lfs-book/chapter08/aboutdebug.xml

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<sect1 id="ch-system-aboutdebug">
  <?dbhtml filename="aboutdebug.html"?>

  <title>About Debugging Symbols</title>

  <para>Most programs and libraries are, by default, compiled with
  debugging symbols included (with <command>gcc</command>'s
  <parameter>-g</parameter> option). This means that when debugging a
  program or library that was compiled with debugging information,
  the debugger can provide not only memory addresses, but also
  the names of the routines and variables.</para>

  <para>However, the inclusion of these debugging symbols enlarges a
  program or library significantly. The following is an example of the
  amount of space these symbols occupy:</para>

  <itemizedlist>
    <listitem>
      <para>A <command>bash</command> binary with debugging symbols:
      1200 KB</para>
    </listitem>
    <listitem>
      <para>A <command>bash</command> binary without debugging symbols:
      480 KB</para>
    </listitem>
    <listitem>
      <para>Glibc and GCC files (<filename class="directory">/lib</filename>
      and <filename class="directory">/usr/lib</filename>) with debugging
      symbols: 87 MB</para>
    </listitem>
    <listitem>
      <para>Glibc and GCC files without debugging symbols: 16 MB</para>
    </listitem>
  </itemizedlist>

  <para>Sizes may vary depending on which compiler and C library were used,
  but when comparing programs with and without debugging symbols, the
  difference will usually be a factor between two and five.</para>

  <para>Because most users will never use a debugger on their system software,
  a lot of disk space can be regained by removing these symbols. The next
  section shows how to strip all debugging symbols from the programs and
  libraries.</para>

</sect1>