title: OpenGL access violation on integrated graphics
body: <p>Apologies for the somewhat vague title, but I'm getting a pretty vague bug.</p>
  
  <p>I have a C++ project written in MSVC that uses GLEW and GLFW3 so that I can make use of OpenGL 4.3 compute shaders. The project runs brilliantly on my desktop with an AMD graphics card, however on my laptop with an i5-4300u I get a confusing little exception:</p>
  
  <blockquote>
    <p>Exception thrown at 0x00007FFE99113E4A (ig75icd64.dll) in Examples.exe: 0xC0000005: Access violation reading location 0x0000000000000028.</p>
  </blockquote>
  
  <p>This happens whenever I call <code>glDispatchCompute(x,y,z)</code> followed by <code>glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT)</code>.</p>
  
  <p>GLEW and GLFW definitely both get initialised as I call this code and don't get any ouput:</p>
  
  <pre><code>int glfw_err = glfwInit();
  if (glfw_err == GLFW_FALSE)
  {
      printf("ERROR INITIALIZING GLFW\n");
      glfwTerminate();
      return;
  }
  </code></pre>
  
  <p>and:</p>
  
  <pre><code>GLenum glew_err = glewInit();
  if (glew_err != GLEW_OK) {
      printf("ERROR INITIALIZING GLEW: %s\n", glewGetErrorString(glew_err));
      return;
  }
  </code></pre>
  
  <p><code>ig75icd64.dll</code> mentioned in the exception is an Intel graphics driver library, and I did find some mention of broken drivers online, but reinstalling my drivers doesn't seem to have fixed it.</p>
  
  <p>I'm sure the project did run on my laptop at some point, suggesting that's it's something I've done to break it, but I can't confirm this. The Intel Ark website also says the integrated graphics should support OpenGL 4.3</p>
  
  <p>Any help would be much appreciated! Thank you!</p>