P3125 R4 constexpr pointer tagging

[wg21bot]

P3125R0 Pointer tagging (Hana Dusíková)

[hanickadot]

SG1 meeting in Tokyo

D3125R0 minutes

Poll: tagged pointers are a valuable facility that we want to see in C++

SF	F	N	A	SA
9	3	2	0	0

Result: unanimous consent

Poll: the design of tagged pointers should make an effort to maximize the chances
of being able to use the high order bits

SF	F	N	A	SA
0	1	4	8	0

Result: consensus against

[wg21bot]

P3125R1 constexpr pointer tagging (Hana Dusíková)

[ogiroux]

SG1 meeting in Wroclaw

P3125R1 Minutes

We want tagged pointer in constexpr
SF F N A SA
3 6 4 0 0
Unanimous consent

We want tagged pointer schemas (multiple tagging strategies controlled by user,
incl. adopting tagging that pre-exists and incl. implementation-defined tagging)
SF F N A SA
0 2 4 4 2
No consensus

We want tagged pointer to model a pointer (so you don't need to untag to use as a
pointer or iterator)(this does not mean it implicitly converts to pointer)
SF F N A SA
0 3 5 4 0
No consensus