This is Kubuntu 14.04.1 LTS / x86_64 with gcc 4.8.2 here.
I was able to built the newest ROOT v6.02/01 (14 October 2014) using [url=https://root-forum.cern.ch/t/installing-root-from-source/13647/1 favorite build method[/url].
All problems reported for [url=https://root-forum.cern.ch/t/root-v6-02-00-on-kubuntu-14-04-lts/18284/1 previous version[/url] are still there (including the “io/fildir.C” tutorial problem).
Additionally, on Linux one gets some annoying warnings (Mac OS X was used to create the archive?):
[…]$ tar -zxf root_v6.02.01.source.tar.gz
tar: Ignoring unknown extended header keyword 'SCHILY.dev’
tar: Ignoring unknown extended header keyword 'SCHILY.ino’
tar: Ignoring unknown extended header keyword ‘SCHILY.nlink’