记一次centos gcc版本切换

gcc官网下载链接：Index of /software/gcc/releases

选择合适版本下载

下载后，安装：

tar -xvf gcc-4.8.5.tar.bz2
cd gcc-4.8.5/
./contrib/download_prerequisites
mkdir build
cd build
../configure --prefix=/usr/local/gcc4.8.5 --enable-checking=release --enable-languages=c,c++ --disable-multilib
make
make install

切换版本：

更改gcc：
sudo rm -rf /usr/local/bin/gcc 
ln -s /usr/local/gcc4.8.5/bin/gcc /usr/local/bin/gcc

更改g++：
sudo rm -rf /usr/local/bin/g++
ln -s /usr/local/gcc4.8.5/bin/gcc /usr/local/bin/gcc

更改c++：
sudo rm -rf /usr/local/bin/c++
ln -s /usr/local/gcc4.8.5/bin/gcc /usr/local/bin/gcc

cc1环境变量配置：

PATH="$PATH":/usr/local/gcc4.8.5/libexec/gcc/x86_64-unknown-linux-gnu/4.8.5
export PATH