Allan McRae wrote:

All Arch Linux packages have had there files in the /lib directory moved to /usr/lib and now /lib is a symlink to usr/lib. When performing this update, pacman will likely identify a conflict in the /lib directory. In the simplest case, this is worked around by doing:

` pacman -Syu --ignore glibc

pacman -Su `

Never use `--force` during this update.

If either of this steps does not work (e.g. due to dependency version issues, file conflicts in /lib), refer to this [guide][1] for more detailed instructions on performing this upgrade.

[1]: https://wiki.archlinux.org/index.php/DeveloperWiki:usrlib

URL: http://www.archlinux.org/news/the-lib-directory-becomes-a-symlink/