使用yum升级gcc4.8.5到gcc4.9.2(Centos7)

第1步：获取repo
[root@localhost SPECS]# wget --no-check-certificate https://copr.fedoraproject.org/coprs/rhscl/devtoolset-3/repo/epel-6/rhscl-devtoolset-3-epel-6.repo -O /etc/yum.repos.d/devtoolset-3.repo
--2021-12-07 20:53:26--  https://copr.fedoraproject.org/coprs/rhscl/devtoolset-3/repo/epel-6/rhscl-devtoolset-3-epel-6.repo
Resolving copr.fedoraproject.org (copr.fedoraproject.org)... 13.212.21.54, 13.233.183.170, 13.250.126.156, ...
Connecting to copr.fedoraproject.org (copr.fedoraproject.org)|13.212.21.54|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://copr.fedorainfracloud.org/coprs/rhscl/devtoolset-3/repo/epel-6/rhscl-devtoolset-3-epel-6.repo [following]
--2021-12-07 20:53:27--  https://copr.fedorainfracloud.org/coprs/rhscl/devtoolset-3/repo/epel-6/rhscl-devtoolset-3-epel-6.repo
Resolving copr.fedorainfracloud.org (copr.fedorainfracloud.org)... 3.225.109.36, 2600:1f18:8ee:ae00:9d1f:4737:93ce:6db
Connecting to copr.fedorainfracloud.org (copr.fedorainfracloud.org)|3.225.109.36|:443... connected.
WARNING: cannot verify copr.fedorainfracloud.org's certificate, issued by ‘/C=US/O=Let's Encrypt/CN=R3’:
  Issued certificate has expired.
HTTP request sent, awaiting response... 200 OK
Length: 376 [text/plain]
Saving to: ‘/etc/yum.repos.d/devtoolset-3.repo’

100%[=============================================>] 376         --.-K/s   in 0s      

2021-12-07 20:53:28 (49.6 MB/s) - ‘/etc/yum.repos.d/devtoolset-3.repo’ saved [376/376]

第2步：安装devtoolset-3-gcc
[root@localhost SPECS]# yum -y install devtoolset-3-gcc 
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: mirror.compevo.com
 * centos-sclo-rh: mirrors.163.com
 * centos-sclo-sclo: mirrors.163.com
 * elrepo: mirror.rackspace.com
 * extras: repos.lax.quadranet.com
 * updates: linux.mirrors.es.net
Resolving Dependencies
--> Running transaction check
---> Package devtoolset-3-gcc.x86_64 0:4.9.2-6.el6 will be installed
--> Processing Dependency: devtoolset-3-binutils >= 2.22.52.0.1 for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Processing Dependency: devtoolset-3-runtime for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Processing Dependency: libgmp.so.3()(64bit) for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Processing Dependency: libmpfr.so.1()(64bit) for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Running transaction check
---> Package devtoolset-3-binutils.x86_64 0:2.24-18.el6 will be installed
---> Package devtoolset-3-gcc.x86_64 0:4.9.2-6.el6 will be installed
--> Processing Dependency: libgmp.so.3()(64bit) for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Processing Dependency: libmpfr.so.1()(64bit) for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
---> Package devtoolset-3-runtime.x86_64 0:3.1-12.el6 will be installed
--> Finished Dependency Resolution
Error: Package: devtoolset-3-gcc-4.9.2-6.el6.x86_64 (copr:copr.fedorainfracloud.org:rhscl:devtoolset-3)
           Requires: libmpfr.so.1()(64bit)
Error: Package: devtoolset-3-gcc-4.9.2-6.el6.x86_64 (copr:copr.fedorainfracloud.org:rhscl:devtoolset-3)
           Requires: libgmp.so.3()(64bit)
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest

若第2步报错，缺少两个安装包，执行第3步：
安装依赖包libmpfr.so.1和libgmp.so.3,下载链接如下：

mpfr：
链接：https://pan.baidu.com/s/1_adAchU_VGmEbSGRoMnhGg 
提取码：1234 

gmp：
链接：https://pan.baidu.com/s/1nA-LAjArEAGhWSFHTBj0og 
提取码：1234 

第4步，安装缺省包：
下载后，使用命令安装即可：
yum install compat-libmpfr-2.4.1-1.sl7.x86_64.rpm
yum install compat-libgmp-4.3.1-1.sl7.x86_64.rpm

