[PATCH 3/3] libstdc++: Implement remaining piece of LWG 3448

[Jonathan Wakely]

On 26/08/20 16:44 -0400, Patrick Palka via Libstdc++ wrote:
>Almost all of the proposed resolution for LWG 3448 is already
>implemented; the only part left is to adjust the return type of
>transform_view::sentinel::operator-.
>
>libstdc++-v3/ChangeLog:
>
>	LWG 3448
>	PR libstdc++/95322
>	* include/std/ranges (transform_view::__distance_from): Give
>	this a deduced return type.
>	(transform_view::sentinel::operator-): Adjust the return type so
>	that it's based on the constness of the iterator rather than
>	that of the sentinel.
>	* testsuite/std/ranges/adaptors/95322.cc: Refer to LWG 3488.

Also OK, thanks for fixing these.