How To Install gcc-8 on Ubuntu 20.04 to Resolve ‘Package gcc-8 has no installation candidate’ Error

In this guide, we will walk you through the process of installing gcc-8 on Ubuntu 20.04 to resolve the error: “Package gcc-8 has no installation candidate”. This error typically occurs when the gcc-8 package is not available in the default repositories of Ubuntu 20.04. We will provide two solutions to tackle this issue.

Prerequisites

Before we proceed, ensure that you have administrative access to your Ubuntu 20.04 system. This is necessary to execute the commands that we will be using in this guide.

Solution 1: Add Ubuntu 20.04 Repository

The first solution involves adding the Ubuntu 20.04 repository to your sources list. This repository contains the gcc-8 package.

Step 1: Update Package Lists

Start by updating your package lists with the following command:

sudo apt update

The sudo command is used to run the following command as a superuser. apt is the package handling utility in Ubuntu, and update is the command to resynchronize the package index files from their sources.

Step 2: Add Repository to Sources List

Next, open the /etc/apt/sources.list file using a text editor. In this example, we will use nano:

sudo nano /etc/apt/sources.list

At the end of the file, add the following line:

deb [arch=amd64] http://archive.ubuntu.com/ubuntu focal main universe

This line adds the Ubuntu 20.04 repository to your sources list. The [arch=amd64] part specifies that we are adding a repository for 64-bit packages.

Save the file and exit the text editor.

Step 3: Update Package Lists Again

Now, update the package lists again to include the new repository:

sudo apt update

Step 4: Install gcc-8 and g++-8

Finally, install gcc-8 and g++-8 with the following command:

sudo apt install gcc-8 g++-8

Solution 2: Manually Download and Install gcc-8

If the first solution does not work for you, you can try manually downloading and installing the gcc-8 package.

Step 1: Check if gcc-8 is Available

First, check if the gcc-8 package is available in the default repositories:

apt policy gcc-8

If the package is not available, you can proceed with the following steps.

Step 2: Download gcc-8

Download the gcc-8 package from a trusted source. For example, you can download it from Ubuntu 20.04 using the following commands:

sudo apt update
wget http://mirrors.kernel.org/ubuntu/pool/universe/g/gcc-8/gcc-8_8.4.0-3ubuntu2_amd64.deb

The wget command is a free utility for non-interactive download of files from the web. It supports HTTP, HTTPS, and FTP protocols.

Step 3: Install gcc-8

Finally, install the downloaded gcc-8 package using the following command:

sudo apt install ./gcc-8_8.4.0-3ubuntu2_amd64.deb

After successfully installing gcc-8, you can use the update-alternatives command to manage different versions of gcc if needed.

Conclusion

In this guide, we have provided two solutions to resolve the “Package gcc-8 has no installation candidate” error when trying to install gcc-8 on Ubuntu 20.04. Remember to always download software from trusted sources to avoid security risks. Also, using older versions of software may lead to compatibility issues. It is recommended to use containers or virtual machines with older operating systems to isolate vulnerabilities and minimize dependency problems.