I&#x27;ve seen a lot of weird preprocessor (ab)use in GNU code. The coreutils true&#x2F;false (of all programs to invoke clever preprocessor tricks...) has this gem:<p>in true.c (all told, an 80-line file):<p><pre><code>  &#x2F;* Act like &quot;true&quot; by default; false.c overrides this.  *&#x2F;
  #ifndef EXIT_STATUS
  # define EXIT_STATUS EXIT_SUCCESS
  #endif
</code></pre>
false.c, of course, contains only:<p><pre><code>  #define EXIT_STATUS EXIT_FAILURE
  #include &quot;true.c&quot;
</code></pre>
On my current system, each of these represents a stately 27KB <i>dynamically linked</i> executable.<p>By way of comparison, the OpenBSD version of true comprises nine lines with zero preprocessor directives:<p><pre><code>  &#x2F;*	$OpenBSD: true.c,v 1.1 2015&#x2F;11&#x2F;11 19:05:28 deraadt Exp $	*&#x2F;

  &#x2F;* Public domain - Theo de Raadt *&#x2F;

  int
  main(int argc, char *argv[])
  {
  	return (0);
  }</code></pre>