Dramatic performance change by adding additional unused method

General Usage Performance
22

I tried with having a Vector of abstract types. Like this:

abstract type AbstractPlacement{T<:AbstractFloat} end

#---Volume-------------------------------------------------------------------------
struct Volume{T<:AbstractFloat, S<:AbstractShape{T}, M<:AbstractMaterial}
    label::String
    shape::S                            # Reference to the actual shape
    material::M                         # Reference to material
    daughters::Vector{AbstractPlacement{T}}
end

#---PlacedVolume-------------------------------------------------------------------
struct PlacedVolume{T<:AbstractFloat,S<:AbstractShape{T}, M<:AbstractMaterial} <: AbstractPlacement{T}
    transformation::Transformation3D{T}
    volume::Volume{T,S,M}
end

Volume{T}(label::String, shape::S, material::M) where {T,S,M} = Volume{T,S,M}(label, shape, material, Vector{AbstractPlacement{T}}())

The performance is twice worst than what I had originally.