https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85723
Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2019-02-11 See Also| |https://gcc.gnu.org/bugzill | |a/show_bug.cgi?id=53036 Ever confirmed|0 |1 --- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- Confirmed. We also don't yet implement the earlier change to that wording, from https://wg21.link/cwg1363 struct A { A() = default; A(int i = 0) { } }; static_assert(!__is_trivial(A), ""); This fails because G++ considers the class trivial, even though default-initialization would fail as ambiguous.