Function igraph_sparsemat_lusol 

pub unsafe extern "C" fn igraph_sparsemat_lusol(
    A: *const igraph_sparsemat_t,
    b: *const igraph_vector_t,
    res: *mut igraph_vector_t,
    order: igraph_int_t,
    tol: igraph_real_t,
) -> igraph_error_t