Proposed resolution (September, 2010): Change 7.6.1.3 [expr.call] paragraph 7 as follows:
...Passing a potentially-evaluated argument of class type (
Clause 11 [class])
with having a
non-trivial copy constructor, a non-trivial move
constructor, or a non-trivial destructor, with no
corresponding parameter is conditionally-supported, with
implementation-defined semantics. If the argument...