pub unsafe extern "C" fn tsk_treeseq_trait_linear_model(
    self_: *const tsk_treeseq_t,
    num_weights: tsk_size_t,
    weights: *const f64,
    num_covariates: tsk_size_t,
    covariates: *const f64,
    num_windows: tsk_size_t,
    windows: *const f64,
    options: tsk_flags_t,
    result: *mut f64
) -> c_int