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Update rc.rs docs #140483

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Update rc.rs docs #140483

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2 changes: 1 addition & 1 deletion library/alloc/src/rc.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -3536,7 +3536,7 @@ impl<T> Default for Weak<T> {
}
}

// NOTE: We checked_add here to deal with mem::forget safely. In particular
// NOTE: We wrapping_add here to deal with mem::forget safely. In particular
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This is confusing in a different way: the wrapping_add does not offer the protection anymore, the strong == 0 conditional does.

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at the very least, it should mention clearly what actually implements the guard that handles the mem::forget, if it's going to mention any code.

// if you mem::forget Rcs (or Weaks), the ref-count can overflow, and then
// you can free the allocation while outstanding Rcs (or Weaks) exist.
// We abort because this is such a degenerate scenario that we don't care about
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