Important changes:

- Aspects can now define and use exec groups using the same API as

rules.

This release contains contributions from many people at Google, as well as Kaiqin Chen.

Incompatible changes:

- this incompatible change breaks old instances of http_archive

that specified netrc as an absolute path. It is unlikely there

are many instances in the wild since the path would refer to a

netrc file inside the external repository by absolute path.

Migration should be straightforward.

- genrule switched to use exec transition instead of host. This can

break targets with hardcoded output paths. To avoid using

hardcoded paths use make variables, see

https://docs.bazel.build/versions/4.2.2/be/make-variables.html#pre

defined_label_variables

- this incompatible change breaks old instances of http_archive

that specified netrc as an absolute path. It is unlikely there

are many instances in the wild since...

- Error Prone now checks for unused return values of additional

methods on `java.lang.Object`, which can be disabled using

`--javacopts=-Xep:ReturnValueIgnored:OFF`

- Error Prone now checks for unused return values of additional

methods on `java.lang.Object`, which can be disabled using

`--javacopts=-Xep:ReturnValueIgnored:OFF`

- The --incompatible_existing_rules_immutable_view flag has been

flipped to true. See

https://github.com/bazelbuild/bazel/issues/13907 for

migration notes.

- Split up the C++ archive from the C++ link action and set

`CppArchive` as mnemonic.

- workspace(managed_directories=) is not available anymore.

- --legacy_important_outputs now has a default of false.

- --legacy_important_outputs default reverted to true.

- objc_library now requires CcInfo in its deps. If this breaks

you, add empty CcInfo() to your rule.

Important changes:

- Deprecate --incompatible_applicable_licenses flag, in preparation

for removal in Bazel 6.x.

- Treat py_*.srcs_version="PY2" the same as "PY2ONLY".

- The Build Event Protocol now contains file digests and sizes

along with the file name and URI.

- Refactor system suspend event handling.

- alias() can now select() directly on constraint_value()

- Allow \a \b \f \v escape sequences in Starlark.

- Match remote and local xcode version by most granular version.

- Adds `--experimental_worker_multiplex_sandboxing` flag that

controls whether to sandbox multiplex workers that support it.

- provider() has a new parameter: init, a callback for performing

pre-processing and validation of field values. Iff this parameter

is set,

provider() returns a tuple of 2 elements: the usual provider

symbol (which,

when called, invokes init) and a raw constructor (which bypasses

init).

- Tests that fail to create or complete their

`TestAttemptContinuation` by

throwing an `ExecException` will report an `INCOMPLETE` status.

Previously, Bazel

would fail to report any status for the test attempt.

- Fixed an issue where Bazel could erroneously report a test passes

in coverage mode without actually running the test.

- Include more information about configurations in cquery proto

formatted output. This deprecates the configuration field of

AnalysisProtosV2.ConfiguredTarget, and adds a new field,

configuration_id, to

be used instead.

- experimental cc_library.implementation_deps inverted to

interface_deps

- In aquery and cquery proto output, indicate if a configuration is

a

tool or non-tool configuration.

- Include complete configurations in cquery proto output.

- experimental cc_library.implementation_deps inverted to

interface_deps

- Make protocOpts() publicly accessible.

- Add some documentation about how configuration information is

conveyed in cquery proto output.

- Introduces experimental static library linking API under

apple_common.link_multi_arch_static_library

- Further deprecation and removal of pkg_tar. Stop supporting

legacy use of 'files' attribute, where it could be a list of

labels instead of a map of paths to labels.

- Removed --incompatible_no_build_defs_pkg flag. It never fulfilled

its purpose because --all_incompatible_changes would never set

it. The last rule it gated (pkg_tar) is scheduled to be removed

in Bazel 6.x.

- Add coverage configuration fragment, used to expose

output_generator label.

- Bazel now no longer includes system headers on macOS in coverage

reports (#14969).

- android_sdk_repository read $ANDROID_SDK_ROOT in addition to

$ANDROID_HOME.

- The default dexer is now d8. dx can be optionally enabled using:

--define=android_dexmerger_tool=dx_dexmerger \

--define=android_incremental_dexing_tool=dx_dexbuilder \

--define=android_standalone_dexing_tool=dx_compat_dx \

--use_workers_with_dexbuilder

- Packaging support for deploy JAR embedded JDK files (hermetic

Java).

- Don't stamp cc_common.link actions for tool dependencies.

- Starlark test rules can use the new inherited_environment

parameter of testing.TestEnvironment to specify environment

variables

whose values should be inherited from the shell environment.

- Enable merging permissions during Android manifest merging with

the --merge_android_manifest_permissions flag.

