The software used to create a CLFS system is constantly being updated and enhanced. Security warnings and bug fixes may become available after the CLFS book has been released. Some host systems may also have problems building CLFS. To check whether the package versions or instructions in this release of CLFS need any modifications to accommodate security vulnerabilities, other bug fixes, or host-specific issues, please visit http://trac.cross-lfs.org/clfs/errata/1.0.0rc4/ before proceeding with your build. You should note any changes shown and apply them to the relevant section of the book as you progress with building the CLFS system.