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| <h3 class="section">6.15 Named address spaces</h3> |
| |
| <p><a name="index-named-address-spaces-2283"></a> |
| As an extension, the GNU C compiler supports named address spaces as |
| defined in the N1275 draft of ISO/IEC DTR 18037. Support for named |
| address spaces in GCC will evolve as the draft technical report changes. |
| Calling conventions for any target might also change. At present, only |
| the SPU target supports other address spaces. On the SPU target, for |
| example, variables may be declared as belonging to another address space |
| by qualifying the type with the <code>__ea</code> address space identifier: |
| |
| <pre class="smallexample"> extern int __ea i; |
| </pre> |
| <p>When the variable <code>i</code> is accessed, the compiler will generate |
| special code to access this variable. It may use runtime library |
| support, or generate special machine instructions to access that address |
| space. |
| |
| <p>The <code>__ea</code> identifier may be used exactly like any other C type |
| qualifier (e.g., <code>const</code> or <code>volatile</code>). See the N1275 |
| document for more details. |
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