Question about broadcasting

[jling]

Threaded push! different for supposedly similar array initializations

julia> Y = fill(Int[],3); julia> push!(Y[1], 9) 1-element Vector{Int64}: 9 julia> Y 3-element Vector{Vector{Int64}}: [9] [9] [9] julia> X = [Int[] for i=1:3] julia> push!(X[1], 9) 1-element Vector{Int64}: 9 julia> X 3-element Vector{Vector{Int64}}: [9] [] []