摘自：https://blog.csdn.net/lichen_net/article/details/70211204
mount CentOS的安装光盘，然后先后安装
rpm -ivh ppl-0.10.2-11.el6.x86_64.rpm
rpm -ivh cloog-ppl-0.15.7-1.2.el6.x86_64.rpm
rpm -ivh mpfr-2.4.1-6.el6.x86_64.rpm
rpm -ivh cpp-4.4.7-4.el6.x86_64.rpm
rpm -ivh kernel-headers-2.6.32-431.el6.x86_64.rpm
rpm -ivh glibc-headers-2.12-1.132.el6.x86_64.rpm
rpm -ivh glibc-devel-2.12-1.132.el6.x86_64.rpm
rpm -ivh gcc-4.4.7-4.el6.x86_64.rpm
rpm -ivh libstdc++-devel-4.4.7-4.el6.x86_64.rpm
rpm -ivh gcc-c++-4.4.7-4.el6.x86_64.rpm
一定要按顺序进行安装
部分安装提示already installed，没关系，
执行完，gcc就安装成功了