LinearAlgebra/addmul/mul!(::LinearAlgebra.LowerTriangular{Float64, S} where S<:AbstractMatrix{Float64}, ::LinearAlgebra.UnitLowerTriangular{Float64, S} where S<:AbstractMatrix{Float64}, ::LinearAlgebra.Diagonal{Float64, V} where V<:AbstractVector{Float64}, α, β)/α = 1.0, β = -1.1675539845280296/β = 0 ignores C .= NaN @test returned_mat === Ccopy