The implicit definition of a copy constructor
as defaulted
is deprecated if the class has a
user-declared copy assignment operator or a user-declared destructor
.The implicit
definition of a copy assignment operator
as defaulted is deprecated if the class has a user-declared
copy constructor or a user-declared destructor (
[class.dtor],
[class.copy])
.In a future revision of this International Standard, these implicit definitions
could become deleted (
[dcl.fct.def])
.