<html lang="en">
<head>
<title>Output Section Address - Untitled</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Untitled">
<meta name="generator" content="makeinfo 4.7">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="SECTIONS.html#SECTIONS" title="SECTIONS">
<link rel="prev" href="Output-Section-Name.html#Output-Section-Name" title="Output Section Name">
<link rel="next" href="Input-Section.html#Input-Section" title="Input Section">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
This file documents the GNU linker LD
(GNU Binutils)
version 2.19.
Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000,
2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1
or any later version published by the Free Software Foundation;
with no Invariant Sections, with no Front-Cover Texts, and with no
Back-Cover Texts. A copy of the license is included in the
section entitled ``GNU Free Documentation License''.-->
<meta http-equiv="Content-Style-Type" content="text/css">
<style type="text/css"><!--
pre.display { font-family:inherit }
pre.format { font-family:inherit }
pre.smalldisplay { font-family:inherit; font-size:smaller }
pre.smallformat { font-family:inherit; font-size:smaller }
pre.smallexample { font-size:smaller }
pre.smalllisp { font-size:smaller }
span.sc { font-variant:small-caps }
span.roman { font-family: serif; font-weight: normal; }
--></style>
</head>
<body>
<div class="node">
<p>
<a name="Output-Section-Address"></a>Next: <a rel="next" accesskey="n" href="Input-Section.html#Input-Section">Input Section</a>,
Previous: <a rel="previous" accesskey="p" href="Output-Section-Name.html#Output-Section-Name">Output Section Name</a>,
Up: <a rel="up" accesskey="u" href="SECTIONS.html#SECTIONS">SECTIONS</a>
<hr><br>
</div>
<h4 class="subsection">3.6.3 Output Section Address</h4>
<p><a name="index-address_002c-section-364"></a><a name="index-section-address-365"></a>The <var>address</var> is an expression for the VMA (the virtual memory
address) of the output section. If you do not provide <var>address</var>,
the linker will set it based on <var>region</var> if present, or otherwise
based on the current value of the location counter.
<p>If you provide <var>address</var>, the address of the output section will be
set to precisely that. If you provide neither <var>address</var> nor
<var>region</var>, then the address of the output section will be set to the
current value of the location counter aligned to the alignment
requirements of the output section. The alignment requirement of the
output section is the strictest alignment of any input section contained
within the output section.
<p>For example,
<pre class="smallexample"> .text . : { *(.text) }
</pre>
<p class="noindent">and
<pre class="smallexample"> .text : { *(.text) }
</pre>
<p class="noindent">are subtly different. The first will set the address of the
<span class="samp">.text</span> output section to the current value of the location
counter. The second will set it to the current value of the location
counter aligned to the strictest alignment of a <span class="samp">.text</span> input
section.
<p>The <var>address</var> may be an arbitrary expression; <a href="Expressions.html#Expressions">Expressions</a>.
For example, if you want to align the section on a 0x10 byte boundary,
so that the lowest four bits of the section address are zero, you could
do something like this:
<pre class="smallexample"> .text ALIGN(0x10) : { *(.text) }
</pre>
<p class="noindent">This works because <code>ALIGN</code> returns the current location counter
aligned upward to the specified value.
<p>Specifying <var>address</var> for a section will change the value of the
location counter.
</body></html>