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<h5 class="subsubsection">3.2.5.3 Disadvantages of <code>alloca</code></h5>

<p><a name="index-g_t_0040code_007balloca_007d-disadvantages-347"></a><a name="index-disadvantages-of-_0040code_007balloca_007d-348"></a>These are the disadvantages of <code>alloca</code> in comparison with
<code>malloc</code>:

     <ul>
<li>If you try to allocate more memory than the machine can provide, you
don't get a clean error message.  Instead you get a fatal signal like
the one you would get from an infinite recursion; probably a
segmentation violation (see <a href="Program-Error-Signals.html#Program-Error-Signals">Program Error Signals</a>).

     <li>Some non-GNU systems fail to support <code>alloca</code>, so it is less
portable.  However, a slower emulation of <code>alloca</code> written in C
is available for use on systems with this deficiency. 
</ul>

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