Comment 7 for bug 622406

You are one of the very few people who knows it by heart. I know more
than 99% of people and I did not know that N_COLS means "table flags."
 People who use this will think that Percona makes stupid mistakes
when writing code that subtracts numbers; it will be an embarrassment
to us. We either need to document this feature, or rename it. I
would strongly prefer to rename it, and then the documentation can say
"internally this has a different name, but we renamed it so it would
be more obvious what it means." I think we have to put users first,
not InnoDB developers.