Avoid iteration when dropping HashMaps whose items don't need dropping
#31718
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This changes the performance of `drop` from linear to constant time for such `HashMap`s. Closes #31711.
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Cool! This is similar to the recently added conditional in Vec's Drop (#28531), but in this case it impacts both debug and release mode (the loop is never optimized out). |
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⌛ Testing commit f890772 with merge b9be526... |
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💔 Test failed - auto-win-gnu-32-nopt-t |
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@bors retry |
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This changes the performance of
dropfrom linear to constant time for suchHashMaps.Closes #31711.
r? @bluss