[Bug libstdc++/90165] std::variant constructs wrong alternative

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90165

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2019-04-19
           Assignee|unassigned at gcc dot gnu.org      |redi at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The variant(T&&) constructor is being selected by overload resolution, because
we talk to apply this constraint:

remove_­cvref_­t<T> is neither a specialization of in_­place_­type_­t nor a
specialization of in_­place_­index_­t,