rocksdb.autoinc_crash_safe_partition failed in buildbot, server crashed

rocksdb.autoinc_crash_safe_partition 'row' w3 [ fail ]  Found warnings/errors in server log file!

        Test ended at 2018-05-31 23:13:32

line

Attempting backtrace. You can use the following information to find out

^ Found warnings in /dev/shm/var/3/log/mysqld.1.err

ok

 - found 'core.5028' (0/0)

Trying 'dbx' to get a backtrace

gdb not found, cannot get the stack trace

Trying 'lldb' to get a backtrace from coredump /dev/shm/var/3/log/rocksdb.autoinc_crash_safe_partition-row/mysqld.1/data/core.5028

Compressed file /dev/shm/var/3/log/rocksdb.autoinc_crash_safe_partition-row/mysqld.1/data/core.5028

 - saving '/dev/shm/var/3/log/rocksdb.autoinc_crash_safe_partition-row/' to '/dev/shm/var/log/rocksdb.autoinc_crash_safe_partition-row/'