Avoid deduplicating linkopts of cc_shared_library dependencies.

Linker inputs for dependencies of `cc_shared_library` are currently passing their `linkopts` as a `depset`, which leads to deduplication of the flags thereby passed. Consequently, a sequence of well-formed flags like `-framework Security -framework IOKit` gets collapsed to `-framework Security IOKit`; the linker then interprets `IOKit` as an object file that it's unable to locate, which yields a malformed link line.

Passing `linkopts` directly rather than wrapping it in `depset` appears to resolve the issue. I've added a test that replicates the original issue; since `-framework` isn't meaningful on all platforms, I've only enabled it for MacOS.

Note that the tests in this repository utilize the `rules_cc` repository rather than the built-in rules; therefore, I don't think the new test can be expected to pass until the change has been propagated there, and the controlling [`MODULE.bazel.lock` entry](https://github.com/bazelbuild/bazel/blob/HEAD/src/test/tools/bzlmod/MODULE.bazel.lock#L113) has been updated. I've tested it locally by `cat`ing a `local_path_override` directive to the `MODULE.bazel` file that [gets synthesized](https://github.com/bazelbuild/bazel/blob/e887cfbfd641f57a3cdd950249daf9b568ebaeb5/src/main/starlark/tests/builtins_bzl/cc_builtin_tests.sh#L49) for these tests, in order to point the tests towards a local fork of `rules_cc` with this same change applied; under these conditions, the test passes.

Closes #27735.

Closes #27755.

PiperOrigin-RevId: 845984933
Change-Id: I866456d29e851d24984b7d91f4613bc2df6ae2ad
1 file changed
tree: 2aed0748a3de821200d7eddb37272ad5ab3599b5
  1. .bazelci/
  2. .bcr/
  3. .github/
  4. cc/
  5. docs/
  6. examples/
  7. tests/
  8. .bazelignore
  9. .bazelrc
  10. .gitignore
  11. AUTHORS
  12. BUILD
  13. CODEOWNERS
  14. CONTRIBUTING.md
  15. googletest.patch
  16. ISSUE_TEMPLATE.md
  17. LICENSE
  18. MODULE.bazel
  19. README.md
  20. renovate.json
  21. WORKSPACE
  22. WORKSPACE.bzlmod
README.md

C++ rules for Bazel

  • Postsubmit Build status

This repository contains a Starlark implementation of C++ rules in Bazel.

The rules are being incrementally converted from their native implementations in the Bazel source tree.

For the list of C++ rules, see the Bazel documentation.

Getting Started

Add the following to your WORKSPACE file:

load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")

http_archive(
    name = "rules_cc",
    urls = ["https://github.com/bazelbuild/rules_cc/archive/refs/tags/<VERSION>.tar.gz"],
    sha256 = "...",
)

Then, in your BUILD files, import and use the rules:

load("@rules_cc//cc:defs.bzl", "cc_library")

cc_library(
    ...
)

Using the rules_cc toolchain

This repo contains an auto-detecting toolchain that expects to find tools installed on your host machine. This is non-hermetic, and may have varying behaviors depending on the versions of tools found.

There are third-party contributed hermetic toolchains you may want to investigate:

If you'd like to use the cc toolchain defined in this repo, add this to your WORKSPACE after you include rules_cc:

load("@rules_cc//cc:repositories.bzl", "rules_cc_dependencies", "rules_cc_toolchains")

rules_cc_dependencies()

rules_cc_toolchains()

Migration Tools

This repository also contains migration tools that can be used to migrate your project for Bazel incompatible changes.

Legacy fields migrator

Script that migrates legacy crosstool fields into features (incompatible flag, tracking issue).

TLDR:

bazel run @rules_cc//tools/migration:legacy_fields_migrator -- \
  --input=my_toolchain/CROSSTOOL \
  --inline

Contributing

Bazel and rules_cc are the work of many contributors. We appreciate your help!

To contribute, please read the contribution guidelines: CONTRIBUTING.md.

Note that the rules_cc use the GitHub issue tracker for bug reports and feature requests only. For asking questions see: