LinearAlgebra/addmul/mul!(::Matrix{Float64}, ::LinearAlgebra.SymTridiagonal{Int64, V} where V<:AbstractVector{Int64}, ::LinearAlgebra.UnitUpperTriangular{Int64, S} where S<:AbstractMatrix{Int64}, α, β)/α = 1.1335488638285314, β = 0.0/adjoint and transpose/fa = transpose, fb = identity @test returned_mat === Ccopy