1.17.0 (February 15, 2022)

This release updates the minimum supported Rust version (MSRV) to 1.49,
the mio dependency to v0.8, and the (optional) parking_lot
dependency to v0.12. Additionally, it contains several bug fixes, as
well as internal refactoring and performance improvements.

Fixed

• time: prevent panicking in sleep with large durations (#4495)
• time: eliminate potential panics in Instant arithmetic on platforms
  where Instant::now is not monotonic (#4461)
• io: fix DuplexStream not participating in cooperative yielding
  (#4478)
• rt: fix potential double panic when dropping a JoinHandle (#4430)

Changed

• update minimum supported Rust version to 1.49 (#4457)
• update parking_lot dependency to v0.12.0 (#4459)
• update mio dependency to v0.8 (#4449)
• rt: remove an unnecessary lock in the blocking pool (#4436)
• rt: remove an unnecessary enum in the basic scheduler (#4462)
• time: use bit manipulation instead of modulo to improve performance
  (#4480)
• net: use std::future::Ready instead of our own Ready future
  (#4271)
• replace deprecated atomic::spin_loop_hint with hint::spin_loop
  (#4491)
• fix miri failures in intrusive linked lists (#4397)

Documented

• io: add an example for tokio::process::ChildStdin (#4479)

Unstable

The following changes only apply when building with --cfg tokio_unstable:

• task: fix missing location information in tracing spans generated by
  spawn_local (#4483)
• task: add JoinSet for managing sets of tasks (#4335)
• metrics: fix compilation error on MIPS (#4475)
• metrics: fix compilation error on arm32v7 (#4453)