4 files changed, 18 insertions, 11 deletions
diff --git a/src/internal/pthread_impl.h b/src/internal/pthread_impl.h
index 826191c2..848ff668 100644
--- a/src/internal/pthread_impl.h
+++ b/src/internal/pthread_impl.h
@@ -33,9 +33,9 @@ struct pthread {
 	pthread_attr_t attr;
 	volatile int dead;
 	struct {
-		void **head;
+		volatile void *volatile head;
 		long off;
-		void *pending;
+		volatile void *volatile pending;
 	} robust_list;
 	int unblock_cancel;
 	int timer_id;
diff --git a/src/thread/pthread_mutex_trylock.c b/src/thread/pthread_mutex_trylock.c
index 8d256614..31587e1f 100644
--- a/src/thread/pthread_mutex_trylock.c
+++ b/src/thread/pthread_mutex_trylock.c
@@ -9,6 +9,7 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m)
 
 	if (!self->robust_list.off) {
 		__syscall(SYS_set_robust_list, &self->robust_list, 3*sizeof(long));
+		self->robust_list.head = &self->robust_list.head;
 		self->robust_list.off = (char*)&m->_m_lock-(char *)&m->_m_next;
 	}
 
@@ -29,10 +30,11 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m)
 		return EBUSY;
 	}
 
-	m->_m_next = self->robust_list.head;
+	volatile void *next = self->robust_list.head;
+	m->_m_next = next;
 	m->_m_prev = &self->robust_list.head;
-	if (self->robust_list.head)
-		self->robust_list.head[-1] = &m->_m_next;
+	if (next != &self->robust_list.head) *(volatile void *volatile *)
+		((char *)next - sizeof(void *)) = &m->_m_next;
 	self->robust_list.head = &m->_m_next;
 	self->robust_list.pending = 0;
 
diff --git a/src/thread/pthread_mutex_unlock.c b/src/thread/pthread_mutex_unlock.c
index 42837516..46761d9a 100644
--- a/src/thread/pthread_mutex_unlock.c
+++ b/src/thread/pthread_mutex_unlock.c
@@ -21,8 +21,11 @@ int pthread_mutex_unlock(pthread_mutex_t *m)
 			self->robust_list.pending = &m->_m_next;
 			__vm_lock_impl(+1);
 		}
-		*(void **)m->_m_prev = m->_m_next;
-		if (m->_m_next) ((void **)m->_m_next)[-1] = m->_m_prev;
+		volatile void *prev = m->_m_prev;
+		volatile void *next = m->_m_next;
+		*(volatile void *volatile *)prev = next;
+		if (next != &self->robust_list.head) *(volatile void *volatile *)
+			((char *)next - sizeof(void *)) = prev;
 	}
 	cont = a_swap(&m->_m_lock, (type & 8) ? 0x40000000 : 0);
 	if (type != PTHREAD_MUTEX_NORMAL && !priv) {
diff --git a/src/thread/pthread_mutexattr_setrobust.c b/src/thread/pthread_mutexattr_setrobust.c
index 8948cbaf..d0627889 100644
--- a/src/thread/pthread_mutexattr_setrobust.c
+++ b/src/thread/pthread_mutexattr_setrobust.c
@@ -4,16 +4,18 @@
 void __do_private_robust_list()
 {
 	pthread_t self = __pthread_self();
-	void **p, **prev, **next;
+	volatile void *volatile *p;
+	volatile void *volatile *prev;
+	volatile void *volatile *next;
 	pthread_mutex_t *m;
 
-	for (prev=0, p=self->robust_list.head; p; p=next) {
+	prev = &self->robust_list.head;
+	for (p=self->robust_list.head; p&&p!=&self->robust_list.head; p=next) {
 		next = *p;
 		m = (void *)((char *)p - offsetof(pthread_mutex_t, _m_next));
 		if (!(m->_m_type & 128)) {
 			int waiters = m->_m_waiters;
-			if (prev) *prev = next;
-			else self->robust_list.head = next;
+			*prev = next;
 			int cont = a_swap(&m->_m_lock, self->tid|0x40000000);
 			if (cont < 0 || waiters) __wake(&m->_m_lock, 1, 1);
 		} else {