diff --git a/libcxx/include/compare b/libcxx/include/compare
--- a/libcxx/include/compare
+++ b/libcxx/include/compare
@@ -145,6 +145,7 @@
 #include <__compare/three_way_comparable.h>
 #include <__compare/weak_order.h>
 #include <__config>
+#include <version>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header