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<overview>

<p>The <code>free</code> function, which deallocates heap memory, may accept a NULL pointer and take no action. Therefore, it is unnecessary to check the argument for the value of NULL before a function call to <code>free</code>. As such, these guards may hinder performance and readability.</p>

</overview>

<recommendation>

<p>A function call to <code>free</code> should not depend upon the value of its argument. Delete the condition preceding a function call to <code>free</code> when its only purpose is to check the value of the pointer to be freed.</p>

</recommendation>

<example>

<sample src = "GuardedFree.cpp" />

<p>In this example, the condition checking the value of <code>foo</code> can be deleted.</p>

</example>

<references>

<li>

The Open Group Base Specifications Issue 7, 2018 Edition:

<a href="https://pubs.opengroup.org/onlinepubs/9699919799/functions/free.html">free - free allocated memory</a>.

</li>

</references>

</qhelp>