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			95 lines
		
	
	
	
		
			4.2 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
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								<html lang="en">
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								<title>Linker Functions - Untitled</title>
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								<link rel="up" href="BFD-front-end.html#BFD-front-end" title="BFD front end">
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								<!--
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								This file documents the BFD library.
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								Copyright (C) 1991, 2000, 2001, 2003, 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 or
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								any later version published by the Free Software Foundation; with the
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								Invariant Sections being ``GNU General Public License'' and ``Funding
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								Free Software'', the Front-Cover texts being (a) (see below), and with
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								the Back-Cover Texts being (b) (see below).  A copy of the license is
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								included in the section entitled ``GNU Free Documentation License''.
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								(a) The FSF's Front-Cover Text is:
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								     A GNU Manual
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								(b) The FSF's Back-Cover Text is:
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								     You have freedom to copy and modify this GNU Manual, like GNU
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								     software.  Copies published by the Free Software Foundation raise
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								     funds for GNU development.-->
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								<p>
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								<a name="Linker-Functions"></a>Next: <a rel="next" accesskey="n" href="Hash-Tables.html#Hash-Tables">Hash Tables</a>,
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								Previous: <a rel="previous" accesskey="p" href="File-Caching.html#File-Caching">File Caching</a>,
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								Up: <a rel="up" accesskey="u" href="BFD-front-end.html#BFD-front-end">BFD front end</a>
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								<hr><br>
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								</div>
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								<h3 class="section">2.17 Linker Functions</h3>
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								<p><a name="index-Linker-1368"></a>The linker uses three special entry points in the BFD target
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								vector.  It is not necessary to write special routines for
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								these entry points when creating a new BFD back end, since
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								generic versions are provided.  However, writing them can
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								speed up linking and make it use significantly less runtime
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								memory.
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								   <p>The first routine creates a hash table used by the other
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								routines.  The second routine adds the symbols from an object
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								file to the hash table.  The third routine takes all the
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								object files and links them together to create the output
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								file.  These routines are designed so that the linker proper
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								does not need to know anything about the symbols in the object
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								files that it is linking.  The linker merely arranges the
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								sections as directed by the linker script and lets BFD handle
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								the details of symbols and relocs.
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								   <p>The second routine and third routines are passed a pointer to
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								a <code>struct bfd_link_info</code> structure (defined in
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								<code>bfdlink.h</code>) which holds information relevant to the link,
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								including the linker hash table (which was created by the
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								first routine) and a set of callback functions to the linker
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								proper.
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								   <p>The generic linker routines are in <code>linker.c</code>, and use the
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								header file <code>genlink.h</code>.  As of this writing, the only back
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								ends which have implemented versions of these routines are
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								a.out (in <code>aoutx.h</code>) and ECOFF (in <code>ecoff.c</code>).  The a.out
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								routines are used as examples throughout this section.
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								<ul class="menu">
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								<li><a accesskey="1" href="Creating-a-Linker-Hash-Table.html#Creating-a-Linker-Hash-Table">Creating a Linker Hash Table</a>
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								<li><a accesskey="2" href="Adding-Symbols-to-the-Hash-Table.html#Adding-Symbols-to-the-Hash-Table">Adding Symbols to the Hash Table</a>
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								<li><a accesskey="3" href="Performing-the-Final-Link.html#Performing-the-Final-Link">Performing the Final Link</a>
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								</ul>
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