Avoiding unbreakable reference cycle with value types and closures?

Evolution Pitches
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Reference-type easily have reference cycle because we allow it to have multiple points of access(POA). For example,

let a = Class() // Class #1
let b = a // also Class #1

So we say that Class 1 has 2 POAs; a and b.

Semantically, value-type always have only one POA. For example,

let a = Value() // Value #1
let b = a // treated as Value #2

So Value 1 has only one POA, a. And Value 2 has only b. That’s why weak reference makes no sence for value type; it’ll turn nil The moment it is assigned.

The problem with closure is that it allows any variable to have multiple POAs regardless of value/reference semantic.

let a = Value() // Value #1
let c = {
   use(a) // also Value #1
}

Now Value #1 has 2 POAs one in the local context, and another inside the closure.
Despite both being called a, it should be treated as a different POA as it lies in different scopes, and so Value #1 will be inaccessible only when both scopes expire.

So I think the short-term way of addressing this would be to allow closure to weakly capture the value type.

let a = Value()
let c = { [weak a]
    use(a)
}

Though if we’re revamping the Memory model anyway, effort/pay-off may not be very attractive.