Fix for integer overflow in BinaryHeap for ZSTs #149451
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quaternic
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| // Recompute guarded left child for new hole position. | ||
| child = match hole.pos().checked_mul(2).and_then(|x| x.checked_add(1)) { | ||
| Some(idx) => idx, | ||
| None => return hole.pos(), | ||
| }; |
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I think the change would needlessly obfuscate this unsafe code. Under what conditions can the multiply overflow? (Note that the increment definitely can't.)
Both of the patched functions are structured similarly, and could be restructured to only do the let mut child = 2 * hole.pos() + 1; after checking the loop condition in a way that avoids the overflow.
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Fixes #149448
This PR fixes a potential integer overflow while calculating the children of a node for a BinaryHeap for zero sized types.