Rule 20.8 and #elif - Printable Version

Rule 20.8 and #elif - Printable Version

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Rule 20.8 and #elif - rgamble - 01-11-2017

It is pretty clear from the Amplification that this is not a violation of Rule 20.8:

Code:
#if 0

  #if 10  /* not evaluated, not a violation */

  #endif

#endif

and that this is:

Code:
#if 0

#elif 20  /* evaluated, violation */

#endif

but is the following intended to be a violation of this rule?:

Code:
#if 1

#elif 20  /* ??? */

#endif

It is not clear if the preprocessing directive #elif 20 is evaluated for the purpose of this rule.

Re: Rule 20.8 and #elif - misra-c - 23-11-2017

Code:
#if 1

#elif 20  /* rule 20.8 does not apply */

#endif

The #elif is considered to be in the code that is excluded and does not affect whether the code is excluded or not. Therefore the rule does not apply to the #elif controlling expression.