# Building 32-bit packages on a 64-bit system

## Build 32-bit packages in a 64-bit environment

Note: devtools is needed. Because of circular dependencies, you may need to install arch-install-scripts at the same time.
Note: If you are using or plan to use either Install bundled 32-bit system in Arch64 you will need to use a different directory other than /opt/arch32 since this tutorial will conflict with the directory chosen in the other articles.

This example uses mkarchroot to create the chroot environment. First, create /opt/arch32 or another directory of your choice. The next steps is to copy your existing pacman.conf and makepkg.conf file to /opt/arch32 or your chosen directory. In the following tutorial, substitute /opt/arch32 with your chosen directory if you decide to use a different directory.

Note: If you have customized either makepkg.conf or pacman.conf, then you will need to use the standard pacman.conf and makepkg.conf files. Also make sure your /etc/pacman.d/mirrorlist contains the $arch variable instead of x86_64 or i686

Edit your /opt/arch32/pacman.conf

Change `Architecture = auto` to `Architecture = i686`.

You will also need to comment out any multi-lib repos.

Note: Thanks to Remy Oudompheng to pointing this out. devtools (version 0.9.10 in [testing]) contains a ready-to-use /usr/share/devtools/makepkg-i686.conf. If you decide to use this conf file, you can skip the next step. You will need to copy /usr/share/devtools/makepkg-i686.conf to /opt/arch32/makepkg.conf if you decide to use devtools[from testing].

Edit /opt/arch32/makepkg.conf

    Change CARCH="x86_64" to CARCH="i686"
    CHOST="x86_64-unknown-linux-gnu" to CHOST="i686-unknown-linux-gnu".
    CFLAGS="-march=x86_64 -mtune=generic -O2 -pipe" to CFLAGS="-march=i686 -mtune=generic -O2 -pipe" .
    CXXFLAGS="-march=x86_64 -mtune=generic -O2 -pipe" to CXXFLAGS="-march=i686 -mtune=generic -O2 -pipe" .

After the changes have been made, you will need to create another directory, I created /aur as mine.

Next run:

    sudo mkarchroot -C /opt/arch32/pacman.conf -M /opt/arch32/makepkg.conf <chrootdir>/root base base-devel

If you create the /aur directory like mine you would run

    sudo mkarchroot -C /opt/arch32/pacman.conf -M /opt/arch32/makepkg.conf /aur/root base base-devel

You will need to edit /aur/copy/etc/pacman.d/mirrorlist and select which mirrors to use.

Now you can use makechrootpkg to build i686 packages like this:

    # makechrootpkg -r /aur/

Category:

- Package development