Fails to descend into Type constructors about cthulhu.jl HOT 3 CLOSED

julia> Base._methods_by_ftype(Tuple{Array{Int}, typeof(undef), Int}, -1, typemax(UInt))
0-element Array{Any,1}

julia> code_typed(Array{Int}, (typeof(undef), Int))
1-element Array{Any,1}:
 CodeInfo(
1 ─ %1 = $(Expr(:foreigncall, :(:jl_alloc_array_1d), Array{Int64,1}, svec(Any, Int64), :(:ccall), 2, Array{Int64,1}, :(m), :(m)))::Array{Int64,1}
└──      return %1
) => Array{Int64,1}

Base._methods(Array{Int}, Tuple{typeof(undef), Int}, -1, typemax(UInt))
1-element Array{Any,1}:
 svec(Tuple{Type{Array{Int64,N} where N},UndefInitializer,Int64}, svec(Int64), (::Type{Array{T,N} where N})(::UndefInitializer, m::Int64) where T in Core at boot.jl:416)