I think I already know answer is no, but is it possible to use devtoolset-3- gcc in epel-6 builds now or in the future?
I'm asking in the context of being able to support Qt-5.6 (tls) for epel-6 which will need this.
See also: https://www.softwarecollections.org/en/scls/rhscl/devtoolset-3/
-- Rex