Re: [XEN PATCH v2 1/3] automation/eclair: tag function calls to address violations of MISRA C:2012 Rule 13.1

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Mon, 4 Dec 2023, Simone Ballarin wrote:
> On 02/12/23 04:19, Stefano Stabellini wrote:
> > On Fri, 24 Nov 2023, Simone Ballarin wrote:
> > > Rule 13.1: Initializer lists shall not contain persistent side effects
> > > 
> > > Invocations of functions in initializer lists cause violations of rule
> > > 13.1 if the called functions are not tagged with __attribute_pure__ or
> > > __attribute_const__ as they can produce persistent side effects.
> > > 
> > > Handling these violations with  attributes is not always possible: the
> > > pure and const attributes may cause unwanted and potentially dangerous
> > > optimisations.
> > > 
> > > To avoid this problem ECLAIR allows using the same attributes in the
> > > -call_properties setting. Additionally, it adds the noeffect attribute
> > > with the following definition:
> > > "like pure but can also read volatile variable not triggering side
> > > effects"
> > > 
> > > These patch tags some functions used in initializer lists to address
> > > violations of Rule 13.1.
> > > 
> > > No functional changes.
> > > 
> > > Signed-off-by: Simone Ballarin <simone.ballarin@xxxxxxxxxxx>
> > 
> > Ideally we should also list them somewhere in a document, maybe
> > docs/misra/deviations.rst? Or a new doc? It would be best if this info
> > wouldn't only exist in call_properties.ecl.
> 
> They are not actually deviations, but information that can help
> document the code: I suggest creating a new document.
> 
> Then, ECLAIR or any other tool will be able to retrieve these properties
> directly from this new file.
> 
> If you agree I will do it in a separate patch.

Yes a separate patch is fine. Please don't forget :-)