[Bug c++/46134] constexpr vs. defaulted ctor

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46134

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> 2010-11-02 12:33:17 UTC ---
(In reply to comment #5)
> constexpr
> unique_ptr() : _M_t(pointer(), __uninitialized_deleter()) { }

IIUC since that tuple constructor is not constexpr, that makes this unique_ptr
constructor not a constexpr constructor either.