Build GCC-4.9.1 under Ubuntu 14.04

Follow the steps:

• Run the command:

 $ cd

• Download the source code for gcc-4.9.1:

  https://ftp.gnu.org/gnu/gcc/gcc-4.9.1/gcc-4.9.1.tar.bz2

• Create a new folder:

  $ mkdir gcc

• Copy the archive in the folder:

  $ cp ~/Downloads/gcc-4.9.1.tar.bz2 gcc

• Extract the archive:

  $ cd gcc
  $ tar -jxvf gcc-4.9.1.tar.bz2

• Change the current directory to gcc source folder and run the following command:

  $ cd gcc-4.9.1
  $ ./contrib/download_prerequisites

• Return to the previous folder:

  $ cd ..

• Create a new folder

  $ mkdir build

• Change the current directory to build:

  $ cd build

• Configure and build:

  $ sudo /home/<username>/gcc/gcc-4.9.1/configure --disable-multilib
  $ sudo make
  $ sudo make install