Document BinaryHeap unsafe functions #81706
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Thanks, this looks excellent. I think you are possibly right on the note about zero sized types; I think a PR adding the ZST bailout makes sense, but would need to do some more review on that. It would be good to add a FIXME comment into both methods that are likely affected to note down the problem.
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Squashed out the rebase fix commit (feel free to do so in the future). @bors r+ rollup |
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…e, r=Mark-Simulacrum Document BinaryHeap unsafe functions `BinaryHeap` contains some private safe functions but that are actually unsafe to call. This PR marks them `unsafe` and documents all the `unsafe` function calls inside them. While doing this I might also have found a bug: some "SAFETY" comments in `sift_down_range` and `sift_down_to_bottom` are valid only if you assume that `child` doesn't overflow. However it may overflow if `end > isize::MAX` which can be true for ZSTs (but I think only for them). I guess the easiest fix would be to skip any sifting if `mem::size_of::<T> == 0`. Probably conflicts with rust-lang#81127 but solving the eventual merge conflict should be pretty easy.
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…e, r=Mark-Simulacrum Document BinaryHeap unsafe functions `BinaryHeap` contains some private safe functions but that are actually unsafe to call. This PR marks them `unsafe` and documents all the `unsafe` function calls inside them. While doing this I might also have found a bug: some "SAFETY" comments in `sift_down_range` and `sift_down_to_bottom` are valid only if you assume that `child` doesn't overflow. However it may overflow if `end > isize::MAX` which can be true for ZSTs (but I think only for them). I guess the easiest fix would be to skip any sifting if `mem::size_of::<T> == 0`. Probably conflicts with rust-lang#81127 but solving the eventual merge conflict should be pretty easy.
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Rollup of 11 pull requests Successful merges: - rust-lang#81300 (BTree: share panicky test code & test panic during clear, clone) - rust-lang#81706 (Document BinaryHeap unsafe functions) - rust-lang#81833 (parallelize x.py test tidy) - rust-lang#81966 (Add new `rustc` target for Arm64 machines that can target the iphonesimulator) - rust-lang#82154 (Update RELEASES.md 1.50 to include methods stabilized in rust-lang#79342) - rust-lang#82177 (Do not delete bootstrap.exe on Windows during clean) - rust-lang#82181 (Add check for ES5 in CI) - rust-lang#82229 (Add [A-diagnostics] bug report template) - rust-lang#82233 (try-back-block-type test: Use TryFromSliceError for From test) - rust-lang#82302 (Remove unsafe impl Send for CompletedTest & TestResult) - rust-lang#82349 (test: Print test name only once on timeout) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
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BinaryHeapcontains some private safe functions but that are actually unsafe to call. This PR marks themunsafeand documents all theunsafefunction calls inside them.While doing this I might also have found a bug: some "SAFETY" comments in
sift_down_rangeandsift_down_to_bottomare valid only if you assume thatchilddoesn't overflow. However it may overflow ifend > isize::MAXwhich can be true for ZSTs (but I think only for them). I guess the easiest fix would be to skip any sifting ifmem::size_of::<T> == 0.Probably conflicts with #81127 but solving the eventual merge conflict should be pretty easy.