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#include <pthread.h>
#define COUNT 10000
static volatile int count;
static void racy_count(pthread_barrier_t *bar)
{
int i;
pthread_barrier_wait(bar);
for (i = 0; i < COUNT; i++)
count++;
}
static void *thread_fn(void *arg)
{
racy_count(arg);
return NULL;
}
int main(void)
{
pthread_t id[2];
pthread_barrier_t bar;
pthread_barrier_init(&bar, NULL, 3);
pthread_create(&id[0], NULL, thread_fn, &bar);
pthread_create(&id[1], NULL, thread_fn, &bar);
racy_count(&bar);
pthread_join(id[0], NULL);
pthread_join(id[1], NULL);
return !(count > 0);
}
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