title: NSOpenGL profile version 3_2Core
body: <p>When I add NSOpenGLProfileVersion3_2Core to the attributes pixelformat variable is nil, but when i remove it pixel format gets allocated. I dont get what is the problem : (</p>
  
  <pre><code>GLuint attributes[] = {
          NSOpenGLProfileVersionLegacy,
          NSOpenGLProfileVersion3_2Core,
          NSOpenGLPFAWindow,
          NSOpenGLPFAColorSize, 24,
          NSOpenGLPFAAlphaSize, 8,
          NSOpenGLPFAAccelerated,
          NSOpenGLPFADoubleBuffer,
          0
      };
      _pixelformat = [[NSOpenGLPixelFormat alloc]
                      initWithAttributes:
                      (NSOpenGLPixelFormatAttribute *) attributes];
      if (_pixelformat == nil){
          NSLog(@"No valid OpenGL pixel format");
          exit(0);
      }
      NSLog(@"Have a valid pixel format");
  </code></pre>
  
  <p>The result is "No valid OpenGL pixel format."</p>