PATH=/usr/binutils2.22/bin/:$PATH:/opt/gcc-4.8/bin/ gcc or g++ ...
fakeroot apt-get install libmpc-dev libmpfr-dev libgmp3-dev wget ftp://ftp.gwdg.de/pub/misc/gcc/releases/gcc-4.8.1/gcc-4.8.1.tar.bz2 tar xvf gcc-4.8.1.tar.bz2 mkdir build cd build ../gcc-4.8.1/configure prefix=/opt/gcc-4.8 make make install