| commit | 36de572cf9e6827b88d6034b4d42b7549040f015 | [log] [tgz] |
|---|---|---|
| author | Lukasz Anforowicz <lukasza@google.com> | Fri Jun 16 08:17:44 2023 -0700 |
| committer | Copybara-Service <copybara-worker@google.com> | Fri Jun 16 08:18:16 2023 -0700 |
| tree | a1dfe307c817d621cccfe5771af9948c8e106184 | |
| parent | 73a79ab4615438f6a3d7eb305c6fee45c81769eb [diff] |
Replace `tcx.non_blanket_impls_for_ty(...)` with `tcx.associated_items(...)`. `non_blanket_impls_for_ty` doesn't work well for: 1. Traits with non-mandatory methods (like `Clone::clone_from` or `PartialEq::ne` where the default implementation is provided by the trait definition). Desire to support `Clone` in a follow-up CL is the main motivation for this CL. 2. Blanket impls. Because of the above this CL changes how `cc_bindings_from_rs` generates C-ABI thunks that call into a type/`Self`-specific implementation of a given trait method. Before this CL, the code would use `non_blanket_impls_for_ty` to iterate over `def_id`s of type/`Self`-*specialized* method `impl`s. After this CL, the code iterates over all trait methods reported by `associated_items` which helps by also covering methods with no specialized `impl`. OTOH this means that we now iterate over `Self`-*generic* methods and therefore need to substitute a specific `self_ty` as needed. This in turn means that we can't reuse `get_symbol_name` and `get_thunk_name` (because `Instance::mono` wouldn't work for `Self`-generic methods). This CL should have no impact on the current end-to-end behavior, because currently only the `Default` trait is supported and 1) it has only a single, mandatory method and 2) AFAIK it doesn't have any blanket impls. PiperOrigin-RevId: 540883898
Crubit is an experimental bidirectional bindings generator for C++ and Rust.
Please don‘t use, this is an experiment and we don’t yet know where will it take us. There will be breaking changes without warning. Unfortunately, we can't take contributions at this point.
Crubit allows for C++ code and Rust code to call each other without manually wrapping the APIs in an FFI-friendly interop layer. For example, a C++ function like this:
bool IsAbsPath(std::string_view path);
... becomes callable from Rust as if it were defined as:
pub fn IsAbsPath(path: std::string_view) -> bool {...}
Crubit automatically generates ABI-compatible bindings for structs (which can be passed both by value and by reference), functions, and methods, for a large variety of types. (Trivial types, nontrivial types, templated types, etc.)
$ 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
$ 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