Fixing Broken C/C++ Tooling on Ubuntu

Here we're assuming you want to have gcc versions 13 & 14 and clang versions 16 & 17 installed side by-side. Adjust to the versions you're installing.

You may also wish to adjust the priority (the last number in the update-alternatives commands below). A higher number means a higher priority.

We also assume you have previous broken installs of those. If this is not the case, replace reinstall with install in the below commands.

1. Install compilers:

   sudo apt reinstall gcc-13 g++-13 gcc-14 g++14 clang-16 clang-17
   

2. Install libs & headers:

   sudo apt reinstall libstdc++-13-dev libstdc++-14-dev libclang-16-dev libclang-17-dev
   

3. Set up symlinks manually:

   sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-13 10
   sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-13 10
   sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-14 20
   sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-14 20
   sudo update-alternatives --install /usr/bin/cc cc /usr/bin/gcc 30
   sudo update-alternatives --install /usr/bin/c++ c++ /usr/bin/g++ 30
   sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-16 10
   sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-17 20
   

4. Set the default C & C++ Compilers:

   sudo update-alternatives --set cc /usr/bin/gcc
   sudo update-alternatives --set c++ /usr/bin/g++
   

After this you should also be able to configure your defaults by running one of those:

sudo update-alternatives --config <tool>

Where <tool> is one of gcc, g++, clang, clang++, cc or c++.