musl - musl - an implementation of the standard library for Linux-based systems

diff --git a/src/thread/pthread_cond_broadcast.c b/src/thread/pthread_cond_broadcast.c
index 4fab9994..7e5ea91c 100644
--- a/src/thread/pthread_cond_broadcast.c
+++ b/src/thread/pthread_cond_broadcast.c

@@ -30,8 +30,12 @@ int pthread_cond_broadcast(pthread_cond_t *c)

}

/* Move waiter count to the mutex */

- w = a_swap(&c->_c_waiters, 0);

- a_fetch_add(&m->_m_waiters, w);

+ for (;;) {

+ w = c->_c_waiters;

+ a_fetch_add(&m->_m_waiters, w);

+ if (a_cas(&c->_c_waiters, w, 0) == w) break;

+ a_fetch_add(&m->_m_waiters, -w);

+ }

/* Perform the futex requeue, waking one waiter unless we know

* that the calling thread holds the mutex. */