Function _acb_poly_binomial_transform_convolution 

pub unsafe extern "C" fn _acb_poly_binomial_transform_convolution(
    b: acb_ptr,
    a: acb_srcptr,
    alen: mp_limb_signed_t,
    len: mp_limb_signed_t,
    prec: mp_limb_signed_t,
)