pub unsafe extern "C" fn arf_complex_mul_fallback(
e: *mut arf_struct,
f: *mut arf_struct,
a: *const arf_struct,
b: *const arf_struct,
c: *const arf_struct,
d: *const arf_struct,
prec: mp_limb_signed_t,
rnd: c_int,
) -> c_int