diff --git a/src/utils.jl b/src/utils.jl
index 3e1453f..1ea5fef 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -30,7 +30,7 @@ function _adddiag!(a::Union{Matrix, SparseMatrixCSC}, v::Real)
     return a
 end
 
-function _adddiag!(a::Union{Matrix, SparseMatrixCSC}, v::Vector, c::Real)
+function _adddiag!(a::Union{Matrix, SparseMatrixCSC}, v::AbstractVector, c::Real)
     @check_argdims eachindex(v) == axes(a, 1) == axes(a, 2)
     if c == one(c)
         for i in eachindex(v)
@@ -46,7 +46,7 @@ end
 
 _adddiag(a::Union{Matrix, SparseMatrixCSC}, v::Real) = _adddiag!(copy(a), v)
 _adddiag(a::Union{Matrix, SparseMatrixCSC}, v::Vector, c::Real) = _adddiag!(copy(a), v, c)
-_adddiag(a::Union{Matrix, SparseMatrixCSC}, v::Vector{T}) where {T<:Real} = _adddiag!(copy(a), v, one(T))
+_adddiag(a::Union{Matrix, SparseMatrixCSC}, v::AbstractVector{T}) where {T<:Real} = _adddiag!(copy(a), v, one(T))
 
 
 function wsumsq(w::AbstractVector, a::AbstractVector)