Index: libcfa/src/concurrency/locks.hfa
===================================================================
--- libcfa/src/concurrency/locks.hfa	(revision c5bbb9b954e58b4aeb28451ae617740c890cb1d3)
+++ libcfa/src/concurrency/locks.hfa	(revision f4e3532605af952cfe1cb3326fdb58115967582b)
@@ -1,2 +1,4 @@
+#pragma once
+
 #include <stdbool.h>