#2 Error bulding libGDF with Clang

[Luke]

Building with clang results in:
GDFHeaderAccess.cpp:28:14: error: unused variable 'epsilon_d' [-Werror,-Wunused-const-variable]

Full log here:
http://clang.debian.net/logs/2016-08-30/libgdf_0.1.2-2_unstable_clang.log

A debian bug was filed with a patch to fix the issue:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=751540