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| <h3 class="section">6.10 Additional Floating Types</h3> |
| |
| <p><a name="index-additional-floating-types-2227"></a><a name="index-g_t_0040code_007b_005f_005ffloat80_007d-data-type-2228"></a><a name="index-g_t_0040code_007b_005f_005ffloat128_007d-data-type-2229"></a><a name="index-g_t_0040code_007bw_007d-floating-point-suffix-2230"></a><a name="index-g_t_0040code_007bq_007d-floating-point-suffix-2231"></a><a name="index-g_t_0040code_007bW_007d-floating-point-suffix-2232"></a><a name="index-g_t_0040code_007bQ_007d-floating-point-suffix-2233"></a> |
| As an extension, the GNU C compiler supports additional floating |
| types, <code>__float80</code> and <code>__float128</code> to support 80bit |
| (<code>XFmode</code>) and 128 bit (<code>TFmode</code>) floating types. |
| Support for additional types includes the arithmetic operators: |
| add, subtract, multiply, divide; unary arithmetic operators; |
| relational operators; equality operators; and conversions to and from |
| integer and other floating types. Use a suffix ‘<samp><span class="samp">w</span></samp>’ or ‘<samp><span class="samp">W</span></samp>’ |
| in a literal constant of type <code>__float80</code> and ‘<samp><span class="samp">q</span></samp>’ or ‘<samp><span class="samp">Q</span></samp>’ |
| for <code>_float128</code>. You can declare complex types using the |
| corresponding internal complex type, <code>XCmode</code> for <code>__float80</code> |
| type and <code>TCmode</code> for <code>__float128</code> type: |
| |
| <pre class="smallexample"> typedef _Complex float __attribute__((mode(TC))) _Complex128; |
| typedef _Complex float __attribute__((mode(XC))) _Complex80; |
| </pre> |
| <p>Not all targets support additional floating point types. <code>__float80</code> |
| and <code>__float128</code> types are supported on i386, x86_64 and ia64 targets. |
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