Linux怎样更新Centos下Gcc版本支持C++17？
[[Linux下的软连接、软链接的方式]]
[[Linux使用的filesystem库来自于c++17提供的新特性]]
[[Linux下centos查看 GCC 、G++版本]]
[[Linux 下centos 查看 -std 是否支持 C17 ]]
Centos7快速安装gcc8.3.1 可支持C++17（附gcc相关链接整理）
centos7直接yum安装的那个gcc版本为4.8.5，对于大多数的需求来说都是低了。系统安装镜像里的那个版本也是4.8.5。 在g++ 7 以上的版本中添加了对c++17 的支持，所以为了工作需要现在需要升级到高版本。
sudo yum install centos-release-scl
sudo yum install devtoolset-8-gcc*
scl enable devtoolset-8 bash
source /opt/rh/devtoolset-8/enable
后边执行mv命令的时候如果报错不用太过惊慌，这几句是用来替换掉直接安装的4.8.5版本的，但是没安装4.8.5软链接建立的命令也还是要执行的。
mv /usr/bin/gcc /usr/bin/gcc-4.8.5
ln -s /opt/rh/devtoolset-8/root/bin/gcc /usr/bin/gcc
mv /usr/bin/g++ /usr/bin/g++-4.8.5
ln -s /opt/rh/devtoolset-8/root/bin/g++ /usr/bin/g++
mv /usr/bin/c++ /usr/bin/c++-4.8.5
ln -s /opt/rh/devtoolset-8/root/bin/c++ /usr/bin/c++
可以查看一下版本看看了
gcc --version
g++ --version
c++ --version
ubuntu16.04安装gcc-8 g++8.0
https://blog.csdn.net/dream_for_/article/details/117201988
GCC 命令行详解 -L 指定库的路径 -l 指定需连接的库名
https://blog.csdn.net/abc5382334/article/details/45049735
嵌入式Linux文件IO，GCC编译流程及参数分析，静态库创建和使用，ar crs libhello.a hello.o创建静态库,nm查看静态库中符号信息
https://blog.csdn.net/m0_37542524/article/details/83754738# Centos7快速安装gcc8.3.1 可支持C++17（附gcc相关链接整理）
实际手操：
直接贴命令行
[zryTest@master src]$ g++ ReadFileDemo-4.cpp -o Test-4
ReadFileDemo-4.cpp:6:22: fatal error: filesystem: No such file or directory
#include "
Fingerprint: c4db d535 b1fb ba14 f8ba 64a8 4eb8 4e71 f2ee 9d55
Package : centos-release-scl-rh-2-3.el7.centos.noarch (@extras)
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-SIG-SCLo
Is this ok [y/N]: y
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : 1:gmp-devel-6.0.0-15.el7.x86_64 1/14
Installing : mpfr-devel-3.1.1-4.el7.x86_64 2/14
Installing : libmpc-devel-1.0.1-3.el7.x86_64 3/14
Installing : scl-utils-20130529-19.el7.x86_64 4/14
Installing : devtoolset-8-runtime-8.1-1.el7.x86_64 5/14
Installing : devtoolset-8-libstdc++-devel-8.3.1-3.2.el7.x86_64 6/14
Installing : devtoolset-8-binutils-2.30-55.el7.2.x86_64 7/14
Installing : libgfortran5-8.3.1-2.1.1.el7.x86_64 8/14
Installing : devtoolset-8-gcc-8.3.1-3.2.el7.x86_64 9/14
Installing : devtoolset-8-libquadmath-devel-8.3.1-3.2.el7.x86_64 10/14
Installing : devtoolset-8-gcc-gfortran-8.3.1-3.2.el7.x86_64 11/14
Installing : devtoolset-8-gcc-c++-8.3.1-3.2.el7.x86_64 12/14
Installing : devtoolset-8-gcc-plugin-devel-8.3.1-3.2.el7.x86_64 13/14
Installing : devtoolset-8-gcc-gdb-plugin-8.3.1-3.2.el7.x86_64 14/14
Verifying : libgfortran5-8.3.1-2.1.1.el7.x86_64 1/14
Verifying : devtoolset-8-gcc-c++-8.3.1-3.2.el7.x86_64 2/14
Verifying : scl-utils-20130529-19.el7.x86_64 3/14
Verifying : devtoolset-8-libstdc++-devel-8.3.1-3.2.el7.x86_64 4/14
Verifying : devtoolset-8-runtime-8.1-1.el7.x86_64 5/14
Verifying : devtoolset-8-gcc-gfortran-8.3.1-3.2.el7.x86_64 6/14
Verifying : devtoolset-8-gcc-8.3.1-3.2.el7.x86_64 7/14
Verifying : 1:gmp-devel-6.0.0-15.el7.x86_64 8/14
Verifying : libmpc-devel-1.0.1-3.el7.x86_64 9/14
Verifying : devtoolset-8-gcc-plugin-devel-8.3.1-3.2.el7.x86_64 10/14
Verifying : devtoolset-8-libquadmath-devel-8.3.1-3.2.el7.x86_64 11/14
Verifying : mpfr-devel-3.1.1-4.el7.x86_64 12/14
Verifying : devtoolset-8-binutils-2.30-55.el7.2.x86_64 13/14
Verifying : devtoolset-8-gcc-gdb-plugin-8.3.1-3.2.el7.x86_64 14/14
Installed:
devtoolset-8-gcc.x86_64 0:8.3.1-3.2.el7 devtoolset-8-gcc-c++.x86_64 0:8.3.1-3.2.el7
devtoolset-8-gcc-gdb-plugin.x86_64 0:8.3.1-3.2.el7 devtoolset-8-gcc-gfortran.x86_64 0:8.3.1-3.2.el7
devtoolset-8-gcc-plugin-devel.x86_64 0:8.3.1-3.2.el7
Dependency Installed:
devtoolset-8-binutils.x86_64 0:2.30-55.el7.2 devtoolset-8-libquadmath-devel.x86_64 0:8.3.1-3.2.el7
devtoolset-8-libstdc++-devel.x86_64 0:8.3.1-3.2.el7 devtoolset-8-runtime.x86_64 0:8.1-1.el7
gmp-devel.x86_64 1:6.0.0-15.el7 libgfortran5.x86_64 0:8.3.1-2.1.1.el7
libmpc-devel.x86_64 0:1.0.1-3.el7 mpfr-devel.x86_64 0:3.1.1-4.el7
scl-utils.x86_64 0:20130529-19.el7
Complete!
