Table alias cannot be used in GROUPING SETS clause if there are more than one column in it

EXPLAIN 
SELECT alias.a, alias.b, alias.c, COUNT(DISTINCT d) 
FROM table_name alias 
GROUP BY alias.a, alias.b, alias.c 
GROUPING SETS( (alias.a), (alias.b, alias.a) ); 
FAILED: ParseException line 15:34 missing ) at ',' near '<EOF>' 
line 16:0 extraneous input ')' expecting EOF near '<EOF>' 

EXPLAIN 
SELECT a, b, c, COUNT(DISTINCT d) 
FROM table_name 
GROUP BY a, b, c 
GROUPING SETS( (a), (b, a) ); 

EXPLAIN 
SELECT alias.a, alias.b, alias.c, COUNT(DISTINCT d) 
FROM table_name alias 
GROUP BY alias.a, alias.b, alias.c 
GROUPING SETS( (alias.a) );