Re: [PATCH v2] misra: add deviation of Rule 17.7

[Jan Beulich <jbeulich@xxxxxxxx>]

On 26.08.2025 09:36, Dmytro Prokopchuk1 wrote:
> --- a/automation/eclair_analysis/ECLAIR/deviations.ecl
> +++ b/automation/eclair_analysis/ECLAIR/deviations.ecl
> @@ -575,6 +575,11 @@ safe."
>  -config=MC3A2.R17.7,calls+={safe, "any()", 
> "decl(name(__builtin_memcpy||__builtin_memmove||__builtin_memset||cpumask_check))"}
>  -doc_end
>  
> +-doc_begin="It is safe to deviate functions like 'memcpy()', 'memset()', 
> 'memmove()', as they return a value purely for convenience,
> +their primary functionality (memory manipulation) remains unaffected, and 
> their return values are generally non-critical and seldom relied upon."
> +-config=MC3A2.R17.7,calls+={safe, "any()", 
> "decl(name(memcpy||memset||memmove))"}
> +-doc_end
> +
>  #
>  # Series 18.
>  #
> --- a/docs/misra/deviations.rst
> +++ b/docs/misra/deviations.rst
> @@ -576,6 +576,13 @@ Deviations related to MISRA C:2012 Rules:
>           - __builtin_memset()
>           - cpumask_check()
>  
> +   * - R17.7
> +     - It is safe to deviate functions like 'memcpy()', 'memset()', 
> 'memmove()',
> +       as they return a value purely for convenience, their primary 
> functionality
> +       (memory manipulation) remains unaffected, and their return values are
> +       generally non-critical and seldom relied upon.
> +     - Tagged as `safe` for ECLAIR.

I realize I may be overly nitpicky here, but in files named deviations.* I find 
it
odd to read "It is safe to deviate ...". I further find the use of "like" odd 
when
you enumerate the complete set anyway.

I wonder whether the deviation wants generalizing anyway: Informational return
values are generally okay to ignore. That is, the Eclair configuration would be
limited to the three functions for now, but the text / comment could already be
broader. Then, for example, open-coded uses of the corresponding builtin 
functions
would also be covered right away.

Jan