The CLOBBER_CACHE_ALWAYS buildfarm members occasionally fail in
contrib/test_decoding with
TRAP: FailedAssertion("!(((bool)((relation)->rd_refcnt == 0)))", File: "relcache.c", Line: 1981)
for example here:
http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=markhor&dt=2014-12-14%2005%3A50%3A09
and here:
http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=markhor&dt=2014-12-13%2021%3A26%3A05
regards, tom lane