| @@ -450,8 +450,13 @@ mod mut_ptr; |
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/// Executes the destructor (if any) of the pointed-to value. |
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/// |
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-/// This is semantically equivalent to calling [`ptr::read`] and discarding |
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+/// This is almost the same as calling [`ptr::read`] and discarding |
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/// the result, but has the following advantages: |
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+// FIXME: say something more useful than "almost the same"? |
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+// There are open questions here: `read` requires the value to be fully valid, e.g. if `T` is a |
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+// `bool` it must be 0 or 1, if it is a reference then it must be dereferenceable. `drop_in_place` |
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+// only requires that `*to_drop` be "valid for dropping" and we have not defined what that means. In |
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+// Miri it currently (May 2024) requires nothing at all for types without drop glue. |
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/// |
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/// * It is *required* to use `drop_in_place` to drop unsized types like |
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/// trait objects, because they can't be read out onto the stack and |