| 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>About Debugging Symbols</title>
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| 12 |
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| 13 | <para>Most programs and libraries are, by default, compiled with
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| 14 | debugging symbols included (with <command>gcc</command>'s
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| 15 | <parameter>-g</parameter> option). This means that when debugging a
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| 16 | program or library that was compiled with debugging information
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| 17 | included, the debugger can provide not only memory addresses, but also
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| 18 | the names of the routines and variables.</para>
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| 19 |
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| 20 | <para>However, the inclusion of these debugging symbols enlarges a
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| 21 | program or library significantly. The following is an example of the
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| 22 | amount of space these symbols occupy:</para>
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| 23 |
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| 24 | <itemizedlist>
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| 25 | <listitem>
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| 26 | <para>A <command>bash</command> binary with debugging symbols:
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| 27 | 1200 KB</para>
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| 28 | </listitem>
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| 29 | <listitem>
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| 30 | <para>A <command>bash</command> binary without debugging symbols:
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| 31 | 480 KB</para>
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| 32 | </listitem>
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| 33 | <listitem>
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| 34 | <para>Glibc and GCC files (<filename class="directory">/lib</filename>
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| 35 | and <filename class="directory">/usr/lib</filename>) with debugging
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| 36 | symbols: 87 MB</para>
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| 37 | </listitem>
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| 38 | <listitem>
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| 39 | <para>Glibc and GCC files without debugging symbols: 16 MB</para>
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| 40 | </listitem>
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| 41 | </itemizedlist>
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| 42 |
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| 43 | <para>Sizes may vary depending on which compiler and C library were used,
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| 44 | but when comparing programs with and without debugging symbols, the
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| 45 | difference will usually be a factor between two and five.</para>
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| 46 |
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| 47 | <para>Because most users will never use a debugger on their system software,
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| 48 | a lot of disk space can be regained by removing these symbols. The next
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| 49 | section shows how to strip all debugging symbols from the programs and
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| 50 | libraries. Additional information on system optimization can be found at
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| 51 | <ulink url="&hints-root;optimization.txt"/>.</para>
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| 52 |
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| 53 | </sect1>
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