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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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