diff --git a/libc3/types.h b/libc3/types.h
index 541d3d6..ad7efe3 100644
--- a/libc3/types.h
+++ b/libc3/types.h
@@ -26,6 +26,12 @@
#ifdef bool
# undef bool
#endif
+#ifdef false
+# undef false
+#endif
+#ifdef true
+# undef true
+#endif
/* Basic integer types. */
typedef char s8;