diff --git a/contrib/intarray/_int_selfuncs.c b/contrib/intarray/_int_selfuncs.c
index 01d6fe14a70..17dc6768ea5 100644
--- a/contrib/intarray/_int_selfuncs.c
+++ b/contrib/intarray/_int_selfuncs.c
@@ -178,7 +178,7 @@ _int_matchsel(PG_FUNCTION_ARGS)
 	if (query->size == 0)
 	{
 		ReleaseVariableStats(vardata);
-		return (Selectivity) 0.0;
+		PG_RETURN_FLOAT8(0.0);
 	}
 
 	/*