In reply to wch:
I also found that if I do a type casting as below, it compiles fine.
Can you show from where the match_in_scbd is called and how? Looks like “scbd.pop_front()” is returning an object of parent class and T is of type extended class. So casting is solving the issue. Not sure how “scbd” is filled or “match_in_scbd” is invoked.