Better unwind table support + unwind protection in _start() and clone()
#17872
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| 1h 35m 37s | |
| 4h 43m 51s | |
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| 1h 20m 4s | |
| 4h 39m 53s | |
| 30m 40s | |
| 37m 45s | |
| 22h 3m 11s |