title: Anyway to see list of preprocessor defined macros?
body: <p>I'd like to see all macros that are defined by the invocation of the compiler I'm using.  Is there any way to do this?   I have seen in the manual it says you can use <code>cpp -dM</code>  but this doesn't work for me. Perhaps I'm doing something wrong?</p>
  
  <p>When I run:</p>
  
  <pre><code>cpp -dM
  </code></pre>
  
  <p>I get no output at all from the preprocessor.  If I try adding <code>-dM</code> as an option on gcc, I don't notice any difference.</p>