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| <a name="Incomplete-enum-Types"></a> |
| <h3 class="section">6.45 Incomplete <code>enum</code> Types</h3> |
| |
| <p>You can define an <code>enum</code> tag without specifying its possible values. |
| This results in an incomplete type, much like what you get if you write |
| <code>struct foo</code> without describing the elements. A later declaration |
| that does specify the possible values completes the type. |
| </p> |
| <p>You can’t allocate variables or storage using the type while it is |
| incomplete. However, you can work with pointers to that type. |
| </p> |
| <p>This extension may not be very useful, but it makes the handling of |
| <code>enum</code> more consistent with the way <code>struct</code> and <code>union</code> |
| are handled. |
| </p> |
| <p>This extension is not supported by GNU C++. |
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