title: Multiple #define within #ifdef or #ifndef
body: <p>This is a simple question, but I have not ran across similar code before to know the answer. Basically, am I allowed to have more than two #define in an #ifdef or #ifndef statement? For a basic example:</p>
  
  <pre><code>    #ifdef __GNUC__
          #define HELLO(x) x
          #define WORLD(y) y
      #else
          #define __attribute__(x)
          #define expect(expression, value) (expression)
      #endif
  </code></pre>
  
  <p>Thank you</p>