title: Does using `__DATE__` or `__TIME__` violate the one-definition-rule?
body: <p>When using <code>__DATE__</code> or <code>__TIME__</code> in a header file, the results of the preprocessor for that header inclusion can be somewhat different. </p>
  
  <p>Under which circumstances does using <code>__DATE__</code> or <code>__TIME__</code> in a header file violate the one-definition-rule? </p>
  
  <p>As a follow-up: Does the <code>assert</code> header violate the one-definition-rule?</p>