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Next: <a rel="next" accesskey="n" href="MIPS-FP-ABI-Variants.html#MIPS-FP-ABI-Variants">MIPS FP ABI Variants</a>,
Up: <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-1509"></a><a name="index-g_t_0040code_007b_002egnu_005fattribute-Tag_005fGNU_005fMIPS_005fABI_005fFP_002c-_0040var_007bn_007d_007d-directive_002c-MIPS-1510"></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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