Fix two cases of signed integer overflow. #9073
Merged
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PR Summary
This tweaks two cases where there is potential for signed integer overflow:
rewind_scanlines
, we switch to unsigned intsnot_equal
, we switch for operations which cannot overflow.These cases were caught by matplotlib-using tests being run under
ASan with a check for signed integer
overflow.
PR Checklist
I did not see an easy way to add a test for this; I am happy to do so if someone has thoughts on a good place to include a test. (The "right" test to add would be a variant of the test suite running under ASan, but that seems a bit heavy for a small PR.)