설치된 gcc 버전 확인
dpkg -l | grep gcc | awk '{print $2}'
gcc
gcc-4.7
gcc-4.7-base:amd64
gcc-4.7-multilib
gcc-4.8
gcc-4.8-base:amd64
gcc-4.8-multilib
gcc-4.9
gcc-4.9-base:amd64
gcc-4.9-base:i386
gcc-4.9-multilib
gcc-6-base:amd64
gcc-6-base:i386
gcc-multilib
lib32gcc-4.7-dev
lib32gcc-4.8-dev
lib32gcc-4.9-dev
lib32gcc1
libgcc-4.7-dev:amd64
libgcc-4.8-dev:amd64
libgcc-4.9-dev:amd64
libgcc1:amd64
libgcc1:i386
libx32gcc-4.7-dev
libx32gcc-4.8-dev
libx32gcc-4.9-dev
libx32gcc1
multi lib 설치
sudo apt-get install gcc-4.x-multilib
http://askubuntu.com/questions/26498/choose-gcc-and-g-version