In this chapter, we enter the building site and start constructing the CLFS system in earnest. The installation of this software is straightforward. Although in many cases the installation instructions could be made shorter and more generic, we have opted to provide the full instructions for every package to minimize the possibilities for mistakes. The key to learning what makes a Linux system work is to know what each package is used for and why the user (or the system) needs it. For every installed package, a summary of its contents is given, followed by concise descriptions of each program and library the package installed.
        If using compiler optimizations, please review the optimization hint
        at http://hints.cross-lfs.org/index.php/Optimization.
        Compiler optimizations can make a program run slightly faster, but
        they may also cause compilation difficulties and problems when
        running the program. If a package refuses to compile when using
        optimization, try to compile it without optimization and see if that
        fixes the problem. Even if the package does compile when using
        optimization, there is the risk it may have been compiled incorrectly
        because of the complex interactions between the code and build tools.
        Also note that the -march and
        -mtune options may cause problems with
        the toolchain packages (Binutils, GCC and Glibc). The small potential
        gains achieved in using compiler optimizations are often outweighed
        by the risks. First-time builders of CLFS are encouraged to build
        without custom optimizations. The subsequent system will still run
        very fast and be stable at the same time.
      
        The order that packages are installed in this chapter needs to be
        strictly followed to ensure that no program accidentally acquires a
        path referring to /tools hard-wired
        into it. For the same reason, do not compile packages in parallel.
        Compiling in parallel may save time (especially on dual-CPU
        machines), but it could result in a program containing a hard-wired
        path to /tools, which will cause the
        program to stop working when that directory is removed.
      
To keep track of which package installs particular files, a package manager can be used. For a general overview of different styles of package managers, please take a look at the next page.