CentOS follows the development of Red Hat Enterprise Linux (RHEL). RHEL strives to be a stable server platform, which means that it does not rush to include the latest versions of every software package.
As of the writing of this article, CentOS 6 officially distributes GCC v4.4.7. However, GCC v5.1 was recently released. Before that, v4.9.2 was available.
The official suggestion to needing a more recent version of GCC is that you should consider a different UNIX distribution which is more focused on supporting the latest versions of software packages.
Fortunately, you are able to install a more recent version of GCC on CentOS, leaving the older version still installed. This deviates from purely using the officially distributed software, but sometimes you may feel like you have little choice. You can run into some complications; for example, if you are installing third party kernel modules, they must be compiled using the same version of GCC used to build your kernel.
This article describes how to install the CentOS 6 officially supported version of GCC, and how to install a newer version as well. This article assumes that you have a freshly installed CentOS 6 VPS, although you can certainly follow the instructions on an existing VPS.
Even if you want to install a newer version of GCC from source, GCC itself is written in C++. Therefore, you first have to install an older C++ compiler.
(b) Create your own user account, and give it a password.
adduser <username>
passwd <username>
(c) Allow your user account to execute commands with root privileges, through the sudo command.
visudo
After the line "root ALL=(ALL) ALL"
Add the line "<username> ALL=(ALL) ALL"
--- If you aren't familiar with vi, go to the line "root ALL=(ALL) ALL".
--- Hit "o" to create a new line after that line and enter insert mode.
--- Type "<username> ALL=(ALL) ALL".
--- Hit ESC.
--- Type "ZZ" to save.
(d) Log out as root, and login to your user account.
sudo yum install gcc gcc-c++
gcc --version
May say: gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11)
g++ --version
May say: g++ (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11)
which gcc
/usr/bin/gcc
which g++
/usr/bin/g++
If you only want the CentOS officially supported version of GCC, you’re all set. If you need a more recent version of GCC, continue on.
sudo yum install svn texinfo-tex flex zip libgcc.i686 glibc-devel.i686
svn ls svn://gcc.gnu.org/svn/gcc/tags | grep gcc | grep release
gcc-2_95-release/
...
gcc-4_9_2_release/
gcc-5_1_0_release/
gcc-5_1_0_release/ and will download the sources into ~/sourceInstallations/gcc_5_1_0_release/.mkdir ~/sourceInstallations
cd ~/sourceInstallations
svn co svn://gcc.gnu.org/svn/gcc/tags/gcc_5_1_0_release/
cd gcc_5_1_0_release/
./contrib/download_prerequisites
--- Important, run this as shown, from the gcc_5_1_0_release directory.
--- Do not cd to the contrib directory
SWAP=/tmp/swap
dd if=/dev/zero of=$SWAP bs=1M count=500
mkswap $SWAP
sudo swapon $SWAP
cd ..
mkdir gcc_5_1_0_release_build/
cd gcc_5_1_0_release_build/
../gcc_5_1_0_release/configure && make && sudo make install && echo "success"
--- If your VPS has multiple cores, you can speed up the build by changing the middle part
--- of this line from "&& make &&" to "&& make -j <number of cores> &&".
--- You can see the number of cores your VPS has by running "nproc"
sudo swapoff $SWAP
rm /tmp/swap
hash -r
(Makes your login "forget" about the previously seen locations of gcc and g++)
gcc --version
May say: gcc (GCC) 5.1.0
g++ --version
May say: g++ (GCC) 5.1.0
which gcc
/usr/local/bin/gcc
which g++
/usr/local/bin/g++
echo "/usr/local/lib64" > usrLocalLib64.conf
sudo mv usrLocalLib64.conf /etc/ld.so.conf.d/
sudo ldconfig
--- This may say a file or two "is not an ELF file - it has the wrong magic bytes at the start."
--- You may ignore this message. It is silent about the work it successfully completed.
mkdir ~/code
cd ~/code
Create a file main.cpp that says:
#include <iostream>
using namespace std;
int main() {
cout << "Hello world!" << endl;
return 0;
}
--- One way to create this file is to run "vi main.cpp", hitting "i" to enter insert mode,
--- typing the above file, hitting ESC, and hitting "ZZ" to save.
g++ main.cpp -o main
./main
Hello World!
~/sourceInstallations folder will be taking up around 8.0GB. It’s probably wise to keep the folders, as there are optional configuration options you may need to use at some point in the future, and it would be faster to have a lot already done. Also, the build process makes logs that you can later check and work from if something goes wrong. But, after running sudo make install earlier, your installed GCC isn’t depending on anything in this directory, and space can be at a premium, so you can do this step and reclaim the 8.0GB or so.cd ~/
rm -rf sourceInstallations
--- Again, if you can spare the space, you may someday be happy to have left it there.
You now have your CentOS officially supported gcc and g++ still in /usr/bin/, your CentOS officially supported 32-bit libs in /lib, your CentOS officially supported 64-bit libs in /lib64, and your CentOS officially supported include files in /usr/include.
Your newer gcc and g++ are in /usr/local/bin, newer 32-bit libs in /usr/local/lib, your newer 64-bit libs in /usr/local/lib64, and your newer include files in /usr/local/include.