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Unsoundness

A sound function is one that can't trigger UB if its safety preconditions are satisfied.

An unsound function can trigger UB even if you satisfy the documented safety preconditions.

Unsound code is bad.

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• Read the definition of unsound functions.

• Translate into informal terms: unsound code is not nice. No, that's an understatement. Unsound code is BAD. Even if you play by the documented rules, unsound code can still trigger UB!

• We don't want any unsound code in our repositories.

• Finding unsound code is the primary goal of the code review.

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