Compile older compiler (gcc 4.9) on Arch Linux

compile instruction.md

In Arch Linux, you can use the AUR to compile your custom version of GCC (example with gcc 4.9)

[Alternative 1]: using the AUR manually

mkdir -p $HOME/build/
cd $HOME/build/
git clone https://aur.archlinux.org/gcc49.git
cd gcc49
makepkg --syncdeps
sudo pacman --upgrade gcc-4.9.3-1-x86_64.pkg.tar.xz

[Alternative 2]: use one of the available AUR helpers:

example using pacaur (needs to be installed previously)

pacaur -S gcc49

To use the newly installed compiler, you have to set the correct version in the shell you are using:

export CXX=/usr/bin/g++-4.9

Note: this has to be done in each new shell you use. To make it permanent, add the line above to your ~/.bashrc file.

Cool, pacaur saving my day (well, night). Thanks.