This restricts the API of the CPOs and other function objects so they
cannot be misused by deriving from them or taking their addresses.
Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/ranges_base.h (ranges::begin, ranges::end)
(ranges::cbegin, ranges::cend, ranges::rbeing, ranges::rend)
(ranges::crbegin, ranges::crend, ranges::size, ranges::ssize)
(ranges::empty, ranges::data, ranges::cdata): Make types final.
Add deleted operator& overloads.
(ranges::advance, ranges::distance, ranges::next, ranges::prev):
Likewise.
* testsuite/std/ranges/headers/ranges/synopsis.cc: Replace
ill-formed & expressions with using-declarations. Add checks for
other function objects.
8b93548778