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			3.1 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
		
		
			
		
	
	
			71 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
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								<html lang="en">
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								<head>
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								<title>BFD outline - Untitled</title>
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								<meta http-equiv="Content-Type" content="text/html">
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								<meta name="description" content="Untitled">
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								<meta name="generator" content="makeinfo 4.7">
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								<link title="Top" rel="start" href="index.html#Top">
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								<link rel="up" href="BFD.html#BFD" title="BFD">
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								<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
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								<!--
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								This file documents the GNU linker LD
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								(GNU Binutils)
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								version 2.19.
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								Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000,
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								2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
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								Permission is granted to copy, distribute and/or modify this document
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								under the terms of the GNU Free Documentation License, Version 1.1
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								or any later version published by the Free Software Foundation;
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								with no Invariant Sections, with no Front-Cover Texts, and with no
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								Back-Cover Texts.  A copy of the license is included in the
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								section entitled ``GNU Free Documentation License''.-->
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								<style type="text/css"><!--
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								  pre.display { font-family:inherit }
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								--></style>
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								</head>
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								<body>
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								<div class="node">
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								<p>
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								<a name="BFD-outline"></a>Up: <a rel="up" accesskey="u" href="BFD.html#BFD">BFD</a>
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								<hr><br>
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								</div>
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								<h3 class="section">5.1 How It Works: An Outline of BFD</h3>
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								<p><a name="index-opening-object-files-635"></a><!-- This summary of BFD is shared by the BFD and LD docs. -->
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								When an object file is opened, BFD subroutines automatically determine
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								the format of the input object file.  They then build a descriptor in
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								memory with pointers to routines that will be used to access elements of
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								the object file's data structures.
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								   <p>As different information from the object files is required,
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								BFD reads from different sections of the file and processes them. 
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								For example, a very common operation for the linker is processing symbol
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								tables.  Each BFD back end provides a routine for converting
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								between the object file's representation of symbols and an internal
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								canonical format. When the linker asks for the symbol table of an object
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								file, it calls through a memory pointer to the routine from the
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								relevant BFD back end which reads and converts the table into a canonical
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								form.  The linker then operates upon the canonical form. When the link is
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								finished and the linker writes the output file's symbol table,
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								another BFD back end routine is called to take the newly
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								created symbol table and convert it into the chosen output format.
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								<ul class="menu">
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								<li><a accesskey="1" href="BFD-information-loss.html#BFD-information-loss">BFD information loss</a>: 	Information Loss
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								<li><a accesskey="2" href="Canonical-format.html#Canonical-format">Canonical format</a>: 		The BFD	canonical object-file format
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								</ul>
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								   </body></html>
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