title: CUDA __syncthreads() compiles fine but is underlined with red
body: <p>I have been working with CUDA 4.2 for a week now and I have a little problem.
  When I write the __syncthreads() function it becomes underlined and looks like it is wrong...</p>
  
  <p>Then if I put the mouse on the function it appears a message writing: </p>
  
  <blockquote>
    <p>identifier __syncthreads(); is undefined.</p>
  </blockquote>
  
  <p>but when i compile my project the output form build says:</p>
  
  <blockquote>
    <p>========== Build: 1 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========</p>
  </blockquote>
  
  <p>So I am guessing that everything works fine but the fact that Visual Studio underlines the function is confusing me...How can I make Visual studio to know that this function is defined before the compiling process?</p>
  
  <p>NOTE:The same thing happens with the kernel call: kernel&lt;&lt;&lt;...,...>>> where the third "&lt;" is underlined red too...</p>
  
  <p>I know that this probably is a minor problem but i want to solve it...Thanks a lot!
  I am using Visual Studio 2010 on win7 with Cuda 4.2 and Nsight 2.2</p>