This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 113d. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2024-03-20


1811. Lookup of deallocation function in a virtual destructor definition

Section: 11.4.7  [class.dtor]     Status: CD4     Submitter: Richard Smith     Date: 2013-11-18

[Moved to DR at the November, 2014 meeting.]

According to 11.4.7 [class.dtor] paragraph 12,

At the point of definition of a virtual destructor (including an implicit definition (11.4.5.3 [class.copy.ctor])), the non-array deallocation function is looked up in the scope of the destructor's class (6.5.2 [class.member.lookup]), and, if no declaration is found, the function is looked up in the global scope. If the result of this lookup is ambiguous or inaccessible, or if the lookup selects a placement deallocation function or a function with a deleted definition (9.5 [dcl.fct.def]), the program is ill-formed. [Note: This assures that a deallocation function corresponding to the dynamic type of an object is available for the delete-expression (11.4.11 [class.free]). —end note]

This specification is not sufficiently clear regarding the nature of the lookup. Presumably the intent is that the processing be parallel to that described in 7.6.2.9 [expr.delete], but that should be made explicit.

Proposed resolution (February, 2014):

Change 11.4.7 [class.dtor] paragraph 12 as follows:

At the point of definition of a virtual destructor (including an implicit definition (11.4.5.3 [class.copy.ctor])), the non-array deallocation function is looked up in the scope of the destructor's class (6.5.2 [class.member.lookup]), and, if no declaration is found, the function is looked up in the global scope determined as if for the expression delete this appearing in a non-virtual destructor of the destructor's class (see 7.6.2.9 [expr.delete]). If the result of this lookup is ambiguous or inaccessible, lookup fails or if the lookup selects a placement deallocation function or a function with deallocation function has a deleted definition (9.5 [dcl.fct.def]), the program is ill-formed. [Note: This assures that a deallocation function corresponding to the dynamic type of an object is available for the delete-expression (11.4.11 [class.free]). —end note]