7.4.1

### PLEASE READ ###

Bazelisk only reads the first line of this file. Don't move this up.

When upgrading bazel, you must also upgrade toolchains.

1. Install rbe_configs_gen:

1.1: $ git clone https://github.com/bazelbuild/bazel-toolchains

1.2: $ cd bazel-toolchains

1.3: $ go install ./cmd/rbe_configs_gen/rbe_configs_gen.go

2. Run it for Linux:

```

export NEW_BAZEL_VERSION=$(head -n 1 .bazelversion | tail -n 1)

export PATH_TO_RECLIENT=$PWD

export DOCKER_IMAGE="$(grep -Eio 'LINUX_DOCKER_IMAGE = "[^"]*' configs/defs.bzl | sed 's/LINUX_DOCKER_IMAGE = "//')"

rbe_configs_gen \

--output_src_root=${PATH_TO_RECLIENT} \

--output_config_path=configs/linux \

--exec_os=linux \

--target_os=linux \

--toolchain_container=${DOCKER_IMAGE} \

--bazel_version=${NEW_BAZEL_VERSION} \

--generate_java_configs=false

bazelisk run //:gazelle

```

Then:

1. Edit the cc_library in //configs/linux/cc/BUILD.bazel to include

`tags=["manual"]` so it isn't caught by `...` expansion.

2. Add `Copyright 2023 Google LLC` header for //configs/linux/cc/tools/cpp/empty.cc.

3. Edit the toolchain->exec_compatible_with in //configs/linux/config/BUILD to include "@linux_android1404//:no_android_toolchain"

3. Edit configs/linux/config/BUILD to refer to the constant in configs/defs.bzl

instead of hardcoding the docker image version.

3. Run it for Windows in PowerShell as an administrator.

(You'll need a windows GCE VM with docker enabled, gWindows cloudtop does not support docker)

$ gcloud auth configure-docker us-central1-docker.pkg.dev

# You must use your email to login, as service account does not have the permission to docker pull images from kokoro-container-bakery

$ gcloud auth login --no-launch-browser

$ $DOCKER_IMAGE = (Select-String -Path configs/defs.bzl -Pattern 'WINDOWS_DOCKER_IMAGE = "([^"]*)"' -AllMatches | ForEach-Object {$_.Matches.Groups[1].Value})

$ $NEW_BAZEL_VERSION = (Get-Content -Path .bazelversion -TotalCount 1)

$ $PATH_TO_RECLIENT = $PWD

$ rbe_configs_gen.exe `

--output_src_root=$PATH_TO_RECLIENT `

--output_config_path=configs/windows `

--exec_os=windows `

--target_os=windows `

--toolchain_container=$DOCKER_IMAGE `

--cpp_toolchain_target=cc-compiler-x64_windows-clang-cl `

--bazel_version=$NEW_BAZEL_VERSION `

--generate_java_configs=false

$ bazelisk run //:gazelle

Then:

1. Edit the cc_toolchain_suite in //configs/windows/cc/BUILD.bazel to include

`tags=["manual"]` so it isn't caught by `...` expansion.

2. Edit //configs/windows/config/BUILD to include "@bazel_tools//tools/cpp:clang-cl" for both:

- "cc-toolchain"'s exec_compatible_with field;

- "cc-toolchain"'s target_compatible_with field;

- "platform"'s constraint_values field;

3. Edit //configs/windows/config/BUILD to refer to the constant in configs/defs.bzl

instead of hardcoding the docker image version.