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<title>Using the GNU Compiler Collection (GCC): Enumerator Attributes</title>

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<a name="Enumerator-Attributes"></a>
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Next: <a href="Statement-Attributes.html#Statement-Attributes" accesskey="n" rel="next">Statement Attributes</a>, Previous: <a href="Label-Attributes.html#Label-Attributes" accesskey="p" rel="prev">Label Attributes</a>, Up: <a href="C-Extensions.html#C-Extensions" accesskey="u" rel="up">C Extensions</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Enumerator-Attributes-1"></a>
<h3 class="section">6.35 Enumerator Attributes</h3>
<a name="index-Enumerator-Attributes"></a>

<p>GCC allows attributes to be set on enumerators.  See <a href="Attribute-Syntax.html#Attribute-Syntax">Attribute Syntax</a>, for
details of the exact syntax for using attributes.  Other attributes are
available for functions (see <a href="Function-Attributes.html#Function-Attributes">Function Attributes</a>), variables
(see <a href="Variable-Attributes.html#Variable-Attributes">Variable Attributes</a>), labels (see <a href="Label-Attributes.html#Label-Attributes">Label Attributes</a>), statements
(see <a href="Statement-Attributes.html#Statement-Attributes">Statement Attributes</a>), and for types (see <a href="Type-Attributes.html#Type-Attributes">Type Attributes</a>).
</p>
<p>This example uses the <code>deprecated</code> enumerator attribute to indicate the
<code>oldval</code> enumerator is deprecated:
</p>
<div class="smallexample">
<pre class="smallexample">enum E {
  oldval __attribute__((deprecated)),
  newval
};

int
fn (void)
{
  return oldval;
}
</pre></div>

<dl compact="compact">
<dt><code>deprecated</code></dt>
<dd><a name="index-deprecated-enumerator-attribute"></a>
<p>The <code>deprecated</code> attribute results in a warning if the enumerator
is used anywhere in the source file.  This is useful when identifying
enumerators that are expected to be removed in a future version of a
program.  The warning also includes the location of the declaration
of the deprecated enumerator, to enable users to easily find further
information about why the enumerator is deprecated, or what they should
do instead.  Note that the warnings only occurs for uses.
</p>
</dd>
</dl>


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