第5步，再次安装devtoolset-3-gcc 
[root@localhost w0412]# yum install devtoolset-3-gcc
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: mirrors.163.com
 * centos-sclo-rh: mirrors.163.com
 * centos-sclo-sclo: mirrors.163.com
 * elrepo: mirror.rackspace.com
 * extras: mirrors.163.com
 * updates: mirrors.163.com
Resolving Dependencies
--> Running transaction check
---> Package devtoolset-3-gcc.x86_64 0:4.9.2-6.el6 will be installed
--> Processing Dependency: devtoolset-3-binutils >= 2.22.52.0.1 for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Processing Dependency: devtoolset-3-runtime for package: devtoolset-3-gcc-4.9.2-6.el6.x86_64
--> Running transaction check
---> Package devtoolset-3-binutils.x86_64 0:2.24-18.el6 will be installed
---> Package devtoolset-3-runtime.x86_64 0:3.1-12.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=======================================================================================
 Package    Arch   Version     Repository                                         Size
=======================================================================================
Installing:
 devtoolset-3-gcc
            x86_64 4.9.2-6.el6 copr:copr.fedorainfracloud.org:rhscl:devtoolset-3  24 M
Installing for dependencies:
 devtoolset-3-binutils
            x86_64 2.24-18.el6 copr:copr.fedorainfracloud.org:rhscl:devtoolset-3 5.1 M
 devtoolset-3-runtime
            x86_64 3.1-12.el6  copr:copr.fedorainfracloud.org:rhscl:devtoolset-3 1.1 M

Transaction Summary
=======================================================================================
Install  1 Package (+2 Dependent packages)

Total download size: 30 M
Installed size: 69 M
Is this ok [y/d/N]: y
Downloading packages:
warning: /var/cache/yum/x86_64/7/copr:copr.fedorainfracloud.org:rhscl:devtoolset-3/packages/devtoolset-3-binutils-2.24-18.el6.x86_64.rpm: Header V3 RSA/SHA1 Signature, key ID 094d442c: NOKEY
Public key for devtoolset-3-binutils-2.24-18.el6.x86_64.rpm is not installed
(1/3): devtoolset-3-binutils-2.24-18.el6.x86_64.rpm             | 5.1 MB  00:00:06     
(2/3): devtoolset-3-runtime-3.1-12.el6.x86_64.rpm               | 1.1 MB  00:00:01     
(3/3): devtoolset-3-gcc-4.9.2-6.el6.x86_64.rpm                  |  24 MB  00:00:13     
---------------------------------------------------------------------------------------
Total                                                     2.2 MB/s |  30 MB  00:13     
Retrieving key from https://download.copr.fedorainfracloud.org/results/rhscl/devtoolset-3/pubkey.gpg
Importing GPG key 0x094D442C:
 Userid     : "rhscl_devtoolset-3 (None) <rhscl#devtoolset-3@copr.fedorahosted.org>"
 Fingerprint: 143e 840e c0d0 ad21 e646 cdd8 fbce 6502 094d 442c
 From       : https://download.copr.fedorainfracloud.org/results/rhscl/devtoolset-3/pubkey.gpg
Is this ok [y/N]: y
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : devtoolset-3-runtime-3.1-12.el6.x86_64                              1/3 
  Installing : devtoolset-3-binutils-2.24-18.el6.x86_64                            2/3 
  Installing : devtoolset-3-gcc-4.9.2-6.el6.x86_64                                 3/3 
  Verifying  : devtoolset-3-binutils-2.24-18.el6.x86_64                            1/3 
  Verifying  : devtoolset-3-runtime-3.1-12.el6.x86_64                              2/3 
  Verifying  : devtoolset-3-gcc-4.9.2-6.el6.x86_64                                 3/3 

Installed:
  devtoolset-3-gcc.x86_64 0:4.9.2-6.el6                                                

Dependency Installed:
  devtoolset-3-binutils.x86_64 0:2.24-18.el6  devtoolset-3-runtime.x86_64 0:3.1-12.el6 

Complete!

