[Bug libstdc++/92064] [DR 3171] operator/ not resolved for directory_entry and const char*

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92064

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2019-10-11
            Summary|operator/ not resolved for  |[DR 3171] operator/ not
                   |directory_entry and const   |resolved for
                   |char*                       |directory_entry and const
                   |                            |char*
     Ever confirmed|0                           |1

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I believe this is the correct behaviour.

https://wg21.link/lwg3065 changed operator/ to be a hidden friend, which means
it can only be found by ADL when at least one argument is a path.

in the expression `dir / "file"` neither argument has type path, so the
operator is not found by ADL. You would need to do:

    dir.path() / "file"

or:

    static_cast<const path&>(dir) / "file"

However, as https://wg21.link/lwg3171 points out, such changes to path can have
undesirable consequences for directory_entry. I will ask for LWG 3171 to also
consider operator/ and the comparison operators.