--- /dev/null
+#include <stdlib.h>
+#include <stdio.h>
+#include <threads.h>
+#include <atomic>
+
+static int N = 2;
+
+std::atomic_int *x;
+
+static void a(void *obj)
+{
+ int idx = *((int *)obj);
+
+ if (idx > 0)
+ x[idx - 1].load(std::memory_order_relaxed);
+
+ if (idx < N)
+ x[idx].store(1, std::memory_order_relaxed);
+ else
+ x[0].load(std::memory_order_relaxed);
+}
+
+int user_main(int argc, char **argv)
+{
+ thrd_t *threads;
+ int *indexes;
+
+ if (argc > 1)
+ N = atoi(argv[1]);
+ if (N < 2) {
+ printf("Error: must have N >= 2\n");
+ return 1;
+ }
+ printf("N: %d\n", N);
+
+ threads = (thrd_t *)malloc((N + 1) * sizeof(thrd_t));
+ x = (std::atomic_int *)malloc(N * sizeof(std::atomic_int));
+ indexes = (int *)malloc((N + 1) * sizeof(int));
+
+ for (int i = 0; i < N + 1; i++)
+ indexes[i] = i;
+
+ for (int i = 0; i < N; i++)
+ atomic_init(&x[i], 0);
+
+ for (int i = 0; i < N + 1; i++)
+ thrd_create(&threads[i], (thrd_start_t)&a, (void *)&indexes[i]);
+
+ for (int i = 0; i < N + 1; i++)
+ thrd_join(threads[i]);
+
+ return 0;
+}