sudo yum -y install http://mirror.centos.org/centos/7/extras/x86_64/Packages/centos-release-scl-rh-2-3.el7.centos.noarch.rpm
sudo yum -y install http://mirror.centos.org/centos/7/extras/x86_64/Packages/centos-release-scl-2-3.el7.centos.noarch.rpm
sudo yum -y install http://mirror.centos.org/centos/7/sclo/x86_64/rh/Packages/l/llvm-toolset-7-clang-4.0.1-1.el7.x86_64.rpm
sudo yum install -y llvm-toolset-7-clang