# Installing GCC without Root Privileges

Posted on November 24, 2015

How do you install or update gcc/g++ without root priviliges (i.e. you can’t just sudo apt-get install)?

A good set of instructions can be found here. But, I’ll add on a little more here. You need to

• the source for gcc will also include the source for g++
• configure
• make
• make install

First, you need to download the source from a gcc mirror. Simply google gcc source download. For instance, you can go here and download the gcc-5.2.0.tar.gz file. You are downloading the tar file which ends with .tar.gz. This contains the source files for gcc 5.2. If you need a different version of gcc, you can search for it.

After donwloading the source, unpack it, and cd into the directory where your version of gcc was unpacked. Then, enter the following commands, replacing all instances of gcc-5.2.0 with your gcc version. Also, this script will install gcc in your home directory. If you want it installed somewhere else, change the prefix option accordingly. The make command could take as little as 2 hours and as much as a day, depending on your system.

tar xzf gcc-5.2.0.tar.gz
cd gcc-5.2.0
cd ..
mkdir objdir
cd objdir
$PWD/../gcc-5.2.0/configure --prefix=$HOME/gcc-5.2.0 --enable-languages=c,c++,fortran,go
make
make install


Now gcc and g++ will be installed on your system. If you would like to use the installed version of gcc (in this casegcc-5.2.0 overthe preinstalled gcc, you can simply add

export PATH=~/gcc-5.2.0/bin:$PATH export LD_LIBRARY_PATH=~/gcc-5.2.0/lib:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=~/gcc-5.2.0/lib64:\$LD_LIBRARY_PATH


to your ~/.bashrc.

For R users, if you need a particular version of gcc to run certain packages (like RcppArmadillo), you can do so by adding

CXX = ~/gcc-5.2.0/bin/g++


to your ~/.R/Makevars file (or creating the file if it does not yet exist).