Fix accidental refactor with different patterns.

src/KLU.jl

@@ -560,6 +560,7 @@ end
 
 function klu!(K::KLUFactorization{U}, S::SparseMatrixCSC{U}) where {U}
     size(K) == size(S) || throw(ArgumentError("Sizes of K and S must match."))
+    K.colptr == S.colptr && K.rowval == S.rowval || throw(ArgumentError("The pattern of the original matrix must match the pattern of the refactor."))
     return klu!(K, S.nzval)
 end
 #B is the modified argument here. To match with the math it should be (klu, B). But convention is