Comment 86 for bug 1750937

How to install the latest gcc compiler without pain

sudo add-apt-repository --remove ppa:ubuntu-toolchain-r/test # the best remedy whatsoever
sudo add-apt-repository --remove ppa:jonathonf/gcc-7.2 # (also broken https://askubuntu.com/questions/1009433/dependency-issues-while-installing-gcc-7-3-from-jonathon-fs-ppa)

sudo add-apt-repository -y ppa:jonathonf/gcc
sudo apt-get update
sudo apt-get install gcc-8 g++-8 # will install 7.3.0-5ubuntu1~16.04.york0
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-8 40 --slave /usr/bin/g++ g++ /usr/bin/g++-8

As Asus ROG user i'm aware of ongoing struggle with Nvidia driver, which is in conflict with Devian-based systems (https://bugs.debian.org/cgi-bin/pkgreport.cgi?pkg=nvidia-driver;dist=unstable https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=852152 ).

I disable NVidia card editing boot config

(Restart your computer and enter BOIS (hold down f2)
Change boot priority to boot to your USB Stick first.
Save and reboot
When the grub boot loader menu is visible highlight “Try Ubuntu GNOME without
installing” (use your up and down arrows)
 Press “e” on your keyboard, this will allow you to edit the boot config.
nouveau.modeset=0 tpm_tis.interrupts=0 acpi_osi=Linux
i915.preliminary_hw_support=1 idle=nomwait

Run the command: sudo apt-get update && sudo apt-get -y upgrade && sudo apt-get -y
dist-upgrade
Remove all Nvidia installs(if any), run this command:
sudo apt-get purge nvidia*
 Run the command: sudo apt-get install nvidia-361-updates nvidia-prime
 Reboot: sudo reboot

I used boot-repair software https://sourceforge.net/p/boot-repair/home/Home/
It was indispensable
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Links, used in combination with each other. Nothing is like a silver bullet.
https://jeremymdyson.wordpress.com/2016/04/27/ubuntugnome-16-04-on-asus-rog-gl552v/
https://www.howtogeek.com/114884/how-to-repair-grub2-when-ubuntu-wont-boot/
https://askubuntu.com/questions/624966/cant-login-after-nvidia-driver-install-v-14-04
https://www.reddit.com/r/linux/comments/4etbsw/nouveau_error_during_installation_of_ubuntu_gnome/