F.20 should exclude swap about cppcoreguidelines HOT 3 CLOSED

The parameters to a swap function are in-out parameters, not out parameters. So F.17 applies, not F.20.

The enforcement for F.20 says to flag non-const reference parameters that are not read before being written to (because that implies they are out parameters, not in-out parameters). That enforcement won't trigger for a conventional swap because you have to read them before writing to them.

What's the concrete problem here?

from cppcoreguidelines.

Mayben then the problem is that static code analysis tools detect this in a wrong way, or this is not well understand.

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I still don't understand what the actual issue is.

Are you getting diagnostics from some tool? Which tool? For which code? What does the diagnostic say?

So far there is nothing actionable here.

from cppcoreguidelines.