rules_cc/README.md

C++ rules for Bazel

• Postsubmit
• Postsubmit + Current Bazel Incompatible flags

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

There is no need to use rules from this repository just yet. If you want to use rules_cc anyway, 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:

• LLVM: https://github.com/bazel-contrib/toolchains_llvm
• GCC (Linux only): https://github.com/f0rmiga/gcc-toolchain
• zig cc: https://github.com/uber/hermetic_cc_toolchain

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:

• Stack Overflow
• rules_cc mailing list
• Slack channel #cc on slack.bazel.build