Proposed resolution:

This wording is relative to N5014.

1. In subclause [simd.loadstore] replace all occurrences of

   R(first, n)
   

   by

   R(first, static_cast<size_t>(n))
   

[ 2025-10-22; Reflector poll. ]

Set priority to 3 after reflector poll.

Question was raised if we should use size_t instead of iter_difference_t for consistency with span.

Currently, `simd::unchecked_load`/`partial_load`/`unchecked_store`/`partial_store` construct a `span` via `span(first, n)` when taking an iterator `first` and its difference type `n`.

However, the construction is ill-formed when the difference type is an integer-class type; we should perform an explicit casting here.