fix NPE when enable unnecessary ReferenceDetection, for issue #3432 #6956
| Job | Run time |
|---|---|
| 8m 31s | |
| 6m 41s | |
| 8m 55s | |
| 5m 54s | |
| 6m 36s | |
| 6m 2s | |
| 6m 50s | |
| 7m 24s | |
| 5m 19s | |
| 8m 29s | |
| 6m 0s | |
| 5m 59s | |
| 1h 22m 40s |
| Job | Run time |
|---|---|
| 8m 31s | |
| 6m 41s | |
| 8m 55s | |
| 5m 54s | |
| 6m 36s | |
| 6m 2s | |
| 6m 50s | |
| 7m 24s | |
| 5m 19s | |
| 8m 29s | |
| 6m 0s | |
| 5m 59s | |
| 1h 22m 40s |