&gt; It&#x27;s done because it allows the compiler to generate better, faster code.<p>Why? Why is this OK? You say doing &quot;something reasonable&quot; is hard, but it obviously doesn&#x27;t include entirely ignoring code I wrote. That&#x27;s basically saying &quot;I see you did something weird there, but going to assume the rest of your code and ask the libraries you link to are perfectly standard-compliant, which lets me generate faster code here. I&#x27;m so smart!&quot;<p>Default safe, not fast, wherever possible.