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-144/2018-05-02-0636/flakey.log

The failure seems to be in the "samba-ad-dc" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-05-02-0636/samba-ad-dc.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-05-02-0636/samba-ad-dc.stdout
  
The top commit at the time of the failure was:

commit bc71cd035c816de4ca98002860496bf8f5d50fe3
Author: Jeremy Allison <jra at samba.org>
Date:   Fri Apr 27 17:06:10 2018 -0700

    s3: VFS: Remove fsync_fn() from the VFS and all modules. VFS ABI change.
    
    Signed-off-by: Jeremy Allison <jra at samba.org>
    Reviewed-by: Ralph Boehme <slow at samba.org>
    
    Autobuild-User(master): Ralph Böhme <slow at samba.org>
    Autobuild-Date(master): Wed May  2 01:06:28 CEST 2018 on sn-devel-144

and the last 50 lines of the stdout log were:

[451(2954)/526 at 19m51s] samba.wbinfo_simple.domain-info=$DOMAIN(ad_member:local)
[452(2955)/526 at 19m51s] samba.wbinfo_simple.online-status(ad_member:local)
[453(2956)/526 at 19m51s] samba.wbinfo_simple.online-status.domain=BUILTIN(ad_member:local)
[454(2957)/526 at 19m52s] samba.wbinfo_simple.online-status.domain=$DOMAIN(ad_member:local)
[455(2958)/526 at 19m52s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(ad_member:local)
[456(2959)/526 at 19m52s] samba.wbinfo_simple.change-secret.domain=$DOMAIN(ad_member:local)
[457(2960)/526 at 19m53s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(ad_member:local)
[458(2961)/526 at 19m53s] samba.wbinfo_simple.online-status.domain=$DOMAIN(ad_member:local)
[459(2962)/526 at 19m53s] samba.wbinfo_simple.domain-users(ad_member:local)
[460(2963)/526 at 19m53s] samba.wbinfo_simple.domain-groups(ad_member:local)
[461(2964)/526 at 19m53s] samba.wbinfo_simple.name-to-sid=$DC_USERNAME(ad_member:local)
[462(2965)/526 at 19m53s] samba.wbinfo_simple.name-to-sid=$DOMAIN/$DC_USERNAME(ad_member:local)
[463(2966)/526 at 19m54s] samba.wbinfo_simple.user-info=$DOMAIN/$DC_USERNAME(ad_member:local)
[464(2967)/526 at 19m54s] samba.wbinfo_simple.user-groups=$DOMAIN/$DC_USERNAME(ad_member:local)
[465(2968)/526 at 19m54s] samba.wbinfo_simple.authenticate=$DOMAIN/$DC_USERNAME%$DC_PASSWORD(ad_member:local)
[466(2969)/526 at 19m54s] samba.wbinfo_simple.allocate-uid(ad_member:local)
[467(2970)/526 at 19m54s] samba.wbinfo_simple.allocate-gid(ad_member:local)
[468(2971)/526 at 19m54s] samba.wbinfo_sids2xids.(ad_member:local)(ad_member:local)
UNEXPECTED(failure): samba.wbinfo_sids2xids.(ad_member:local).sids2xids(ad_member:local)
REASON: Exception: Exception: failed to call wbcLookupName: WBC_ERR_INVALID_SID
Could not lookup name ADDOMAIN/
Couldn't delete specified entry
Entry deleted.
Couldn't delete specified entry
Entry deleted.
Couldn't delete specified entry
Couldn't delete specified entry
wbcSidToString(-512) failed: WBC_ERR_INVALID_PARAM
wbinfo_sids_to_unix_ids failed
Traceback (most recent call last):
  File "/memdisk/autobuild/fl/b1640665/samba-ad-dc/source3/script/tests/test_wbinfo_sids2xids_int.py", line 51, in <module>
    idtypes.append(result[0])
IndexError: list index out of range

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
samba3.local.nss(ad_dc:local) -> 83
samba3.raw.session krb5(ad_dc) -> 52
samba3.rpc.samr.passwords.pwdlastset(ad_dc) -> 52
samba3.smb2.session krb5(ad_dc) -> 35
samba4.blackbox.net_ads(ad_dc:client)(ad_dc:client) -> 33
samba3.rpc.schannel(ad_dc) -> 23
samba3.smb2.dir(ad_dc) -> 20
samba4.blackbox.trust_utils(fl2008r2dc:local)(fl2008r2dc:local) -> 19
samba3.smb2.ioctl(ad_dc) -> 19
samba3.base.delete(ad_dc) -> 19
ERROR: test failed with exit code 1