This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 110. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2022-11-27


1928. Triviality of deleted special member functions

Section: 11.4.5.3  [class.copy.ctor]     Status: NAD     Submitter: Richard Smith     Date: 2014-05-15

The current wording of the Standard does not make clear whether a special member function that is defaulted and implicitly deleted is trivial. Triviality is visible in various ways that don't involve invoking the function, such as determining whether a type is trivially copyable and determining the result of various type traits. It also factors into some ABI specifications.

(See also issue 1734.)

Notes from the June, 2014 meeting:

CWG felt that deleted functions should be trivial. See also issue 1590.

Additional note, November, 2014:

See paper N4148.

Additional note, October, 2015:

Moved from "extension" status to "open" to allow consideration by CWG. See the additional discussion in issue 1734 for further details. See also issue 1496.

Rationale (October, 2015):

CWG feels that the triviality of a deleted function should be irrelevant. Any cases in which the triviality of a deleted function is observable should be amended to remove that dependency.