diff --git a/src/ChangeLog b/src/ChangeLog
index a11562b4d7a..ec43b7b2f72 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -2,6 +2,7 @@
 
 	* sysdep.c (_FILE_OFFSET_BITS): Make this hack even uglier
 	by pacifying GCC about it.  Maybe it's time to retire it?
+	* xfaces.c (USG, __TIMEVAL__): Likewise.
 
 	* dispextern.h (struct redisplay_interface): Rename param
 	to avoid shadowing.
diff --git a/src/xfaces.c b/src/xfaces.c
index 5cfe99d1285..fbed183522a 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -273,6 +273,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <X11/Xos.h>
 #define USG
 #define __TIMEVAL__
+#if defined USG || defined __TIMEVAL__ /* Don't warn about unused macros.  */
+#endif
 #else /* not XOS_NEEDS_TIME_H */
 #include <X11/Xos.h>
 #endif /* not XOS_NEEDS_TIME_H */