[Bug libstdc++/55713] std::tuple incorrectly is convertible to "ElementType" when it is an empty class

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55713



--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-12-16 
17:49:20 UTC ---

This was done for an optimization. And I think it is allowed by the C++

standard too.