HOWTO : Install GCC 7.x on Ubuntu 16.04.3 LTS

Some features require GCC 7.x to compile with, such as AVX-512.

sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt update
sudo apt install gcc-7

Set gcc-7 as default in order for the compilation.

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-7 60 --slave /usr/bin/gcc-ar gcc-ar /usr/bin/gcc-ar-7 --slave /usr/bin/gcc-nm gcc-nm /usr/bin/gcc-nm-7 --slave /usr/bin/gcc-ranlib gcc-ranlib /usr/bin/gcc-ranlib-7

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-5 60 --slave /usr/bin/gcc-ar gcc-ar /usr/bin/gcc-ar-5 --slave /usr/bin/gcc-nm gcc-nm /usr/bin/gcc-nm-5 --slave /usr/bin/gcc-ranlib gcc-ranlib /usr/bin/gcc-ranlib-5

Now, gcc-7 is the default compiler. To change back to gcc-5, you need to run :

sudo update-alternatives --config gcc

Then select gcc-5.

That's all! See you.