diff --git a/libgcc/ChangeLog b/libgcc/ChangeLog
index 44fe7327ca4..1be4f87fe65 100644
--- a/libgcc/ChangeLog
+++ b/libgcc/ChangeLog
@@ -1,3 +1,7 @@
+2018-10-30  Rasmus Villemoes  <rv@rasmusvillemoes.dk>
+
+	* config/gthr-vxworks.h (__gthread_mutex_destroy): Call semDelete.
+
 2018-10-25  Martin Liska  <mliska@suse.cz>
 
 	PR other/87735
diff --git a/libgcc/config/gthr-vxworks.h b/libgcc/config/gthr-vxworks.h
index e43253b01c7..e974aa79368 100644
--- a/libgcc/config/gthr-vxworks.h
+++ b/libgcc/config/gthr-vxworks.h
@@ -63,8 +63,9 @@ __gthread_mutex_init_function (__gthread_mutex_t *mutex)
 }
 
 static inline int
-__gthread_mutex_destroy (__gthread_mutex_t * UNUSED(mutex))
+__gthread_mutex_destroy (__gthread_mutex_t *mutex)
 {
+  semDelete(*mutex);
   return 0;
 }