Self-initialization of a static constexpr variable, is it well-formed?

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This was clarified and made ill-formed by defect report 2026: Zero-initialization and constexpr which asks:

According to 3.6.2 [basic.start.init] paragraph 2,

Variables with static storage duration (3.7.1 [basic.stc.static]) or
thread storage duration (3.7.2 [basic.stc.thread]) shall be
zero-initialized (8.5 [dcl.init]) before any other initialization
takes place.

Does this apply to constant initialization as well? For example,
should the following be well-formed, relying on the presumed
zero-initialization preceding the constant initialization?

constexpr int i = i;
struct s {
  constexpr s() : v(v) { }
  int v;
};
constexpr s s1;

The note before the proposed resolution says:

CWG agreed that constant initialization should be considered as happening instead of zero initialization in these cases, making the declarations ill-formed.

and the proposed resolution clarifies and amongst many changes, removes the following wording:

Variables with static storage duration (3.7.1) or thread storage duration (3.7.2) shall be zero-initialized (8.5)
before any other initialization takes place. […]

and adds the following wording:

If constant initialization is not performed, a variable with static storage duration (3.7.1 [basic.stc.static]) or thread storage duration (3.7.2 [basic.stc.thread]) is zero-initialized (8.5 [dcl.init]). […]

It is a large change, it renames [basic.start.init] to [basic.start.static] and created a new section [basic.start.dynamic] and modifies [stmt.dcl]

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