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Soundness

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

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• Read the definition of sound functions.

• Remind the students that the programmer who implements the caller is responsible for satisfying the safety precondition; the compiler is not helping.

• Translate into informal terms. Soundness means that the function is nice and plays by the rules. It documents its safety preconditions, and when the caller satisfies them, the function behaves well (no UB).

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