gcc 4.8 on Raspberry Pi Wheezy

Ever needed gcc/g++ 4.8 on your wheezy? Then do

sudo nano /etc/apt/sources.list

Change content to

deb http://mirrordirector.raspbian.org/raspbian/ wheezy main contrib non-free rpi
deb http://archive.raspbian.org/raspbian wheezy main contrib non-free rpi
# Source repository to add
deb-src http://archive.raspbian.org/raspbian wheezy main contrib non-free rpi
deb http://mirrordirector.raspbian.org/raspbian/ jessie main contrib non-free rpi
deb http://archive.raspbian.org/raspbian jessie main contrib non-free rpi
# Source repository to add
deb-src http://archive.raspbian.org/raspbian jessie main contrib non-free rpi

Add preferences file

sudo nano /etc/apt/preferences

and insert

Package: *
Pin: release n=wheezy
Pin-Priority: 900
Package: *
Pin: release n=jessie
Pin-Priority: 300
Package: *
Pin: release o=Raspbian
Pin-Priority: -10

update package list

sudo apt-get update

Install gcc/g++ 4.8 from jessie repositories

sudo apt-get install -t jessie gcc-4.8 g++-4.8

To remove gcc/g++ alternative configuration (if there is any, there is none by default)

sudo update-alternatives --remove-all gcc 
sudo update-alternatives --remove-all g++

Install alternatives

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.6 20
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 50
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.6 20
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 50

Now 4.8 is your default compiler. You can verify it by

sudo gcc --version

If you want to change it, you can

sudo update-alternatives --config gcc
sudo update-alternatives --config g++