Clangd, clang-format, and clang-tidy are required to be in distribution since 1.4.0

[scasagrande]

Problem

Updating from 1.3.0 to 1.4.0 requires an llvm distribution that contains clangd, clang-format, and clang-tidy

Example error output:

ERROR: /home/runner/.cache/bazel/_bazel_runner/05e35152b9f4d639f0caf72c58272633/sandbox/processwrapper-sandbox/1/execroot/_main/_tmp/20b0fbcfb3bd545ee034011c9840c284/_bazel_runner/3a2f3221680ba9580bde03029baa3e75/external/rules_rust++i+rules_rust_tinyjson/BUILD.bazel:4:37: Compiling Rust (without process_wrapper) rlib tinyjson (4 files) [for tool] failed: missing input file '@@toolchains_llvm++llvm+llvm_toolchain//:bin/clang-format'
ERROR: /home/runner/.cache/bazel/_bazel_runner/05e35152b9f4d639f0caf72c58272633/sandbox/processwrapper-sandbox/1/execroot/_main/_tmp/20b0fbcfb3bd545ee034011c9840c284/_bazel_runner/3a2f3221680ba9580bde03029baa3e75/external/rules_rust++i+rules_rust_tinyjson/BUILD.bazel:4:37: Compiling Rust (without process_wrapper) rlib tinyjson (4 files) [for tool] failed: missing input file '@@toolchains_llvm++llvm+llvm_toolchain//:bin/clang-tidy'
ERROR: /home/runner/.cache/bazel/_bazel_runner/05e35152b9f4d639f0caf72c58272633/sandbox/processwrapper-sandbox/1/execroot/_main/_tmp/20b0fbcfb3bd545ee034011c9840c284/_bazel_runner/3a2f3221680ba9580bde03029baa3e75/external/rules_rust++i+rules_rust_tinyjson/BUILD.bazel:4:37: Compiling Rust (without process_wrapper) rlib tinyjson (4 files) [for tool] failed: missing input file '@@toolchains_llvm++llvm+llvm_toolchain//:bin/clangd'
ERROR: /home/runner/.cache/bazel/_bazel_runner/05e35152b9f4d639f0caf72c58272633/sandbox/processwrapper-sandbox/1/execroot/_main/_tmp/20b0fbcfb3bd545ee034011c9840c284/_bazel_runner/3a2f3221680ba9580bde03029baa3e75/external/rules_rust++i+rules_rust_tinyjson/BUILD.bazel:4:37: Compiling Rust (without process_wrapper) rlib tinyjson (4 files) [for tool] failed: 3 input file(s) do not exist

Likely cause

https://github.com/bazel-contrib/toolchains_llvm/pull/463

Prior to this pr, clang-format and clang-tidy were available via @llvm_toolchain_llvm//:bin/clang-format and @llvm_toolchain_llvm//:bin/clang-tidy, but were not requirements.

Discussion

If this is what we want, we should update document this and update some common "slimmer" llvm distributions, such as:

• https://steven.casagrande.io/posts/2024/building-macos-llvm-package/
• https://github.com/MaterializeInc/toolchains
• https://github.com/dzbarsky/static-clang

[fmeum]

Instead of documenting additional requirements, we should probably just make the logic at https://github.com/bazel-contrib/toolchains_llvm/blob/4c3d6cfc62d4639106d807476aa1702dfc2c884b/toolchain/internal/configure.bzl#L125-L130 more intelligent by testing for existence. Would you be interested in sending a PR for this?

[scasagrande]

Sure, I'll take a look this week

[darkrift]

@scasagrande have you had time to check this out ? We just faced this issue last week because we also use static-clang from dzbarsky.

While static-clang has a trick to add empty binaries in their archive, this would be an even better fix so that the tools are dynamic according to the pulled distribution

[scasagrande]

Here was my first attempt, but it doesn't work: https://github.com/bazel-contrib/toolchains_llvm/pull/483

See the comments as to why

[scasagrande]

I'm actually a confused as to why clang-format and clang-tidy were added in #463 when they were previously accessible via @llvm_toolchain_llvm//:clang-format and @llvm_toolchain_llvm//:clang-tidy https://github.com/bazel-contrib/toolchains_llvm/blob/23721c98423f4e467236709e1e75b43b3cdfc3cf/toolchain/BUILD.llvm_repo#L149-L157

and clangd should be accessible via the general export: https://github.com/bazel-contrib/toolchains_llvm/blob/23721c98423f4e467236709e1e75b43b3cdfc3cf/toolchain/BUILD.llvm_repo#L20