Fix #14308 FP nullPointerRedundantCheck with pointer reference parameter (*&)

[chrchr-github]

No description provided.

[pfultz2]

This is not really the correct fix. ValueFlowForward will check for variable changes.

The problem is that this comes from reverse analysis, so we need to traverse the subfunction in reverse as well. We don't really have a way to do that but we can skip the values that come from reverse analysis for now though.

[chrchr-github]

[...] but we can skip the values that come from reverse analysis for now though.

And how would we do that? Mark the values somehow?

[pfultz2]

[...] but we can skip the values that come from reverse analysis for now though.

And how would we do that? Mark the values somehow?

You could check the tokvlaue, but it is a little hacky how we use that for the starting point (I would like to add an origin field for this instead).

Another way is to mark them but we need to mark when it goes reverse and forward as we do forward analysis from reverse analysis so the state would need to switch back. It should probably be an enum of Forward. Reverse, and Unknown.

[chrchr-github]

Why would long long be appropriate for 24 bits, but not for 16? Is this a FP?

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

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0.0% Coverage on New Code
0.0% Duplication on New Code

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[chrchr-github]

Another way is to mark them but we need to mark when it goes reverse and forward as we do forward analysis from reverse analysis so the state would need to switch back. It should probably be an enum of Forward. Reverse, and Unknown.

There seem to be many places where values flow forward, so I haven't implemented the switching logic. We also have no tests that require it yet.