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

[glisse at gcc dot gnu.org]

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

Marc Glisse <glisse at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |glisse at gcc dot gnu.org

--- Comment #4 from Marc Glisse <glisse at gcc dot gnu.org> 2012-12-16 22:47:34 UTC ---
libc++'s implementation has the drawback that a tuple of empty types is not
empty (at least with the current ABI).

It seems a shame that sfinae now manages to handle access control cleverly
enough to disable overloads but regular code still handles access control as
something that is only checked after the fact.