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<title>GNU libgomp: Enabling OpenACC</title>

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<a name="Enabling-OpenACC"></a>
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Next: <a href="OpenACC-Runtime-Library-Routines.html#OpenACC-Runtime-Library-Routines" accesskey="n" rel="next">OpenACC Runtime Library Routines</a>, Previous: <a href="Environment-Variables.html#Environment-Variables" accesskey="p" rel="prev">Environment Variables</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Library-Index.html#Library-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Enabling-OpenACC-1"></a>
<h2 class="chapter">4 Enabling OpenACC</h2>

<p>To activate the OpenACC extensions for C/C++ and Fortran, the compile-time 
flag <samp>-fopenacc</samp> must be specified.  This enables the OpenACC directive
<code>#pragma acc</code> in C/C++ and <code>!$accp</code> directives in free form,
<code>c$acc</code>, <code>*$acc</code> and <code>!$acc</code> directives in fixed form,
<code>!$</code> conditional compilation sentinels in free form and <code>c$</code>,
<code>*$</code> and <code>!$</code> sentinels in fixed form, for Fortran.  The flag also
arranges for automatic linking of the OpenACC runtime library 
(<a href="OpenACC-Runtime-Library-Routines.html#OpenACC-Runtime-Library-Routines">OpenACC Runtime Library Routines</a>).
</p>
<p>A complete description of all OpenACC directives accepted may be found in 
the <a href="http://www.openacc.org/">OpenACC</a> Application Programming
Interface manual, version 2.0.
</p>
<p>Note that this is an experimental feature and subject to
change in future versions of GCC.  See
<a href="https://gcc.gnu.org/wiki/OpenACC">https://gcc.gnu.org/wiki/OpenACC</a> for more information.
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