Add missing exit(0)

bench/bench-stl.cpp

@@ -234,4 +234,5 @@ int main(int argc, const char *argv[])
     test_function("DictS(m)  time", 1000000, test_dict_str2);
   if (n == 50)
     test_function("Sort   time", 10000000, test_sort);
+  exit(0);
 }