ScopedValue is allocating when accessed about julia HOT 4 OPEN

I guess not. Apparently we do not have calling convention support for Union{Struct, Ghost}, even though we very easily could (we have many variations on it already) and probably should (it is the iteration protocol)

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This is probably caused by 5b2fcb6 and is not multi-threading related:

julia> const dynvec = ScopedValue([0])
julia> @noinline function dynfun()
           dvec = dynvec[]
           dvec[1] += 1
           return nothing
       end
julia> foo() = @with dynvec=>[0] for _ in 1:1000_000; dynfun(); end

julia> @allocated foo()
16000208

The problem is this @noinline which forces a wrapping Tuple{Vector{Int}} to be allocated as a temporary, even though it is immediately unwrapped at every call-site:

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So is the problem there that the API wrongly returns an object of type (leaf.val,) instead of Some{V}(leaf.val)?

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Would Some{V}(leaf.val) bypass the need to allocate the temporary here?

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