diff --git a/Python/thread_pthread.h b/Python/thread_pthread.h
--- a/Python/thread_pthread.h
+++ b/Python/thread_pthread.h
@@ -310,6 +310,7 @@
 
     status = sem_destroy(thelock);
     CHECK_STATUS("sem_destroy");
+    if(error) {} /* Avoid warnings. See issue #16588 */
 
     free((void *)thelock);
 }
@@ -366,6 +367,8 @@
         }
     }
 
+    if(error) {} /* Avoid warnings. See issue #16588 */
+
     if (status == 0) {
         success = PY_LOCK_ACQUIRED;
     } else if (intr_flag && status == EINTR) {
@@ -389,6 +392,7 @@
 
     status = sem_post(thelock);
     CHECK_STATUS("sem_post");
+    if(error) {} /* Avoid warnings. See issue #16588 */
 }
 
 #else /* USE_SEMAPHORES */