Step-by-step – GCC 12.1 Ubuntu 21.10 Installation

Installing

5. 5. Installing Dependencies

   Now to Install Required Dependencies
   Now install the Dependency Package with Multilib support with:

   sudo apt install build-essential libncurses-dev bison flex libssl-dev libelf-dev gcc-multilib

   Then access the Target Directory:

   cd ~/Downloads/gcc-12.*/

   And again to Download the Required Libraries play:

   ./contrib/download_prerequisites

6. 6. Setting up Environment

   Next Set Libraries Env Variable
   Eventually to Check the Target run:

   find /usr/ -name crti*

   Then Output should be as:
   /usr/lib/x86_64-linux-gnu/crti.o
   So in this case then to Set up the Environment Variables use:

   export LIBRARY_PATH=/usr/lib/x86_64-linux-gnu

   And then amend the User’s Path to append the New shared Libraries:

   echo "export LD_LIBRARY_PATH=/usr/lib:/usr/local/lib:/usr/local/lib64:/usr/lib/x86_64-linux-gnu" >> ~/.bashrc

   Last, to reload it:

   bash

7. 7. Installing GCC 12.1

   Finally, to Install GCC 12.1 on Ubuntu 21.10
   First, make a Build Directory:

   mkdir build

   Then entry it:

   cd build

   Configuring with:

   ../configure --enable-languages=c,c++,fortran,objc,obj-c++,go --prefix="/usr/local"

   Possibly customize the “languages” choiches in the above Command. To enable ADA and D Support see the Official Documentation.
   And then making it:

   make -j $(nproc)

   This Command to make it quicker using Multiples CPU Cores.
   Now take a long Time Out because the Build process will run for a while…
   Last, to make the Installation:

   sudo make install