Ubuntu 12.04 & 13.04 安装 GCC4.8.1

终于有了完整实现C++11的GCC 4.8.1.
给自己的系统升级吧。
下面的步骤可以安装GCC4.8.1, 内容来自：http://askubuntu.com/questions/312620/how-do-i-install-gcc-4-8-1-on-ubuntu-13-04
先安装一个软件
apt-get install python-software-properties
然后
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo update-alternatives --remove-all gcc
sudo update-alternatives --remove-all g++
sudo apt-get install gcc-4.8 -y
sudo apt-get install g++-4.8 -y
sudo apt-get install gcc-4.8-multilib -y
sudo apt-get install g++-4.8-multilib -y
sudo apt-get install gcc-4.8-doc -y
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 20
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 20
sudo update-alternatives --config gcc
sudo update-alternatives --config g++

sudo apt-get update
sudo apt-get upgrade -y
sudo apt-get dist-upgrade -y
最后用gcc --version检查一下，果然是4.8.1.
gcc --version
gcc (Ubuntu 4.8.1-2ubuntu1~13.04) 4.8.1
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

如果编译的时候，出现/usr/bin/c++ not found 错误
创建两个链接来解决：
ln -s /usr/bin/g++ /etc/alternatives/c++
ln -s /etc/alternatives/c++ /usr/bin/c++

同样，遇到cc找不到的时候，也创建链接：
ln -s /usr/bin/gcc /etc/alternatives/cc
ln -s /etc/alternatives/cc /usr/bin/cc


安装的文件可以通过下面的命令查找：
dpkg -L gcc-4.8
/.
/usr
/usr/bin
/usr/bin/gcc-ranlib-4.8
/usr/bin/gcov-4.8
/usr/bin/gcc-ar-4.8
/usr/bin/gcc-nm-4.8
/usr/bin/gcc-4.8
/usr/lib
/usr/lib/gcc
/usr/lib/gcc/x86_64-linux-gnu
/usr/lib/gcc/x86_64-linux-gnu/4.8
/usr/lib/gcc/x86_64-linux-gnu/4.8/lto1
/usr/lib/gcc/x86_64-linux-gnu/4.8/lto-wrapper
/usr/lib/gcc/x86_64-linux-gnu/4.8/collect2
/usr/lib/gcc/x86_64-linux-gnu/4.8/libgomp.spec
/usr/lib/gcc/x86_64-linux-gnu/4.8/libitm.spec
/usr/share
/usr/share/doc
/usr/share/doc/gcc-4.8-base
/usr/share/doc/gcc-4.8-base/README.ssp
/usr/share/doc/gcc-4.8-base/gomp
/usr/share/doc/gcc-4.8-base/gomp/changelog.gz
/usr/share/doc/gcc-4.8-base/changelog.gz
/usr/share/doc/gcc-4.8-base/gcc
/usr/share/doc/gcc-4.8-base/gcc/changelog.gz
/usr/share/doc/gcc-4.8-base/NEWS.html
/usr/share/doc/gcc-4.8-base/README.Bugs
/usr/share/doc/gcc-4.8-base/test-summary.gz
/usr/share/doc/gcc-4.8-base/itm
/usr/share/doc/gcc-4.8-base/itm/changelog.gz
/usr/share/doc/gcc-4.8-base/quadmath
/usr/share/doc/gcc-4.8-base/quadmath/changelog.gz
/usr/share/doc/gcc-4.8-base/NEWS.gz
/usr/share/man
/usr/share/man/man1
/usr/share/man/man1/gcov-4.8.1.gz
/usr/share/man/man1/gcc-nm-4.8.1.gz
/usr/share/man/man1/gcc-4.8.1.gz
/usr/share/man/man1/gcc-ar-4.8.1.gz
/usr/share/man/man1/gcc-ranlib-4.8.1.gz
/usr/bin/x86_64-linux-gnu-gcc-ranlib-4.8
/usr/bin/x86_64-linux-gnu-gcc-4.8
/usr/bin/x86_64-linux-gnu-gcc-nm-4.8
/usr/bin/x86_64-linux-gnu-gcc-ar-4.8
/usr/share/doc/gcc-4.8
/usr/share/man/man1/x86_64-linux-gnu-gcc-4.8.1.gz