[slavapestov]

> let a: Double = -(1 + 2) + -(3 + 4) + -(5)

> Still fails on a very recent version of Swift, Swift 6.1.2, if my test works.

FWIW, the situation with this expression (and others like it) has improved recently:

- 6.1 fails to type check in ~4 seconds

- 6.2 fails to type check in ~2 seconds (still bad obviously, but it's doing the same amount of work in less time)

- latest main successfully type checks in 7ms. That's still a bit too slow though, IMO. (edit: it's just first-time deserialization overhead; if you duplicate the expression multiple times, subsequent instances type check in <1ms).