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<h5 class="subsubsection">9.27.9.3 Automatic selection of FP ABI</h5>

<p><a name="index-g_t_0040code_007b_002emodule-fp_003d_0040var_007bnn_007d_007d-directive_002c-MIPS-1595"></a>In order to simplify and add safety to the process of selecting the
correct floating-point ABI, the assembler will automatically infer the
correct <code>.gnu_attribute 4, </code><var>n</var> directive based on command-line
options and <code>.module</code> overrides.  Where an explicit
<code>.gnu_attribute 4, </code><var>n</var> directive has been seen then a warning
will be raised if it does not match an inferred setting.

   <p>The floating-point ABI is inferred as follows.  If &lsquo;<samp><span class="samp">-msoft-float</span></samp>&rsquo;
has been used the module will be marked as soft-float.  If
&lsquo;<samp><span class="samp">-msingle-float</span></samp>&rsquo; has been used then the module will be marked as
single-precision.  The remaining ABIs are then selected based
on the FP register width.  Double-precision is selected if the width
of GP and FP registers match and the special double-precision variants
for 32-bit ABIs are then selected depending on &lsquo;<samp><span class="samp">-mfpxx</span></samp>&rsquo;,
&lsquo;<samp><span class="samp">-mfp64</span></samp>&rsquo; and &lsquo;<samp><span class="samp">-mno-odd-spreg</span></samp>&rsquo;.

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