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soundness

The guarantee that no safe code can use an API to cause undefined behavior.

A safe function is sound if no sequence of safe calls can trigger undefined behavior through it; an unsound API is a bug even if no current caller misuses it.

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Examples

  • pick_two_mut(items, i, j) asserts i != j before using raw pointers, so no safe caller can get two &mut to the same item.

See also

safety contract undefined behavior unsafe block
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