This seems the real issue (clicking under show result):
BuildError: mismatch when analyzing bacula-logwatch-7.0.5-7.fc21.noarch.rpm, rpmdiff output was:
error: cannot open Packages index using db5 - Permission denied (13)
error: cannot open Packages database in /var/lib/rpm
error: cannot open Packages database in /var/lib/rpm
removed REQUIRES bacula-director(armv7hl-32) = 7.0.5-7.fc21
added REQUIRES bacula-director(x86-64) = 7.0.5-7.fc21
It prints errors always on the same subpackage after all branches/arch built succesfully. Am I doing anything wrong? This is the first time I've seen this message.