diff --git a/include/lib/libc/stdbool.h b/include/lib/libc/stdbool.h
index e39aef7..b58334c 100644
--- a/include/lib/libc/stdbool.h
+++ b/include/lib/libc/stdbool.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -9,8 +9,8 @@
 
 #define bool	_Bool
 
-#define true	1
-#define false	0
+#define true	(0 < 1)
+#define false	(0 > 1)
 
 #define __bool_true_false_are_defined	1