Function antic::fmpz_mat_window_init

pub unsafe extern "C" fn fmpz_mat_window_init(
    window: *mut fmpz_mat_struct, 
    mat: *mut fmpz_mat_struct, 
    r1: mp_limb_signed_t, 
    c1: mp_limb_signed_t, 
    r2: mp_limb_signed_t, 
    c2: mp_limb_signed_t
)