title: When should I rerun cmake?
body: <p>After running the <code>cmake</code> command once to generate a build system, when, if ever, should I rerun the <code>cmake</code> command?</p>
  
  <p>The generated build systems can detect changes in the associated <code>CMakeLists.txt</code> files and behave accordingly. You can see the logic for doing so in generated Makefiles. The exact rules for when this will happen successfully are mysterious to me.</p>
  
  <p>When should I rerun <code>cmake</code>? Does the answer depend on the generator used?</p>
  
  <p><a href="http://voices.canonical.com/jussi.pakkanen/2013/03/26/a-list-of-common-cmake-antipatterns/">This blog post</a> (under heading: "Invoking CMake multiple times") points out the confusion over this issue and states that the answer is actually 'never', regardless of generator, but I find that surprising. Is it true?</p>