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bazel / crubit / 1e26ccba0f2a05967df5d1b003e478deb25485d3
commit1e26ccba0f2a05967df5d1b003e478deb25485d3[log] [tgz]
authorGoogler <no-reply@google.com>Mon Jun 17 06:20:07 2024 -0700
committerCopybara-Service <copybara-worker@google.com>Mon Jun 17 06:21:15 2024 -0700
tree24d2cdffb506ba682b4a953c394400202b96e688
parent46534e8180c8e7dd9eda09aa4b91b017b8d7e6f6 [diff]
Expose API for getting edit ranges that are not inference targets.

This can be used for adding/removing explicit annotations when adding a default nullability setting, for ranges that are not (yet) targeted by inference tooling.

Renames existing API to clarify the distinction.

No test included, because it would be sensitive only to action at a distance when the definition of inference targets change.

PiperOrigin-RevId: 643984048
Change-Id: I8f78241b239a4dc0e216ebac5a573a7df4bdd356
2 files changed
tree: 24d2cdffb506ba682b4a953c394400202b96e688
  1. .bazelci/
  2. bazel/
  3. cc_bindings_from_rs/
  4. common/
  5. docs/
  6. examples/
  7. features/
  8. lifetime_analysis/
  9. lifetime_annotations/
  10. migrator/
  11. nullability/
  12. rs_bindings_from_cc/
  13. support/
  14. .bazelrc
  15. .gitignore
  16. BUILD
  17. Cargo.lock
  18. CODE_OF_CONDUCT
  19. CONTRIBUTING
  20. LICENSE
  21. MODULE.bazel
  22. README.md
  23. WORKSPACE.bzlmod
README.md

Crubit: C++/Rust Bidirectional Interop Tool

Build status

NOTE: Crubit currently expects deep integration with the build system, and is difficult to deploy to environments dissimilar to Google's monorepo. We do not have our tooling set up to accept external contributions at this time.

Crubit is a bidirectional bindings generator for C++ and Rust, with the goal of integrating the C++ and Rust ecosystems.

Status

Support for calling FFI-friendly C++ from Rust is in progress.

Support for calling Rust from C++ will arrive in 2024H2.

Example

Consider the following C++ function:

extern "C" bool IsGreater(int lhs, int rhs);

This function, if present in a header file which is processed by Crubit, becomes callable from Rust as if it were defined as:

pub fn IsGreater(lhs: ffi::c_int, rhs: ffi::c_int) -> bool {...}

Note: There are some temporary restrictions on the API shape. For example, functions that are not extern "C", or that accept a type like std::string, can't be called from Rust directly via Crubit. These restrictions will be relaxed over time.

Getting Started

Here are some resources for getting started with Crubit:

  • Rust Bindings for C++ Libraries is a detailed walkthrough on how to use C++ from Rust using Crubit.

  • The examples/cpp/ directory has copy-pastable examples of calling C++ from Rust, together with snapshots of what the generated Rust interface looks like.

Building Crubit

$ apt install clang lld bazel
$ git clone git@github.com:google/crubit.git
$ cd crubit
$ bazel build --linkopt=-fuse-ld=/usr/bin/ld.lld //rs_bindings_from_cc:rs_bindings_from_cc_impl

Using a prebuilt LLVM tree

$ git clone https://github.com/llvm/llvm-project
$ cd llvm-project
$ CC=clang CXX=clang++ cmake -S llvm -B build -DLLVM_ENABLE_PROJECTS='clang' -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=install
$ cmake --build build -j
$ # wait...
$ cmake --install build
$ cd ../crubit
$ LLVM_INSTALL_PATH=../llvm-project/install bazel build //rs_bindings_from_cc:rs_bindings_from_cc_impl