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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-1511"></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 ‘<samp><span class="samp">-msoft-float</span></samp>’
has been used the module will be marked as soft-float. If
‘<samp><span class="samp">-msingle-float</span></samp>’ 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 ‘<samp><span class="samp">-mfpxx</span></samp>’,
‘<samp><span class="samp">-mfp64</span></samp>’ and ‘<samp><span class="samp">-mno-odd-spreg</span></samp>’.
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