Proposed resolution:

This wording is relative to N5008.

1. Modify [range.iter.op.distance] as indicated:

   template<class I, sized_sentinel_for<decay_t<I>> S>
     constexpr iter_difference_t<decay_t<I>> ranges::distance(I&& first, S last);
   

   -3- Effects: Equivalent to:

   if constexpr (!is_array_v<remove_reference_t<I>>)
     return last - first;
   else
     return last - static_cast<const decay_t<I>&>(first);
   

After LWG 3664, `ranges::distance` computes the distance between `last` and `first` by returning last - static_cast<const decay_t<I>&>(first) when the two are subtractable. However, this will cause a hard error if first is volatile-qualified (demo):

#include <iterator>

int main() {
  int arr[] = {1, 2, 3};
  int* volatile ptr = arr;
  // return std::distance(ptr, arr + 3);      // this is ok
  return std::ranges::distance(ptr, arr + 3); // hard error
}

The resolution changes the Effects of LWG 3664 from "cute" to "noncute".