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Node:<a name="Output%20Section%20Address">Output Section Address</a>,

Next:<a rel="next" accesskey="n" href="Input-Section.html#Input%20Section">Input Section</a>,

Previous:<a rel="previous" accesskey="p" href="Output-Section-Name.html#Output%20Section%20Name">Output Section Name</a>,

Up:<a rel="up" accesskey="u" href="SECTIONS.html#SECTIONS">SECTIONS</a>

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<h4 class="subsection">Output section address</h4>



   <p>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>and

<pre class="smallexample">     .text : { *(.text) }

     </pre>



<p>are subtly different.  The first will set the address of the

<code>.text</code> 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 <code>.text</code> 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>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.



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