This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 108i. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2022-07-16


2509. decl-specifier-seq in lambda-specifiers

Section: 7.5.5.1  [expr.prim.lambda.general]     Status: DR     Submitter: Jens Maurer     Date: 2021-10-28

[Accepted at the February, 2022 meeting.]

(From editorial issue 2338.)

Use of decl-specifier-seq in the production for lambda-specifiers is too general and should be restricted.

Proposed resolution (December, 2021):

  1. Change the grammar in 7.5.5.1 [expr.prim.lambda.general] as follows:

  2. Change 7.5.5.1 [expr.prim.lambda.general] paragrap 3 as follows:

  3. In the decl-specifier-seq of the lambda-declarator, each decl-specifier shall be one of mutable, constexpr, or consteval. A lambda-specifier-seq shall contain at most one of each lambda-specifier and shall not contain both constexpr and consteval. If the lambda-declarator contains an explicit object parameter (9.3.4.6 [dcl.fct]), then no decllambda-specifier in the decllambda-specifier-seq shall be mutable.