autobuild[sn-devel-144]: intermittent test failure detected

[autobuild]

The autobuild test system (on sn-devel-144) has detected an intermittent failing test in 
the current master tree.

The autobuild log of the failure is available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-08-10-1247/flakey.log

The failure seems to be in the "samba-none-env" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-08-10-1247/samba-none-env.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-08-10-1247/samba-none-env.stdout
  
The top commit at the time of the failure was:

commit 75287495f2e16e333ce1afe9d1b168b951350053
Author: Douglas Bagnall <douglas.bagnall at catalyst.net.nz>
Date:   Fri Aug 10 16:11:58 2018 +1200

    samba-tool drs showrepl tests: improve debugging for mystery error
    
    Under some circumstances the samba-tool command is failing with no
    stdout output at all, leaving few clues in the logs.
    
    Signed-off-by: Douglas Bagnall <douglas.bagnall at catalyst.net.nz>
    Reviewed-by: Garming Sam <garming at catalyst.net.nz>
    
    Autobuild-User(master): Douglas Bagnall <dbagnall at samba.org>
    Autobuild-Date(master): Fri Aug 10 09:27:03 CEST 2018 on sn-devel-144

and the last 50 lines of the stdout log were:

[213(3084)/248 at 20m34s] pidl.samba-ndr
[214(3115)/248 at 20m35s] pidl.samba3-cli
[215(3123)/248 at 20m35s] pidl.samba3-srv
[216(3124)/248 at 20m35s] pidl.tdr
[217(3130)/248 at 20m35s] pidl.test_util
[218(3136)/248 at 20m35s] pidl.typelist
[219(3192)/248 at 20m36s] pidl.util
[220(3264)/248 at 20m37s] pidl.wireshark-conf
[221(3313)/248 at 20m38s] pidl.wireshark-ndr
[222(3353)/248 at 20m39s] tdb.python
[223(3407)/248 at 20m40s] samba.tests.dsdb_lock
[224(3414)/248 at 21m52s] samba.tests.samba_tool.visualize
[225(3425)/248 at 21m54s] samba.tests.samba_tool.provision_password_check
[226(3429)/248 at 22m2s] samba.tests.samba_tool.help
[227(3430)/248 at 22m40s] samba.tests.domain_backup_offline
[228(3434)/248 at 24m15s] samba.tests.loadparm
[229(3437)/248 at 24m15s] samba4.blackbox.samba3dump
[230(3438)/248 at 24m15s] samba4.blackbox.upgrade
[231(3446)/248 at 24m41s] samba4.blackbox.provision.py
[232(3453)/248 at 25m28s] samba4.blackbox.supported_features
[233(3459)/248 at 25m37s] samba4.blackbox.start_backup
[234(3462)/248 at 25m45s] samba4.blackbox.upgradeprovision.current
[235(3469)/248 at 27m5s] samba4.blackbox.setpassword.py
[236(3475)/248 at 27m15s] samba4.blackbox.newuser.py
[237(3486)/248 at 27m27s] samba4.blackbox.group.py
[238(3515)/248 at 27m45s] samba4.blackbox.provision-backend
[239(3519)/248 at 27m53s] samba4.blackbox.renamedc.sh
[240(3530)/248 at 28m15s] samba4.dsdb.samdb.ldb_modules.unique_object_sids
[241(3536)/248 at 28m15s] samba4.dsdb.samdb.ldb_modules.encrypted_secrets
[242(3547)/248 at 28m15s] lib.audit_logging.audit_logging
UNEXPECTED(failure): lib.audit_logging.audit_logging.test_audit_get_timestamp(none)
REASON: Exception: Exception: difftime(after, actual) >= 0
../lib/audit_logging/tests/audit_logging_test.c:827: error: Failure!

FAILED (1 failures, 0 errors and 0 unexpected successes in 0 testsuites)

A summary with detailed information can be found in:
  ./bin/ab/summary
TOP 10 slowest tests
samba.tests.docs -> 179
samba.tests.docs.python3 -> 178
samba4.blackbox.upgradeprovision.release-4-0-0 -> 122
samba4.blackbox.upgradeprovision.alpha13 -> 120
samba4.blackbox.schemaupgrade -> 115
samba.tests.domain_backup_offline -> 95
samba4.blackbox.upgradeprovision.current -> 80
samba.tests.dsdb_lock -> 71
samba4.blackbox.dbcheck.release-4-0-0 -> 70
samba4.blackbox.dbcheck.release-4-1-0rc3 -> 59
ERROR: test failed with exit code 1