github / codeql

CodeQL: the libraries and queries that power security researchers around the world, as well as code scanning in GitHub Advanced Security
https://codeql.github.com
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LGTM.com - false positive: if/elif/else comparison incorrect (unreachable, always true) #1989

Open kratsg opened 5 years ago

kratsg commented 5 years ago

Description of the false positive

alpha is a variable provided through the function and takes on any value from (-inf,+inf).

https://lgtm.com/projects/g/diana-hep/pyhf/snapshot/4a8bb79dcb5a18156090441c789404248a4872bb/files/src/pyhf/interpolators/code2.py?sort=name&dir=ASC&mode=heatmap#x490ee0f59f7109a3:1

(and related)

https://lgtm.com/projects/g/diana-hep/pyhf/snapshot/4a8bb79dcb5a18156090441c789404248a4872bb/files/src/pyhf/interpolators/code2.py?sort=name&dir=ASC&mode=heatmap#x4162964d9ead9482:1

matthewfeickert commented 5 years ago

If I change it to elif alpha >= -1 then LGTM is satisfied, but the logic is clearly the same as -1 <= alpha <= 1 in our case. So we're confused why LGTM is flagging this.