title: getting ERROR C4013 - __readcr() undefined; assuming extern returning int
body: <p>I'm trying to compile a driver and I'm getting these error:</p>
  
  <pre><code>Error   C2220   warning treated as error - no 'object' file generated
  Error   C4013   '__writecr0' undefined; assuming extern returning int
  Error   C4013   '__readcr0' undefined; assuming extern returning int
  </code></pre>
  
  <p>I've included intrin.h too, solution platform is ARM64</p>
  
  <pre><code>UINT64 cr0 = __readcr0();
  __writecr0( cr0 &amp; 
  *(PUSHORT)place = 
  *(PULONG)(place + 2) = 
  *(PVOID**)(place + 6) = 
  __writecr0( cr0 );
  </code></pre>