Proposed resolution:

Change the declaration in 24.5.1.2, p5 from

 istream_iterator<T,charT,traits,Distance>& operator++(int);
 

to

 istream_iterator<T,charT,traits,Distance> operator++(int);
 

(that is, remove the `&').

The synopsis of istream_iterator::operator++(int) in 24.5.1 shows it as returning the iterator by value. 24.5.1.2, p5 shows the same operator as returning the iterator by reference. That's incorrect given the Effects clause below (since a temporary is returned). The `&' is probably just a typo.