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<!-- common example(s) for global, local, constant, and private -->
<para>
There is no generic address space name for program scope variables. All program scope
variables must be declared in the <function>__constant</function> address space. For example:
</para>
<informaltable frame="none">
<tgroup cols="1" align="left" colsep="0" rowsep="0">
<colspec colname="col1" colnum="1" />
<tbody>
<row>
<entry>
// declares a pointer p in the __private address space that
// points to an int object in address space __global
__global int *p;
// declares an array of 4 floats in the __private address space.
float x[4];
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>
There is no address space for function return values. Using an address space qualifier in
a function return type declaration will generate a compilation error, unless the return
type is declared as a pointer type and the qualifier is used on the points-to address space.
</para>
<para>
For example:
</para>
<informaltable frame="none">
<tgroup cols="1" align="left" colsep="0" rowsep="0">
<colspec colname="col1" colnum="1" />
<tbody>
<row>
<entry>
__private int f() { ... } // should generate an error
__local int *f() { ... } // allowed
__local int * __private f() { ... }; // should generate an error.
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<!-- 14-Oct-2011 -->
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