Install Multiple GCC Versions.txt

1. Install dependences:
sudo apt update
sudo apt install build-essential
sudo apt-get install manpages-dev
sudo apt install software-properties-common


2. Add ppa repository:
sudo add-apt-repository ppa:ubuntu-toolchain-r/test

3. Install:

sudo apt install gcc-7 g++-7 gcc-8 g++-8 gcc-9 g++-9 gcc-10 g++-10

4. Configure alternatives

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-7 7
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-7 7
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-8 8
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-8 8
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-9 9
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-9 9
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-10 10
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-10 10

5. Optional you can choose specific version of gcc:

 execute this command in your terminal:
 
sudo update--alternatives --config gcc