diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c
index dcc2ad8d954..87d22a1e19e 100644
--- a/src/backend/utils/activity/pgstat.c
+++ b/src/backend/utils/activity/pgstat.c
@@ -822,6 +822,9 @@ pgstat_fetch_entry(PgStat_Kind kind, Oid dboid, Oid objoid)
 
 	pgstat_prep_snapshot();
 
+	/* clear padding */
+	memset(&key, 0, sizeof(struct PgStat_HashKey));
+
 	key.kind = kind;
 	key.dboid = dboid;
 	key.objoid = objoid;
diff --git a/src/backend/utils/activity/pgstat_shmem.c b/src/backend/utils/activity/pgstat_shmem.c
index 634b9678206..d743de951ab 100644
--- a/src/backend/utils/activity/pgstat_shmem.c
+++ b/src/backend/utils/activity/pgstat_shmem.c
@@ -406,11 +406,18 @@ PgStat_EntryRef *
 pgstat_get_entry_ref(PgStat_Kind kind, Oid dboid, Oid objoid, bool create,
 					 bool *created_entry)
 {
-	PgStat_HashKey key = {.kind = kind,.dboid = dboid,.objoid = objoid};
+	PgStat_HashKey key;
 	PgStatShared_HashEntry *shhashent;
 	PgStatShared_Common *shheader = NULL;
 	PgStat_EntryRef *entry_ref;
 
+	/* clear padding */
+	memset(&key, 0, sizeof(struct PgStat_HashKey));
+
+	key.kind = kind;
+	key.dboid = dboid;
+	key.objoid = objoid;
+
 	/*
 	 * passing in created_entry only makes sense if we possibly could create
 	 * entry.
@@ -881,10 +888,17 @@ pgstat_drop_database_and_contents(Oid dboid)
 bool
 pgstat_drop_entry(PgStat_Kind kind, Oid dboid, Oid objoid)
 {
-	PgStat_HashKey key = {.kind = kind,.dboid = dboid,.objoid = objoid};
+	PgStat_HashKey key;
 	PgStatShared_HashEntry *shent;
 	bool		freed = true;
 
+	/* clear padding */
+	memset(&key, 0, sizeof(struct PgStat_HashKey));
+
+	key.kind = kind;
+	key.dboid = dboid;
+	key.objoid = objoid;
+
 	/* delete local reference */
 	if (pgStatEntryRefHash)
 	{