title: C++ imported library not compiled correctly
body: <p>I've included the headers of a static library (taglib.a to parse music files on the file system) in my Xcode project).</p>
  
  <p>The library is written in C++. It seems the compiler in Xcode believes it's an objective-C library instead.</p>
  
  <p>I get this compile error in the included header: taglib.h</p>
  
  <pre><code>Unknown type name 'namespace'
  </code></pre>
  
  <p>Usually for this kind of problem the solution is change the extension of the file to .mm to inform the compiler is not only objective-C, but in this case it's an header. And it's the header of an imported library, not even in my project tree.</p>
  
  <p>How to solve this?</p>
  
  <p><img src="https://i.stack.imgur.com/XYaJE.png" alt="enter image description here"></p>
  
  <p>File using the library (#import "taglib/taglib.h")</p>
  
  <p><img src="https://i.stack.imgur.com/A4H7o.png" alt="enter image description here"></p>