title: Examples of code successfully compiled in C++11 and pre-C++11 that behave differently
body: <p><strong>C++11</strong> brought new keywords and new changes to core aspects of the language.<br>
  So could it be possible to successfully compile the same piece of code in both <strong>C++11</strong> and <strong>pre-C++11</strong>, but get different results from each binary?  By  <strong>pre-C++11</strong>, I'm referring to <strong>C++98</strong>, <strong>C++03</strong>, or <strong>C++TR1</strong>.  </p>
  
  <p>The reason I ask, is because I have a bunch of small programs all written in C++.  I am unaware what standard was in mind for each individual program written.  Is the behaviour of these programs guaranteed to be the same if they all compile in <strong>C++11</strong> as well as an earlier standard?  I would like to compile them all in <strong>C++11</strong>(if they can be), but avoid any subtle changes that may cause the programs to behave differently had an earlier standard been in mind.  </p>
  
  <p>Working examples would be greatly appreciated.  </p>