SYM_UNION
case SYM_UNION:
sym->type == SYM_UNION ||
[SYM_UNION] = {'u', "union"},
case SYM_UNION:
{ remove_node($1); (*$3)->tag = SYM_UNION; $$ = $3; }
{ record_compound($1, $3, $4, SYM_UNION); $$ = $4; }