How to Install GCC 13.1 on Debian Bullseye – Step-by-step

Switching

8. 8. Switching System GCC

   Finally, to easy Managing GCC Versions use update-alternatives
   So first install the New GCC 13.1 with:

   sudo update-alternatives --install /usr/bin/gcc gcc /usr/local/bin/gcc 10

   And then the System GCC with for instance:

   sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-9 20

   Eventually amend the above Command with the Path found on Step 2.
   Next to Switch between GCC Versions play:

   sudo update-alternatives --config gcc

   Last, to test the GCC in use:

   gcc -v



Congratulations, your GCC 13.1 should be now nicely working on Debian Bullseye. Good Luck! :)