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<title>Using as: MIPS FP ABI Compatibility</title>

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<a name="MIPS-FP-ABI-Compatibility"></a>
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Previous: <a href="MIPS-FP-ABI-Selection.html#MIPS-FP-ABI-Selection" accesskey="p" rel="prev">MIPS FP ABI Selection</a>, Up: <a href="MIPS-FP-ABIs.html#MIPS-FP-ABIs" accesskey="u" rel="up">MIPS FP ABIs</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Linking-different-FP-ABI-variants"></a>
<h4 class="subsubsection">9.27.9.4 Linking different FP ABI variants</h4>
<p>Modules using the default FP ABI (no floating-point) can be linked with
any other (singular) FP ABI variant.
</p>
<p>Special compatibility support exists for O32 with the four
double-precision FP ABI variants.  The &lsquo;<samp>-mfpxx</samp>&rsquo; FP ABI is specifically
designed to be compatible with the standard double-precision ABI and the
&lsquo;<samp>-mfp64</samp>&rsquo; FP ABIs.  This makes it desirable for O32 modules to be
built as &lsquo;<samp>-mfpxx</samp>&rsquo; to ensure the maximum compatibility with other
modules produced for more specific needs.  The only FP ABIs which cannot
be linked together are the standard double-precision ABI and the full
&lsquo;<samp>-mfp64</samp>&rsquo; ABI with &lsquo;<samp>-modd-spreg</samp>&rsquo;.
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