Recently when I was reading the TupleTableSlot code, I noticed that the field "tts_tuple" mentioned in the comment has been removed in the higher version, but it still exists in the comment.
Good catch. This should be a minor oversight in 4da597ed, in which the TupleTableSlot implementation has been splitted into different slot types, and tts_tuple has been removed from TupleTableSlot struct.
Besides, at tuptable.h:71, I think TTS_SHOULDFREE should be TTS_FLAG_SHOULDFREE.