==Guide to install GCC 4.x.x and 5.x.x==

  sudo su
  cd /data/scratch

Download the source required from the following FTP servers: \\
GCC: http://ftp.gnu.org/gnu/gcc/

Install repo dependencies:
  yum install glibc-devel.i686 glibc glibc-devel glibc-static

Setup GCC prerequisites:
  
  tar -xf gcc-x.x.x.tar.gz
  cd gcc-x.x.x
  ./contrib/download_prerequisites
  

Compile GCC:

  ./configure --prefix=/opt/gcc-x.x.x --disable-multilib
  make -j4
  make install