第6步，安装devtoolset-3-gcc-c++
[root@localhost w0412]# yum install devtoolset-3-gcc-c++
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: mirrors.163.com
 * centos-sclo-rh: mirrors.163.com
 * centos-sclo-sclo: mirrors.163.com
 * elrepo: mirror.rackspace.com
 * extras: mirrors.163.com
 * updates: mirrors.163.com
Resolving Dependencies
--> Running transaction check
---> Package devtoolset-3-gcc-c++.x86_64 0:4.9.2-6.el6 will be installed
--> Processing Dependency: devtoolset-3-libstdc++-devel = 4.9.2-6.el6 for package: devtoolset-3-gcc-c++-4.9.2-6.el6.x86_64
--> Running transaction check
---> Package devtoolset-3-libstdc++-devel.x86_64 0:4.9.2-6.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=======================================================================================
 Package    Arch   Version     Repository                                         Size
=======================================================================================
Installing:
 devtoolset-3-gcc-c++
            x86_64 4.9.2-6.el6 copr:copr.fedorainfracloud.org:rhscl:devtoolset-3 8.4 M
Installing for dependencies:
 devtoolset-3-libstdc++-devel
            x86_64 4.9.2-6.el6 copr:copr.fedorainfracloud.org:rhscl:devtoolset-3 2.0 M

Transaction Summary
=======================================================================================
Install  1 Package (+1 Dependent package)

Total download size: 10 M
Installed size: 32 M
Is this ok [y/d/N]: y
Downloading packages:
(1/2): devtoolset-3-libstdc++-devel-4.9.2-6.el6.x86_64.rpm      | 2.0 MB  00:00:18     
(2/2): devtoolset-3-gcc-c++-4.9.2-6.el6.x86_64.rpm              | 8.4 MB  00:00:19     
---------------------------------------------------------------------------------------
Total                                                     534 kB/s |  10 MB  00:19     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : devtoolset-3-libstdc++-devel-4.9.2-6.el6.x86_64                     1/2 
  Installing : devtoolset-3-gcc-c++-4.9.2-6.el6.x86_64                             2/2 
  Verifying  : devtoolset-3-gcc-c++-4.9.2-6.el6.x86_64                             1/2 
  Verifying  : devtoolset-3-libstdc++-devel-4.9.2-6.el6.x86_64                     2/2 

Installed:
  devtoolset-3-gcc-c++.x86_64 0:4.9.2-6.el6                                            

Dependency Installed:
  devtoolset-3-libstdc++-devel.x86_64 0:4.9.2-6.el6                                    

Complete!

第7步，安装devtoolset-3-binutils
[root@localhost w0412]# yum install devtoolset-3-binutils
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: mirrors.163.com
 * centos-sclo-rh: mirrors.163.com
 * centos-sclo-sclo: mirrors.163.com
 * elrepo: mirror.rackspace.com
 * extras: mirrors.163.com
 
第8步，设置当前gcc版本：
scl enable devtoolset-3 bash
或
source /opt/rh/devtoolset-3/enable

第9步，查看gcc版本
[root@localhost w0412]# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/opt/rh/devtoolset-3/root/usr/libexec/gcc/x86_64-redhat-linux/4.9.2/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/opt/rh/devtoolset-3/root/usr --mandir=/opt/rh/devtoolset-3/root/usr/share/man --infodir=/opt/rh/devtoolset-3/root/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --enable-multilib --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --enable-languages=c,c++,fortran,lto --enable-plugin --with-linker-hash-style=gnu --enable-initfini-array --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.9.2-20150212/obj-x86_64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.9.2-20150212/obj-x86_64-redhat-linux/cloog-install --with-mpc=/builddir/build/BUILD/gcc-4.9.2-20150212/obj-x86_64-redhat-linux/mpc-install --with-tune=generic --with-arch_32=i686 --build=x86_64-redhat-linux
Thread model: posix
gcc version 4.9.2 20150212 (Red Hat 4.9.2-6) (GCC) 

至此，升级gcc完成。