title: OpenGL: glGetError() returns invalid enum after call to glewInit()
body: <p>I use GLEW and freeglut. For some reason, after a call to glewInit(), glGetError() returns error code 1280, even with glewExperimental = GL_FALSE. </p>
  
  <p>I cannot compile the shaders, glGetProgramInfoLog() returns "Vertex shader(s) were not successfully compiled before glLinkProgram() was called.  Link failed." I was able to compile the shaders before.</p>
  
  <p>Reinstalling the drivers didn't help. </p>
  
  <p>Here's my code: </p>
  
  <pre><code>int main(int argc, char* argv[])
  {
      GLenum GlewInitResult, res;
  
      InitWindow(argc, argv);
  
      res = glGetError(); // res = 0
  
      glewExperimental = GL_TRUE;
      GlewInitResult = glewInit();    
  
      fprintf(stdout, "ERROR: %s\n", glewGetErrorString(GlewInitResult)); // "No error"
      res = glGetError(); // res = 1280
  
      glutMainLoop();
  
      exit(EXIT_SUCCESS);
  }
  
  void InitWindow(int argc, char* argv[])
  {
      glutInit(&amp;argc, argv);
  
      glutInitContextVersion(4, 0);
      glutInitContextFlags(GLUT_FORWARD_COMPATIBLE);
      glutInitContextProfile(GLUT_CORE_PROFILE);
  
      glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE,
      GLUT_ACTION_GLUTMAINLOOP_RETURNS);
  
      glutInitWindowPosition(0, 0);
      glutInitWindowSize(CurrentWidth, CurrentHeight);
      glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
  
      WindowHandle = glutCreateWindow(WINDOW_TITLE);
  
      GLenum errorCheckValue = glGetError();
  
      if (WindowHandle &lt; 1)
      {
          fprintf(stderr, "ERROR: Could not create new rendering window.\n");
          exit(EXIT_FAILURE);
      }
  
      glutReshapeFunc(ResizeFunction);
      glutDisplayFunc(RenderFunction);
      glutIdleFunc(IdleFunction);
      glutTimerFunc(0, TimerFunction, 0);
      glutCloseFunc(Cleanup);
      glutKeyboardFunc(KeyboardFunction);
  }
  </code></pre>
  
  <p>What I am doing wrong?</p>