https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67557
--- Comment #3 from Georg Baum <Georg.Baum at post dot rwth-aachen.de> --- Can you please explain why ยง12.6.2 - 14 is applicable? I do not see any member function (virtual or not) being called on the partially constructed object. I still think that this is valid code with well defined behaviour.