[steveklabnik]

> I'm claiming that

This is different than the claims that were made when we made this decision. Specifically, the cost angle. You can absolutely do this, but we don't turn it on by default due to its expense. See https://danluu.com/integer-overflow/ for example. From that link:

> Summing up, integer overflow checks ought to cost a few percent on typical integer-heavy workloads

That few percent matters. And the extensive discussion (in both directions) on HN: https://news.ycombinator.com/item?id=8765714

It would be reasonable to turn it on, but that's not the decision we made.

> Exactly my point why curl has no reason to be reimplemented in Rust now.

Again, I never said curl should be ported to Rust.