message: return NULL earlier.
diff: @@ -248,13 +248,10 @@ static void *PtrAlias(mm::ledger &maps, void *ptr)
  void *mm::Ptr(void *ptr)
  {
  if (MmDeviceIniFilter()) { return ptr; }
  + if (ptr==NULL) { return NULL;};
  if (Known(ptr)) { return PtrKnown(maps, ptr); }
  if (Alias(ptr)) { return PtrAlias(maps, ptr); }
  - if (ptr==NULL)
  - {
  - return NULL;
  - }
  - else
  + if (config::UsingDevice())
  {
  mfem_error("Trying to use unknown pointer on the DEVICE!");
  }
  