Function gmp_mpfr_sys::mpfr::mpfr_custom_init_set

pub unsafe extern fn mpfr_custom_init_set(arg1: mpfr_ptr,
                                          arg2: c_int,
                                          arg3: mpfr_exp_t,
                                          arg4: mpfr_prec_t,
                                          arg5: *mut c_void)