wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-8.repo sed -i 's/$releasever/8/g' /etc/yum.repos.d/CentOS-Base.repo yum install gcc-toolset-9-gcc gcc-toolset-9-gcc-c++ gcc -v # 显示 gcc 7 source /opt/rh/gcc-toolset-9/enable gcc -v # 显...