Re: [PATCH v2] docs/misra: add 14.3

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Thu, 7 Sep 2023, Jan Beulich wrote:
> On 07.09.2023 03:22, Stefano Stabellini wrote:
> > @@ -385,6 +386,17 @@ maintainers if you want to suggest a change.
> >       - A loop counter shall not have essentially floating type
> >       -
> >  
> > +   * - `Rule 14.3 
> > <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_14_03.c>`_
> > +     - Required
> > +     - Controlling expressions shall not be invariant
> > +     - Due to the extensive usage of IS_ENABLED, sizeof compile-time
> > +       checks, and other constructs that are detected as errors by MISRA
> > +       C scanners, managing the configuration of a MISRA C scanner for
> > +       this rule would be unmanageable. Thus, this rule is adopted with
> > +       a project-wide deviation on if ?: and switch statements.
> 
> Do we want to go as far as permitting this uniformly for all switch()? In
> my earlier reply I had included sizeof() for a reason.
 
I agree with you that it would be better to restrict it to only some
switch uses, rather than all of them.

But if we are going to restrict the deviation to switch(sizeof()), which
I think is a good idea and I am in favor, wouldn't it be better to
handle these cases as individual deviations? E.g. docs/misra/safe.json?
I am assuming there are only few cases like that and adding it here
makes the rule more complicated.

I am happy either way but I wanted to provide that as an option.


> Also (nit) there's at least a comma missing after "if". To make clear it's
> keywords that are meant, maybe better use if() / switch()?

OK I'll do that