Required reading here is Chris Lattner&#x27;s &quot;What Every C&#x2F;C++ Programmer Should Know About Undefined Behavior&quot;, which goes into good detail as to why undefined behavior is important for performance, sometimes very important:  <a href="http:&#x2F;&#x2F;blog.llvm.org&#x2F;2011&#x2F;05&#x2F;what-every-c-programmer-should-know.html?m=1" rel="nofollow">http:&#x2F;&#x2F;blog.llvm.org&#x2F;2011&#x2F;05&#x2F;what-every-c-programmer-should-...</a><p>Could you make a new language that doesn&#x27;t depend on UB for performance? Sure, quite possibly. Is C that language? Probably not.