diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index 9e51b58dde0846e6b98e9b3569b7002b43641e0d..ca7a6e73c258c04867e962f42291a269ad527f44 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -93,12 +93,10 @@ typedef struct
 #define SECS_PER_MINUTE 60
 #define MINS_PER_HOUR	60
 
-#ifdef HAVE_INT64_TIMESTAMP
 #define USECS_PER_DAY	INT64CONST(86400000000)
 #define USECS_PER_HOUR	INT64CONST(3600000000)
 #define USECS_PER_MINUTE INT64CONST(60000000)
 #define USECS_PER_SEC	INT64CONST(1000000)
-#endif
 
 /*
  * Macros for fmgr-callable functions.