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<h4 class="subsection">3.5.1 Simple Assignments</h4>

<p>You may assign to a symbol using any of the C assignment operators:

     <dl>
<dt><var>symbol</var><code> = </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> += </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> -= </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> *= </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> /= </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> &lt;&lt;= </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> &gt;&gt;= </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> &amp;= </code><var>expression</var><code> ;</code><dt><var>symbol</var><code> |= </code><var>expression</var><code> ;</code><dd></dl>

   <p>The first case will define <var>symbol</var> to the value of
<var>expression</var>.  In the other cases, <var>symbol</var> must already be
defined, and the value will be adjusted accordingly.

   <p>The special symbol name &lsquo;<samp><span class="samp">.</span></samp>&rsquo; indicates the location counter.  You
may only use this within a <code>SECTIONS</code> command.  See <a href="Location-Counter.html#Location-Counter">Location Counter</a>.

   <p>The semicolon after <var>expression</var> is required.

   <p>Expressions are defined below; see <a href="Expressions.html#Expressions">Expressions</a>.

   <p>You may write symbol assignments as commands in their own right, or as
statements within a <code>SECTIONS</code> command, or as part of an output
section description in a <code>SECTIONS</code> command.

   <p>The section of the symbol will be set from the section of the
expression; for more information, see <a href="Expression-Section.html#Expression-Section">Expression Section</a>.

   <p>Here is an example showing the three different places that symbol
assignments may be used:

<pre class="smallexample">     floating_point = 0;
     SECTIONS
     {
       .text :
         {
           *(.text)
           _etext = .;
         }
       _bdata = (. + 3) &amp; ~ 3;
       .data : { *(.data) }
     }
</pre>
   <p class="noindent">In this example, the symbol &lsquo;<samp><span class="samp">floating_point</span></samp>&rsquo; will be defined as
zero.  The symbol &lsquo;<samp><span class="samp">_etext</span></samp>&rsquo; will be defined as the address following
the last &lsquo;<samp><span class="samp">.text</span></samp>&rsquo; input section.  The symbol &lsquo;<samp><span class="samp">_bdata</span></samp>&rsquo; will be
defined as the address following the &lsquo;<samp><span class="samp">.text</span></samp>&rsquo; output section aligned
upward to a 4 byte boundary.

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