the corresponding iteration value will not be produced. If a map entry is
created during iteration, that entry may be produced during the iteration or
may be skipped. The choice may vary for each entry created and from one
iteration to the next.
If the map is <code>nil</code>, the number of iterations is 0.
</li>

<li>
For channels, the iteration values produced are the successive values sent on

  The `DeclarativeValidationTakeover` feature gate remains disabled by default.  While disabled, validation errors produced by hand written validation are always return to the caller.  To switch to declarative validation is primary source of errors for migrated fields, enable this feature gate. ([#130728](https://github.com/kubernetes/kubernetes/pull/130728), [@jpbet...

Due to a [tagging bug in our Release Engineering tooling](https://github.com/kubernetes/release/issues/1080) during `v1.18.0-alpha.3`, we needed to push a manual tag (`v1.18.0-alpha.4`).

**No binaries have been produced or will be provided for `v1.18.0-alpha.4`.**

The changelog for `v1.18.0-alpha.4` is included as part of the [changelog since v1.18.0-alpha.3][#changelog-since-v1180-alpha3] section.

# v1.18.0-alpha.3

* Transition service account controller clients to TokenRequest API ([#72179](https://github.com/kubernetes/kubernetes/pull/72179), [@WanLinghao](https://github.com/WanLinghao))
* kubeadm: reimplemented IPVS Proxy check that produced confusing warning message. ([#75036](https://github.com/kubernetes/kubernetes/pull/75036), [@bart0sh](https://github.com/bart0sh))

* kubeadm now produces error during preflight checks if swap is enabled. Users, who can setup kubelet to run in unsupported environment with enabled swap, will be able to skip that preflight check. ([#55399](https://github.com/kubernetes/kubernetes/pull/55399), [@kad](https://github.com/kad))

* Add /bin/tee symlink to bazel build for busybox, so that CI builds have /bin/tee ([#55417](https://github.com/kubernetes/kubernetes/pull/55417), [@justinsb](https://github.com/justinsb))
* Reduce log noise produced by prometheus-to-sd, by bumping it to version 0.2.2. ([#54635](https://github.com/kubernetes/kubernetes/pull/54635), [@loburm](https://github.com/loburm))

* allow windows mount path ([#51240](https://github.com/kubernetes/kubernetes/pull/51240), [@andyzhangx](https://github.com/andyzhangx))
* Reduce log noise produced by prometheus-to-sd, by bumping it to version 0.2.2. ([#54635](https://github.com/kubernetes/kubernetes/pull/54635), [@loburm](https://github.com/loburm))

## Changelog since v1.19.0

## What's New (Major Themes)

### Dockershim deprecation

Docker as an underlying runtime is being deprecated. Docker-produced images will continue to work in your cluster with all runtimes, as they always have.

* Flex drivers by default do not produce metrics. Flex plugins can enable metrics collection by setting  the capability 'supportsMetrics' to true. Make sure the file system can support fs stat to produce metrics in this case. ([#67508](https://github.com/kubernetes/kubernetes/pull/67508), [@brahmaroutu](https://github.com/brahmaroutu))

- Fixes a goroutine leak in kube-apiserver when a request times out. ([#83333](https://github.com/kubernetes/kubernetes/pull/83333), [@lavalamp](https://github.com/lavalamp))
- Fixes the bug in informer-gen that it produces incorrect code if a type has nonNamespaced tag set. ([#80458](https://github.com/kubernetes/kubernetes/pull/80458), [@tatsuhiro-t](https://github.com/tatsuhiro-t))