| 1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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| 2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
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| 3 |   "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
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| 4 |   <!ENTITY % general-entities SYSTEM "../../general.ent">
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| 5 |   %general-entities;
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| 6 | ]>
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| 7 | 
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| 8 | <sect1 id="ch-system-aboutdebug">
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| 9 |   <?dbhtml filename="aboutdebug.html"?>
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| 10 | 
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| 11 |   <title os="a">About Debugging Symbols</title>
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| 12 | 
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| 13 |   <para>Most programs and libraries are, by default, compiled with debugging
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| 14 |   symbols included (with <command>gcc</command>'s <option>-g</option> option).
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| 15 |   This means that when debugging a program or library that was compiled with
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| 16 |   debugging information included, the debugger can provide not only memory
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| 17 |   addresses, but also the names of the routines and variables.</para>
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| 18 | 
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| 19 |   <para os="b">However, the inclusion of these debugging symbols enlarges a
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| 20 |   program or library significantly. The following is an example of the
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| 21 |   amount of space these symbols occupy:</para>
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| 22 | 
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| 23 |   <itemizedlist os="c">
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| 24 |     <listitem>
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| 25 |       <para>a bash binary with debugging symbols: 1200 KB</para>
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| 26 |     </listitem>
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| 27 |     <listitem>
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| 28 |       <para>a bash binary without debugging symbols: 480 KB</para>
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| 29 |     </listitem>
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| 30 |     <listitem>
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| 31 |       <para>Glibc and GCC files (<filename class="directory">/lib</filename>
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| 32 |       and <filename class="directory">/usr/lib</filename>) with debugging
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| 33 |       symbols: 87 MB</para>
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| 34 |     </listitem>
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| 35 |     <listitem>
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| 36 |       <para>Glibc and GCC files without debugging symbols: 16 MB</para>
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| 37 |     </listitem>
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| 38 |   </itemizedlist>
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| 39 | 
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| 40 |   <para os="d">Sizes may vary depending on which compiler and C library were used,
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| 41 |   but when comparing programs with and without debugging symbols, the
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| 42 |   difference will usually be a factor between two and five.</para>
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| 43 | 
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| 44 |   <para os="e">Because most users will never use a debugger on their system software,
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| 45 |   a lot of disk space can be regained by removing these symbols. The next
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| 46 |   section shows how to strip all debugging symbols from the programs and
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| 47 |   libraries. Additional information on system optimization can be found at
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| 48 |   <ulink url="&hints-root;optimization.txt"/>.</para>
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| 49 | 
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| 50 | </sect1>
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