2] misra: add deviations of MISRA C Rule 5.5

[Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>]

On 2025-07-28 11:36, Jan Beulich wrote:
> On 25.07.2025 18:24, Dmytro Prokopchuk1 wrote:
> > --- a/docs/misra/deviations.rst
> > +++ b/docs/misra/deviations.rst
> > @@ -142,6 +142,31 @@ Deviations related to MISRA C:2012 Rules:
> >         memmove.
> >       - Tagged as `deliberate` for ECLAIR.
> >
> > +   * - R5.5
> > +     - Clashes between bitops functions and macros names are 
> > deliberate and are
> > +       needed for input validation and error handling, ensures that 
> > the size of
> > +       the object being pointed to by 'addr' meets the minimum 
> > requirements for
> > +       the bit operation, preventing unsafe operations on improperly 
> > sized data
> > +       types that could lead to undefined behavior or memory 
> > corruption.
> > +       The macros encapsulate this conditional logic into a single, 
> > reusable form;
> > +       which simplifies the code, avoids redundant function call.
> > +     - Specified macros should be ignored.
> At the risk of going too far with nitpicking: Who are "specified 
> macros" here? The
> text doesn't mention any names. In fact, the way it's written it could 
> be taken to
> mean all macros there, including any that are yet to be added. I don't 
> think such
> is appropriate for a deviation.
I agree with Jan here. Either you make a single deviation record 
encompassing all deviated macros or you have one per deviation (e.g., 
one for irq.h, one for grant_table.h and one for bitops.h) listing the 
macros that are considered. For bitops it might be a concern the actual 
functions going out of sync, but in that case you could just spell out 
the deviation and say "all pairs functions/macros in file <file> that 
are defined using the same identifier" or something similar.
> > +   * - R5.5
> > +     - Clashes between 'pirq_cleanup_check' function and macro names 
> > are deliberate.
> > +       The purpose is to ensure that the specific cleanup action 
> > ('pirq_cleanup_check')
> > +       is performed conditionally when the parameter 'event channel 
> > number' equals
> > +       zero, otherwise it does nothing.
> > +       This approach simplifies the code, avoids redundant function 
> > call.
> > +     - Specified macro should be ignored.
> Here it's clear which macro is meant, but ...
>
> > +   * - R5.5
> > +     - Clashes between grant table functions and macros names are 
> > deliberate.
> > +       These macros address differences in argument count during 
> > compile-time,
> > +       effectively discarding unused parameters to avoid warnings or 
> > errors
> > +       related to unused arguments.
> > +     - Specified macro should be ignored.
> ... here it again isn't.
>
> Jan
--
Nicola Vetrini, B.Sc.
Software Engineer
BUGSENG (https://bugseng.com)
LinkedIn: https://www.linkedin.com/in/nicola-vetrini-a42471253