lfs-book/chapter06/aboutdebug.xml

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<sect1 id="ch-system-aboutdebug">
<title>About Debugging Symbols</title>
<?dbhtml filename="aboutdebug.html"?>

<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
included, 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 bash binary 
with debugging symbols: 1200 KB</para></listitem>

<listitem><para>a bash 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. Additional information on system
optimization can be found at <ulink url="&hints-root;optimization.txt"/>.</para>

</sect1>