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This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 119a. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2025-12-20

1201. Are deleted and defaulted functions definitions?

[Voted into the WP at the March, 2011 meeting.]

According to 6.3 [basic.def.odr] paragraph 2,

A declaration is adefinition unless it declares a functionwithout specifying the function's body (9.6 [dcl.fct.def]), itcontains theextern specifier (9.2.2 [dcl.stc]) or alinkage-specification²⁵ (9.12 [dcl.link])and neither aninitializer nor afunction-body...

Because= delete and= default are not formsoffunction-body, this description does not cover defaultedand deleted functions, even though these declarations are elsewherereferred to as being definitions.

Proposed resolution (January, 2011):

Change the grammar in 9.6.1 [dcl.fct.def.general] paragraph 1as follows:

function-definition:
attribute-specifier-seq_opt decl-specifier-seqopt declarator function-body
attribute-specifier-seq_opt decl-specifier-seqopt declarator= default ;
attribute-specifier-seq_opt decl-specifier-seqopt declarator= delete ;

function-body:
ctor-initializer_opt compound-statement
function-try-block
= default ;
= delete ;