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| <h4 class="subsection">6.54.9 Weak Pragmas</h4> |
| |
| <p>For compatibility with SVR4, GCC supports a set of <code>#pragma</code> |
| directives for declaring symbols to be weak, and defining weak |
| aliases. |
| |
| <dl> |
| <dt><code>#pragma weak </code><var>symbol</var><dd><a name="index-pragma_002c-weak-3139"></a>This pragma declares <var>symbol</var> to be weak, as if the declaration |
| had the attribute of the same name. The pragma may appear before |
| or after the declaration of <var>symbol</var>, but must appear before |
| either its first use or its definition. It is not an error for |
| <var>symbol</var> to never be defined at all. |
| |
| <br><dt><code>#pragma weak </code><var>symbol1</var><code> = </code><var>symbol2</var><dd>This pragma declares <var>symbol1</var> to be a weak alias of <var>symbol2</var>. |
| It is an error if <var>symbol2</var> is not defined in the current |
| translation unit. |
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