升级gcc

# 下载安装包

wget http://mirrors.aliyun.com/centos/7/os/x86_64/Packages/scl-utils-20130529-19.el7.x86_64.rpm
wget http://mirrors.aliyun.com/centos/7/os/x86_64/Packages/scl-utils-build-20130529-19.el7.x86_64.rpm
wget http://mirrors.aliyun.com/centos/7/sclo/x86_64/rh/Packages/d/devtoolset-9-binutils-2.32-16.el7.x86_64.rpm
wget http://mirrors.aliyun.com/centos/7/sclo/x86_64/rh/Packages/d/devtoolset-9-gcc-9.3.1-2.2.el7.x86_64.rpm
wget http://mirrors.aliyun.com/centos/7/sclo/x86_64/rh/Packages/d/devtoolset-9-gcc-c++-9.3.1-2.2.el7.x86_64.rpm
wget http://mirrors.aliyun.com/centos/7/sclo/x86_64/rh/Packages/d/devtoolset-9-libstdc++-devel-9.3.1-2.2.el7.x86_64.rpm
wget http://mirrors.aliyun.com/centos/7/sclo/x86_64/rh/Packages/d/devtoolset-9-runtime-9.1-0.el7.x86_64.rpm


# 打包(如果需要离线安装)
tar -czvf devtoolset9-vault.tar.gz ./

# 安装
yum install -y ./*.rpm


# 设置
scl enable devtoolset-9 bash

# 验证
gcc --version

# 写入全局环境变量
echo "source /opt/rh/devtoolset-9/enable" >> /etc/profile
source /etc/profile