> Karthikeyan, my apologies for the slow reply -- I posted this right before I went to bed.

No problem, thanks for the simplified program. I wrote a similar one based on doctest that fails with commit and passes before it. I am still confused about the commit impact and warnings also uses C code so hope someone else has some idea over this scenario. As you mentioned it seems to be about doctest that uses exec and compile. I can see the change in output since doctest has it's own internal stdout wrapper like contextlib but using the similar exec and compile statement as a standalone one doesn't reproduce this.