use xcode ar and ranlib if present
#253
| Job | Run time |
|---|---|
| 17s | |
| 17s | |
| 27s | |
| 27s | |
| 15s | |
| 15s | |
| 33s | |
| 33s | |
| 1m 5s | |
| 1m 5s | |
| 46s | |
| 46s | |
| 1m 22s | |
| 1m 22s | |
| 31s | |
| 31s | |
| 34s | |
| 34s | |
| 31s | |
| 31s | |
| 33s | |
| 33s | |
| 38s | |
| 38s | |
| 45s | |
| 45s | |
| 1m 8s | |
| 1m 8s | |
| 1m 15s | |
| 1m 15s | |
| 1m 18s | |
| 1m 18s | |
| 1m 3s | |
| 1m 3s | |
| 1m 53s | |
| 1m 53s | |
| 48s | |
| 48s | |
| 48s | |
| 59s | |
| 58s | |
| 58s | |
| 35m 7s |