http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50641
--- Comment #2 from Daniel Krügler <daniel.kruegler at googlemail dot com> 2011-10-07 05:36:02 UTC --- 1) The outcome of is_constructible is expected, because you cannot construct From from To, the actually wanted test would have been static_assert(std::is_constructible<To, From>::value, "not constructible"); and this is correctly accepted. 2) The outcome of is_convertible is expected, because this traits is just a trait to test for copy-initialization. Just add the line To t2 = create<From>(); to your test function and this will fail too: "error: use of deleted function 'To::To(const To&)" This is expected because the current language requires that a temporary of the target type To will be created which is than moved/copied into the final To object. Alas, this must fail, because To does not have any copy constructor not move constructor. This looks like not-a-bug to me.
