--- /dev/null
+#include <stdlib.h>
+#include <stdio.h>
+#include <threads.h>
+#include <stdatomic.h>
+
+#include "librace.h"
+#include "model-assert.h"
+
+atomic_int x;
+atomic_int y;
+atomic_int z;
+static void a(void *obj)
+{
+ atomic_load_explicit(&z, memory_order_relaxed); // this is only for schedule control
+ int t1=atomic_load_explicit(&x, memory_order_relaxed);
+ atomic_store_explicit(&y, 1, memory_order_relaxed);
+ printf("t1=%d\n",t1);
+}
+
+static void b(void *obj)
+{
+ int t2=atomic_load_explicit(&y, memory_order_relaxed);
+ atomic_store_explicit(&x, t2, memory_order_relaxed);
+}
+
+int user_main(int argc, char **argv)
+{
+ thrd_t t1, t2;
+
+
+ atomic_init(&x, 0);
+ atomic_init(&y, 0);
+ atomic_init(&z, 0);
+ thrd_create(&t1, (thrd_start_t)&a, NULL);
+ thrd_create(&t2, (thrd_start_t)&b, NULL);
+
+ thrd_join(t1);
+ thrd_join(t2);
+
+
+ return 0;
+}