Benchmark trying to (dis-) prove whether Rustc or LLVM can optimize away a
superfluous some_collection.into_iter().collect::<SameCollection>() across
function boundaries.
$ cargo bench
into_iterator_collect_optimization/identity
time: [4.7218 ns 4.7423 ns 4.7630 ns]
Found 10 outliers among 100 measurements (10.00%)
3 (3.00%) high mild
7 (7.00%) high severe
into_iterator_collect_optimization/identity_as_iterator
time: [2.0384 us 2.0455 us 2.0532 us]
Found 6 outliers among 100 measurements (6.00%)
3 (3.00%) low mild
3 (3.00%) high mild