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| <h3 class="section">4.14 Library functions</h3> |
| |
| <p>The behavior of most of these points are dependent on the implementation |
| of the C library, and are not defined by GCC itself. |
| |
| <ul> |
| <li><cite>The null pointer constant to which the macro </cite><code>NULL</code><cite> expands |
| (C90 7.1.6, C99 7.17).</cite> |
| |
| <p>In <code><stddef.h></code>, <code>NULL</code> expands to <code>((void *)0)</code>. GCC |
| does not provide the other headers which define <code>NULL</code> and some |
| library implementations may use other definitions in those headers. |
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