title: multiple lines macro in C
body: <p>does anyone know why this is syntactically wrong?
  Im trying to covert this</p>
  
  <pre><code>    #define OUTS_FROM_FP(_fp, _argCount) ((u4*) ((u1*)SAVEAREA_FROM_FP(_fp) - sizeof(u4) * (_argCount)))
  </code></pre>
  
  <p>to this</p>
  
  <pre><code>    #define OUTS_FROM_FP(_fp, _argCount) {\
      ((u4*) ((u1*)SAVEAREA_FROM_FP(_fp) - sizeof(u4) * (_argCount))); \
      cout&lt;&lt;"Hello World"&lt;&lt;endl;  \
      }
  
      outs = OUTS_FROM_FP(fp, vsrc1); --this is how it is being called
  </code></pre>
  
  <p>I get a lot of errors when running this: they start from statements that say that variables that were passed to the macro before are unused</p>