At the end of his comic in the 80s, Barry goes to live in the future with Iris(or is it the other wife?), the 30th century, where they have Twins. One of the twins has a Son called Bart Allen, who grows up to be Impulse, travels back in time to the 20th century, and then Kid Flash and then Flash... And that's who was on Smallville. "Impulse" not "Flash". Bart's mother actually had a fling with Captain Boomerang, which is how Bart wound up with a Super speedster Brother called captain Boomerang Jr who could not make up his mind if he was a hero or a villain.