Hypothesis: propose a possible defect explains the failure (Ockham's Razor: pick the simplest / closest to current work) based on the following
Prediction: What data could confirm or refute hypothesis
Experiment: collect data (running tests) to see if hypothesis is true
Observation: interpret experiment to support / refute hypothesis
Develop a fix, and run experiment again to see if reproduced defect is fixed.
Add compilation flags
Try other optimization levels
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