CWG Issue 2242 (original) (raw)

This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 117a. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2025-04-13

2242. ODR violation with constant initialization possibly omitted

Section: 6.3 [basic.def.odr]Status: C++23Submitter: Hubert TongDate: 2016-03-05

P2720R0 comment US 5-033

[Accepted as a DR at the November, 2022 meeting.]

Consider the following example:

// tu1.cpp extern const int a = 1; inline auto f() { static const int b = a; struct A { auto operator()() { return &b; } } a; return a; }

// tu2.cpp extern const int a; inline auto f() { static const int b = a; struct A { auto operator()() { return &b; } } a; return a; } int main() { return *decltype(f())()(); }

Here, b may or may not have constant initialization. This example should be an ODR violation.

(Split off from issue 2123.)

Proposed resolution (approved by CWG 2022-11-11):

Insert after 6.3 [basic.def.odr] bullet 14.7 as follows: