(at least not without direct knowledge of the precise behavior of <code>f</code>):
</p>

<pre>
f()
i := *p
*q = 1
</pre>

<p>
If the call never returned, then once again the original program
would never access <code>*p</code> or <code>*q</code>, but the rewritten program would.
And if the call contained synchronizing operations, then the original program