- Allow specialization to work with constraint_values.

- Bazel uses the D8 jar from Maven instead of the SDK.

- Make ijar / java_import preserve classes with `@kotlin.Metadata`

annotations

- Switch cc_test implementation to Starlark. Note: cc_test will now

link statically when _targeting_ Windows regardless of host

platform (rather than always linking statically when Windows is

the _host_).

- Switch cc_test implementation to Starlark. Note: cc_test will now

link statically when _targeting_ Windows regardless of host

platform (rather than always linking statically when Windows is

the _host_).

- Add devtools/build/lib/worker:work_request_handlers to the remote

android tools release package. This will be transitively packaged

into all_android_tools.

- Bazel uses the D8 jar from Maven instead of the SDK.

- android_sdk_repository read $ANDROID_SDK_ROOT in addition to

$ANDROID_HOME.

- Advance android_tools_pkg version to 0.24.0.

- Switch cc_test implementation to Starlark. Note: cc_test will now

link statically when _targeting_ Windows regardless of host

platform (rather

than always linking statically when Windows is the _host_).

- Bazel uses the D8 jar from Maven instead of the SDK.

- "blaze config" now only reports info from the last build. To

compare configurations across multiple builds, redirect "blaze

config" output to a file and run your favorite diff tool.

- The --incompatible_override_toolchain_transition flag is now

always set, and will be removed in the future. Thus,

--noincompatible_override_toolchain_transition has no effect, and

the value of the incompatible_use_toolchain_transition parameter

in aspect() and rule() builtins is ignored.

- Switch cc_test implementation to Starlark. Note: cc_test will now

link statically when _targeting_ Windows regardless of host

platform (rather

than always linking statically when Windows is the _host_).

- Toolchain types may now be optional, in addition to mandatory.

See https://bazel.build/docs/toolchains#optional-toolchains for

further details.

- Add six to deps of has_services=1 py_proto_librarys.

- pkg_tar(symlinks) has been removed. Users needing that feature

should

migrate to @rules_pkg.

This release contains contributions from many people at Google, as well as Adam Wolf, Albert Lloveras, Alessandro Patti, Alex Eagle, Alex Scott, Alex Torok, Andreas Fuchs, Andreas Herrmann, Andrew Katson, Andrew Klotz, arunkumar9t2, Ast-x64, Benedek Thaler, Benjamin Lee, Benjamin Peterson, Ben Lee, Bohdan Vanieiev, Bradley Burns, Brandon Duffany, Brandon Jacklyn, Brentley Jones, Brentley Jones, Chad Miller, Chris Clearwater, Chris Fredrickson, Christopher Peterson Sauer, Christopher Sauer, ckiffel, Cristian Hancila, crydell-ericsson, Dan Fleming, Daniel Wagner-Hall, Danny Wolf, David Ostrovsky, Denys Kurylenko, Dimi Shahbaz, divanorama, dmaclach, Ed Schouten, Emil Kattainen, Fabian Meumertzheim, floriographygoth, Fredrik Medley, George Prekas, gkgoat1, gkorlam, Greg Estren, Greg, Grzegorz Lukasik, Halil Sener, Hannes Kufler, homuler, hvadehra, hvd, Jan, Jay Bazuzi, jheaff1, Jiawen Chen, Joel Williamson, John Laxson, John Millikin, juanchoviedo, Keith Smiley, Ken Micklas, Kevin Lin, lihu, Luc Bertrand, Marek uppa, Matt Clarkson, Matt Mackay, Michael P. Nitowski, Mikhail Balabin, Mostyn Bramley-Moore, Nick Korostelev, Nitesh Anandan, Niyas Sait, Noa Resare, Oscar Bonilla, Patrick Balestra, Paul Tarjan, Peter Mounce, Philipp Schrader, Pras Velagapudi, Rahul Butani, Rifqi Mulya Fahmi, Ryan Beasley, Ryan Schmidt, Sahin Yort, Saleem Abdulrasool, Simon Bjorklen, Son Luong Ngoc, Stiopa Koltsov, Sven Tiffe, Takeo Sawada, Tao Wang, Ted Kaplan, Tetsuo Kiso, Thi Doan, Thomas Chen, ThomasCJY, Thomas Zayouna, Timothe Peignier, Tom de Goede, Ulf Adams, Ulrik Falklof, Vasilios Pantazopoulos, Vladimir Tagakov, William Muir, Xavier Bonaventura, Xdng Yng, Yannic Bonenberger, Yannic, Yesudeep Mangalapilly, Yuval K, Zhongpeng Lin.