Comments are needed for Rule 6-4-2? and should be placed inside the "else" block?

[misra cpp]

For MISRA C++:2008 the rationale is normative. For the current version of MISRA C and the next version of MISRA C++, the rationale isn't normative. That's because these standards may have an 'Amplification' section for each rule, to normatively expand on the headline.

So a final 'else' clause containing at least one statement or comment is required. Our expectation is that tools will be looking for a comment included in the {...} clause of the else