| 1 | <?xml version="1.0" encoding="ISO-8859-1"?>
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| 2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
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| 3 | <!ENTITY % general-entities SYSTEM "../general.ent">
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| 4 | %general-entities;
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| 5 | ]>
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| 6 | <sect1 id="ch-system-aboutdebug">
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| 7 | <title>About Debugging Symbols</title>
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| 8 | <?dbhtml filename="aboutdebug.html"?>
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| 9 |
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| 10 | <para>Most programs and libraries are, by default, compiled with
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| 11 | debugging symbols included (with <command>gcc</command>'s
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| 12 | <parameter>-g</parameter> option). This means that when debugging a
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| 13 | program or library that was compiled with debugging information
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| 14 | included, the debugger can provide not only memory addresses, but also
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| 15 | the names of the routines and variables.</para>
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| 16 |
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| 17 | <para>However, the inclusion of these debugging symbols enlarges a
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| 18 | program or library significantly. The following is an example of the
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| 19 | amount of space these symbols occupy:</para>
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| 20 |
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| 21 | <itemizedlist>
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| 22 |
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| 23 | <listitem><para>a bash binary
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| 24 | with debugging symbols: 1200 KB</para></listitem>
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| 25 |
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| 26 | <listitem><para>a bash binary
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| 27 | without debugging symbols: 480 KB</para></listitem>
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| 28 |
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| 29 | <listitem><para>Glibc and GCC files (<filename class="directory">/lib</filename>
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| 30 | and <filename class="directory">/usr/lib</filename>)
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| 31 | with debugging symbols: 87 MB</para></listitem>
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| 32 |
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| 33 | <listitem><para>Glibc and GCC files
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| 34 | without debugging symbols: 16 MB</para></listitem>
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| 35 |
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| 36 | </itemizedlist>
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| 37 |
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| 38 | <para>Sizes may vary depending on which compiler and C
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| 39 | library were used, but when comparing programs with and without debugging
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| 40 | symbols, the difference will usually be a factor between two and
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| 41 | five.</para>
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| 42 |
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| 43 | <para>Because most users will never use a debugger on their system
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| 44 | software, a lot of disk space can be regained by removing these
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| 45 | symbols. The next section shows how to strip all debugging symbols
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| 46 | from the programs and libraries. Additional information on system
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| 47 | optimization can be found at <ulink url="&hints-root;optimization.txt"><phrase
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| 48 | condition="pdf">&hints-root; optimization.txt</phrase></ulink>.</para>
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| 49 |
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| 50 | </sect1>
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| 51 |
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