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 <a name="Output-Section-Address"></a>
 <div class="header">
 <p>
 Next: <a href="Input-Section.html#Input-Section" accesskey="n" rel="next">Input Section</a>, Previous: <a href="Output-Section-Name.html#Output-Section-Name" accesskey="p" rel="prev">Output Section Name</a>, Up: <a href="SECTIONS.html#SECTIONS" accesskey="u" rel="up">SECTIONS</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
 </div>
 <hr>
 <a name="Output-Section-Address-1"></a>
 <h4 class="subsection">3.6.3 Output Section Address</h4>
 <a name="index-address_002c-section"></a>
 <a name="index-section-address"></a>
 <p>The <var>address</var> is an expression for the VMA (the virtual memory
 address) of the output section.  This address is optional, but if it
 is provided then the output address will be set exactly as specified.
 </p>
 <p>If the output address is not specified then one will be chosen for the
 section, based on the heuristic below.  This address will be adjusted
 to fit the alignment requirement of the output section.  The
 alignment requirement is the strictest alignment of any input section
 contained within the output section.
 </p>
 <p>The output section address heuristic is as follows:
 </p>
 <ul>
 <li> If an output memory <var>region</var> is set for the section then it
 is added to this region and its address will be the next free address
 in that region.

 </li><li> If the MEMORY command has been used to create a list of memory
 regions then the first region which has attributes compatible with the
 section is selected to contain it.  The section&rsquo;s output address will
 be the next free address in that region; <a href="MEMORY.html#MEMORY">MEMORY</a>.

 </li><li> If no memory regions were specified, or none match the section then
 the output address will be based on the current value of the location
 counter.
 </li></ul>

 <p>For example:
 </p>
 <div class="smallexample">
 <pre class="smallexample">.text . : { *(.text) }
 </pre></div>

 <p>and
 </p>
 <div class="smallexample">
 <pre class="smallexample">.text : { *(.text) }
 </pre></div>

 <p>are subtly different.  The first will set the address of the
 &lsquo;<samp>.text</samp>&rsquo; 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 any of the &lsquo;<samp>.text</samp>&rsquo;
 input sections.
 </p>
 <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:
 </p><div class="smallexample">
 <pre class="smallexample">.text ALIGN(0x10) : { *(.text) }
 </pre></div>
 <p>This works because <code>ALIGN</code> returns the current location counter
 aligned upward to the specified value.
 </p>
 <p>Specifying <var>address</var> for a section will change the value of the
 location counter, provided that the section is non-empty.  (Empty
 sections are ignored).
 </p>
 <hr>
 <div class="header">
 <p>
 Next: <a href="Input-Section.html#Input-Section" accesskey="n" rel="next">Input Section</a>, Previous: <a href="Output-Section-Name.html#Output-Section-Name" accesskey="p" rel="prev">Output Section Name</a>, Up: <a href="SECTIONS.html#SECTIONS" accesskey="u" rel="up">SECTIONS</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
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	<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
	<a name="Output-Section-Address"></a>
	<div class="header">
	<p>
	Next: <a href="Input-Section.html#Input-Section" accesskey="n" rel="next">Input Section</a>, Previous: <a href="Output-Section-Name.html#Output-Section-Name" accesskey="p" rel="prev">Output Section Name</a>, Up: <a href="SECTIONS.html#SECTIONS" accesskey="u" rel="up">SECTIONS</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
	</div>
	<hr>
	<a name="Output-Section-Address-1"></a>
	<h4 class="subsection">3.6.3 Output Section Address</h4>
	<a name="index-address_002c-section"></a>
	<a name="index-section-address"></a>
	<p>The <var>address</var> is an expression for the VMA (the virtual memory
	address) of the output section. This address is optional, but if it
	is provided then the output address will be set exactly as specified.
	</p>
	<p>If the output address is not specified then one will be chosen for the
	section, based on the heuristic below. This address will be adjusted
	to fit the alignment requirement of the output section. The
	alignment requirement is the strictest alignment of any input section
	contained within the output section.
	</p>
	<p>The output section address heuristic is as follows:
	</p>
	<ul>
	<li> If an output memory <var>region</var> is set for the section then it
	is added to this region and its address will be the next free address
	in that region.

	</li><li> If the MEMORY command has been used to create a list of memory
	regions then the first region which has attributes compatible with the
	section is selected to contain it. The section’s output address will
	be the next free address in that region; <a href="MEMORY.html#MEMORY">MEMORY</a>.

	</li><li> If no memory regions were specified, or none match the section then
	the output address will be based on the current value of the location
	counter.
	</li></ul>

	<p>For example:
	</p>
	<div class="smallexample">
	<pre class="smallexample">.text . : { *(.text) }
	</pre></div>

	<p>and
	</p>
	<div class="smallexample">
	<pre class="smallexample">.text : { *(.text) }
	</pre></div>

	<p>are subtly different. The first will set the address of the
	‘<samp>.text</samp>’ 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 any of the ‘<samp>.text</samp>’
	input sections.
	</p>
	<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:
	</p><div class="smallexample">
	<pre class="smallexample">.text ALIGN(0x10) : { *(.text) }
	</pre></div>
	<p>This works because <code>ALIGN</code> returns the current location counter
	aligned upward to the specified value.
	</p>
	<p>Specifying <var>address</var> for a section will change the value of the
	location counter, provided that the section is non-empty. (Empty
	sections are ignored).
	</p>
	<hr>
	<div class="header">
	<p>
	Next: <a href="Input-Section.html#Input-Section" accesskey="n" rel="next">Input Section</a>, Previous: <a href="Output-Section-Name.html#Output-Section-Name" accesskey="p" rel="prev">Output Section Name</a>, Up: <a href="SECTIONS.html#SECTIONS" accesskey="u" rel="up">SECTIONS</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
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