diff --git a/src/time_bucket.c b/src/time_bucket.c
index e7140ab05d7..60009f22383 100644
--- a/src/time_bucket.c
+++ b/src/time_bucket.c
@@ -49,7 +49,7 @@
 		(result) += (offset);                                                                      \
 	} while (0)
 
-const struct NullableDatum TS_NULL_DATUM = { .value = 0, .isnull = true };
+NullableDatum TS_NULL_DATUM = { .value = 0, .isnull = true };
 
 TS_FUNCTION_INFO_V1(ts_int16_bucket);
 TSDLLEXPORT Datum
diff --git a/src/time_bucket.h b/src/time_bucket.h
index 913c5b6eafd..4244ddbf1f7 100644
--- a/src/time_bucket.h
+++ b/src/time_bucket.h
@@ -10,7 +10,7 @@
 
 #include "export.h"
 
-extern TSDLLEXPORT const struct NullableDatum TS_NULL_DATUM;
+extern struct NullableDatum TS_NULL_DATUM;
 
 extern TSDLLEXPORT Datum ts_int16_bucket(PG_FUNCTION_ARGS);
 extern TSDLLEXPORT Datum ts_int32_bucket(PG_FUNCTION_ARGS);