[zryTest@master src]$ scl enable devtoolset-8 bash
[zryTest@master src]$ source /opt/rh/devtoolset-8/enable
[zryTest@master src]$ mv /usr/bin/gcc /usr/bin/gcc-4.8.5
mv: cannot move ‘/usr/bin/gcc’ to ‘/usr/bin/gcc-4.8.5’: Permission denied
[zryTest@master src]$ ln -s /opt/rh/devtoolset-8/root/bin/gcc /usr/bin/gcc
ln: failed to create symbolic link ‘/usr/bin/gcc’: File exists
[zryTest@master src]$ su -
Password:
Last login: Tue Mar 21 10:10:14 CST 2023 on pts/1
[root@master ~]# mv /usr/bin/gcc /usr/bin/gcc-4.8.5
[root@master ~]# ln -s /opt/rh/devtoolset-8/root/bin/gcc /usr/bin/gcc
[root@master ~]# mv /usr/bin/g++ /usr/bin/g++-4.8.5
[root@master ~]# ln -s /opt/rh/devtoolset-8/root/bin/g++ /usr/bin/g++
[root@master ~]# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/opt/rh/devtoolset-8/root/usr/libexec/gcc/x86_64-redhat-linux/8/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --enable-bootstrap --enable-languages=c,c++,fortran,lto --prefix=/opt/rh/devtoolset-8/root/usr --mandir=/opt/rh/devtoolset-8/root/usr/share/man --infodir=/opt/rh/devtoolset-8/root/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --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 --with-gcc-major-version-only --with-linker-hash-style=gnu --with-default-libstdcxx-abi=gcc4-compatible --enable-plugin --enable-initfini-array --with-isl=/builddir/build/BUILD/gcc-8.3.1-20190311/obj-x86_64-redhat-linux/isl-install --disable-libmpx --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux
Thread model: posix
gcc version 8.3.1 20190311 (Red Hat 8.3.1-3) (GCC)
[root@master ~]# g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/opt/rh/devtoolset-8/root/usr/libexec/gcc/x86_64-redhat-linux/8/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --enable-bootstrap --enable-languages=c,c++,fortran,lto --prefix=/opt/rh/devtoolset-8/root/usr --mandir=/opt/rh/devtoolset-8/root/usr/share/man --infodir=/opt/rh/devtoolset-8/root/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --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 --with-gcc-major-version-only --with-linker-hash-style=gnu --with-default-libstdcxx-abi=gcc4-compatible --enable-plugin --enable-initfini-array --with-isl=/builddir/build/BUILD/gcc-8.3.1-20190311/obj-x86_64-redhat-linux/isl-install --disable-libmpx --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux
Thread model: posix
gcc version 8.3.1 20190311 (Red Hat 8.3.1-3) (GCC)
[root@master ~]# c++ -v
Using built-in specs.
COLLECT_GCC=c++
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/4.8.5/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --with-linker-hash-style=gnu --enable-languages=c,c++,objc,obj-c++,java,fortran,ada,go,lto --enable-plugin --enable-initfini-array --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.8.5-20150702/obj-x86_64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.5-20150702/obj-x86_64-redhat-linux/cloog-install --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux
Thread model: posix
gcc version 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC)
[root@master ~]# mv /usr/bin/c++ /usr/bin/c++-4.8.5
[root@master ~]# ln -s /opt/rh/devtoolset-8/root/bin/c++ /usr/bin/c++
[root@master ~]# c++ -v
Using built-in specs.
COLLECT_GCC=c++
COLLECT_LTO_WRAPPER=/opt/rh/devtoolset-8/root/usr/libexec/gcc/x86_64-redhat-linux/8/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --enable-bootstrap --enable-languages=c,c++,fortran,lto --prefix=/opt/rh/devtoolset-8/root/usr --mandir=/opt/rh/devtoolset-8/root/usr/share/man --infodir=/opt/rh/devtoolset-8/root/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --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 --with-gcc-major-version-only --with-linker-hash-style=gnu --with-default-libstdcxx-abi=gcc4-compatible --enable-plugin --enable-initfini-array --with-isl=/builddir/build/BUILD/gcc-8.3.1-20190311/obj-x86_64-redhat-linux/isl-install --disable-libmpx --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux
Thread model: posix
gcc version 8.3.1 20190311 (Red Hat 8.3.1-3) (GCC)
[root@master ~]#
可以看到，这里的 gcc、 g++、c++、的版本已经到了8.3.1 2019版本了。
接下来再次通过 man g++ 查看 -std的介绍文档依旧 保持不变，
尝试更新man 手册 [[Linux 更新man说明手册，man中文手册]]
再次使用g++ 编译已经解决库找不到的问题了。 并且 -std=c++17已经可以识别出来了。
服务器高级架构体系：https://ke.qq.com/course/417774?flowToken=1010783