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<title>Using the GNU Compiler Collection (GCC): RISC-V Function Attributes</title>
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<a name="RISC_002dV-Function-Attributes"></a>
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Next: <a href="RL78-Function-Attributes.html#RL78-Function-Attributes" accesskey="n" rel="next">RL78 Function Attributes</a>, Previous: <a href="PowerPC-Function-Attributes.html#PowerPC-Function-Attributes" accesskey="p" rel="previous">PowerPC Function Attributes</a>, Up: <a href="Function-Attributes.html#Function-Attributes" accesskey="u" rel="up">Function Attributes</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p>
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<a name="RISC_002dV-Function-Attributes-1"></a>
<h4 class="subsection">6.33.25 RISC-V Function Attributes</h4>
<p>These function attributes are supported by the RISC-V back end:
</p>
<dl compact="compact">
<dd><a name="index-naked-function-attribute_002c-RISC_002dV"></a>
</dd>
<dt><code>naked</code></dt>
<dd><p>This attribute allows the compiler to construct the
requisite function declaration, while allowing the body of the
function to be assembly code. The specified function will not have
prologue/epilogue sequences generated by the compiler. Only basic
<code>asm</code> statements can safely be included in naked functions
(see <a href="Basic-Asm.html#Basic-Asm">Basic Asm</a>). While using extended <code>asm</code> or a mixture of
basic <code>asm</code> and C code may appear to work, they cannot be
depended upon to work reliably and are not supported.
</p>
<a name="index-interrupt-function-attribute_002c-RISC_002dV"></a>
</dd>
<dt><code>interrupt</code></dt>
<dd><p>Use this attribute to indicate that the specified function is an interrupt
handler. The compiler generates function entry and exit sequences suitable
for use in an interrupt handler when this attribute is present.
</p>
<p>You can specify the kind of interrupt to be handled by adding an optional
parameter to the interrupt attribute like this:
</p>
<div class="smallexample">
<pre class="smallexample">void f (void) __attribute__ ((interrupt ("user")));
</pre></div>
<p>Permissible values for this parameter are <code>user</code>, <code>supervisor</code>,
and <code>machine</code>. If there is no parameter, then it defaults to
<code>machine</code>.
</p></dd>
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