title: emacs compilation cannot find source file in some case ("In file included from")
body: <p>Compilation mode works well with error like this :</p>
  
  <pre><code>./display.h:899:2: warning: multi-line comment [-Wcomment]
  </code></pre>
  
  <p>but it fails with error like this :</p>
  
  <pre><code>In file included from ./internal.h:32:0,                         &lt;-- HERE
                   from world_script/fieldSet.c:33:
  ./display.h:899:2: warning: multi-line comment [-Wcomment]
  </code></pre>
  
  <p>Make has entered a sub-directory and Emacs has noted it because it offers this message in the minibuffer :</p>
  
  <p><strong>Find this error in (default ./internal.h:32): /local/wk/michel/conf/cvs/freewrl/freewrl-HEAD/src/lib</strong></p>
  
  <p>If I make the compilation buffer writable, and I delete the column number to have this line instead :</p>
  
  <pre><code>In file included from ./internal.h:32,
  </code></pre>
  
  <p>then it works.</p>