title: boost microsec_time_clock.hpp warning C4244
body: <p>I'm new in using boost and have a problem. I need shared_mutex function in my project. So I've done</p>
  
  <pre><code>#include "boost/thread/shared_mutex.hpp"
  </code></pre>
  
  <p>And compiled my project. My MSVC 2005 with "treat warnings as errors"  stops compilation because of a warning:</p>
  
  <p><code>c:\\...\microsec_time_clock.hpp(103) : warning C4244: 'argument' : conversion from 'int' to 'unsigned short', possible loss of data</code></p>
  
  <p>I have no idea, why shared_mutex needs microseconds function (I've read than boost libraries have rather big dependences list), but i can't compile my project. I've googled a bit, found same problem, but no decision.</p>
  
  <p>UPDATE: I'm compiling boost now, but i want to put all sources to my open-source project, including boost.thread.shared_mutex.</p>