build system used for epel7

[Farkas Levente]

hi,
what is the base architecture used under the current fedora build
system? since currently on rhel6 i can't update mock because of this bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1088966
on the other hand if i don't upgrade mock i can't build rhel7 packages
on an rhel6 host since mock 1.1.22 has other bug which already fixed on
newer mock.
so what is the current os version, kernel, mock  version on fedora
buildsys. and these system can be build epel6 and epel7 packages at the
same time?
thanks in advance.
regards.


-- 
  Levente                               "Si vis pacem para bellum!"