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Next:&nbsp;<a rel="next" accesskey="n" href="MIPS-FP-ABI-Variants.html#MIPS-FP-ABI-Variants">MIPS FP ABI Variants</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="MIPS-FP-ABIs.html#MIPS-FP-ABIs">MIPS FP ABIs</a>
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<h5 class="subsubsection">9.27.9.1 History of FP ABIs</h5>

<p><a name="index-g_t_0040code_007b_002egnu_005fattribute-4_002c-_0040var_007bn_007d_007d-directive_002c-MIPS-1593"></a><a name="index-g_t_0040code_007b_002egnu_005fattribute-Tag_005fGNU_005fMIPS_005fABI_005fFP_002c-_0040var_007bn_007d_007d-directive_002c-MIPS-1594"></a>The MIPS ABIs support a variety of different floating-point extensions
where calling-convention and register sizes vary for floating-point data. 
The extensions exist to support a wide variety of optional architecture
features.  The resulting ABI variants are generally incompatible with each
other and must be tracked carefully.

   <p>Traditionally the use of an explicit <code>.gnu_attribute 4, </code><var>n</var>
directive is used to indicate which ABI is in use by a specific module. 
It was then left to the user to ensure that command-line options and the
selected ABI were compatible with some potential for inconsistencies.

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