[Bug c++/63217] template conversion operator returning const reference not used for conversion in some cases

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63217

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Other related ones:
http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#493
http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#322
http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#913