diff --git a/libcxx/include/__type_traits/is_unsigned.h b/libcxx/include/__type_traits/is_unsigned.h
--- a/libcxx/include/__type_traits/is_unsigned.h
+++ b/libcxx/include/__type_traits/is_unsigned.h
@@ -11,6 +11,8 @@
 
 #include <__config>
 #include <__type_traits/integral_constant.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_integral.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header