pub unsafe extern "C" fn secp256k1_ecdsa_sign_recoverable(
    cx: *const Context,
    sig: *mut RecoverableSignature,
    msg32: *const c_uchar,
    sk: *const c_uchar,
    noncefn: NonceFn,
    noncedata: *const c_void
) -> c_int
Available on crate feature recovery only.