Optimize Box::default and Arc::default to construct more types in place
#137837
| Job | Run time |
|---|---|
| 11s | |
| 35m 46s | |
| 6m 57s | |
| 1h 13m 44s | |
| 53m 21s | |
| 0s | |
| 2h 49m 59s |