SharedArray does not support undef constructors

[dlfivefifty]

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  | | |_| | | | (_| |  |  Version 0.7.0-alpha.20 (2018-06-02 06:26 UTC)
 _/ |\__'_|_|_|\__'_|  |  Commit c8ce43ad17 (0 days old master)
|__/                   |  x86_64-apple-darwin17.5.0

julia> using SharedArrays

julia> A = SharedArray{Int,1}(undef,10)
ERROR: MethodError: no method matching SharedArray{Int64,1}(::UndefInitializer, ::Int64)
Closest candidates are:
  SharedArray{Int64,1}(::Any, ::Any, ::Any, ::Any, ::Any) where {T, N} at /Users/solver/Projects/julia7/usr/share/julia/stdlib/v0.7/SharedArrays/src/SharedArrays.jl:46
  SharedArray{Int64,1}(::Integer...; kwargs...) where {T, N} at /Users/solver/Projects/julia7/usr/share/julia/stdlib/v0.7/SharedArrays/src/SharedArrays.jl:163
  SharedArray{Int64,1}(::Any) where T<:AbstractArray at abstractarray.jl:22

julia> A = SharedArray{Int,1}(10)
10-element SharedArray{Int64,1}:
 0
 0
 0
 0
 0
 0
 0
 0
 0
 0

[timholy]

Not only that, we should eliminate the one that doesn't take an initializer.