How to install gcc7

centOS 7

sudo yum install devtoolset-7-gcc

sudo mv /usr/bin/gcc{,-4.8.5}
sudo mv /usr/bin/g++{,-4.8.5}

#update alternatives
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8.5 30
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8.5 30

sudo update-alternatives --install /usr/bin/gcc gcc /opt/rh/devtoolset-7/root/usr/bin/gcc 50
sudo update-alternatives --install /usr/bin/g++ g++ /opt/rh/devtoolset-7/root/usr/bin/g++ 50

# install relevant libasan
sudo yum install devtoolset-7-libasan-devel.x86_64

# verify that configure shows correct gcc version + libasan is recognized as installed
#GCC version                              : 7.3.1