title: What happens to unused function return values?
body: <p>If I have a program:</p>
  
  <pre><code>#include &lt;iostream&gt;
  
  using namespace std;
  
  int TestIntReturn(int &amp;x, int &amp;y)
  {
      x = 1000;
      y = 1000;
      return x+y;
  }
  
  int main()
  {
      int a = 1;
      int b = 2;
      cout &lt;&lt; a &lt;&lt; " " &lt;&lt; b &lt;&lt; endl;
      TestIntReturn(a,b);
      cout &lt;&lt; a &lt;&lt; " " &lt;&lt; b &lt;&lt; endl;
  }
  </code></pre>
  
  <p>what happens to the return value of <code>TestInReturn(a,b)</code> since it is unused?</p>