源码编译

1.查看当前gcc版本

# gcc --version

gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44)
Copyright (C) 2015 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.

2.安装默认的开发工具

# yum groupinstall "Development Tools"

3.获取安装包并解压

# cd /usr/local/src/
# wget http://ftp.gnu.org/gnu/gcc/gcc-7.3.0/gcc-7.3.0.tar.xz
# tar xvf gcc-7.3.0.tar.xz

4.安装依赖软件

# cd gcc-7.3.0/
# ./contrib/download_prerequisites

./contrib/download_prerequisites会帮我们下载、配置、安装依赖库，节约我们的时间和精力

5.生成Makefile文件

# ./configure -enable-checking=release -enable-languages=c,c++ -disable-multilib

6.编译

# make -j4
多核主机可以添加-j4，此步骤非常耗时

7.安装

make install

8.配置

# cd /usr/lib64
# cp /usr/local/src/gcc-7.3.0/stage1-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/libstdc++.so.6.0.24 .
# mv libstdc++.so.6 libstdc++.so.6.old
# ln -sv libstdc++.so.6.0.22 libstdc++.so.6

9.查看升级后的gcc版本

# gcc --version

yum安装

yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/centos-release-scl-2-3.el7.centos.noarch.rpm
yum install devtoolset-9-gcc-c++

临时生效: scl enable devtoolset-9 bash 或者source /opt/rh/devtoolset-9/enable

永久生效: echo "source /opt/rh/devtoolset-9/enable" >>/etc/profile

推荐yum安装，方便快捷。