Use cast in fprintf for arg.
@@ -56,7 +56,7 @@ int main (void) {
start_execution_time = real_usec_time ();
#if defined(TEST_GEN_LOOP)
res = fun (arg);
- fprintf (stderr, "fun (%ld) -> %ld", arg, (long) res);
+ fprintf (stderr, "fun (%ld) -> %ld", (long) arg, (long) res);
#else
res = fun ();
fprintf (stderr, "sieve () -> %ld", (long) res);
