US 8-036 6.6p3.2 [basic.link] Internal linkage for const variables

[wg21bot]

The pre-C++17 hack of giving const-qualified variable declarations internal linkage is needless and harmful in a module unit.

Proposed change:

Give them module linkage, at least in the purview of a primary module interface unit if not in all module unit purviews.

[erichkeane]

EWG discussed this during the February 7th, 2023 morning session in Issaquah. The following poll was taken:

Forward D2788R0 to CWG as a resolution for US8-036 applied to C++23 and as a DR to C++20.	SF	F	N	A	SA
18	10	1	0	0

Result: Consensus

[jensmaurer]

CWG 2023-02-08: Reviewed D2788; needs updates.

[jensmaurer]

CWG 2023-02-09: Approved D2788R0.

[jensmaurer]

Accepted with modifications.