Add a build rule which produces compile_commands.json for clangd

Author: SandSnip3r

.clangd

@@ -0,0 +1,9 @@
+# clangd configuration for the Bazel-driven C++ build.
+#
+# Requires a compile_commands.json at the workspace root. Generate it with:
+#     bazel run //:refresh_compile_commands
+#
+# See CONTRIBUTING.md ("Editor / clangd setup") for the full workflow.
+
+CompileFlags:
+  CompilationDatabase: .

.gitignore

@@ -82,3 +82,7 @@ coverage.xml
 *.pt2
 examples/torchtrt_aoti_example/torchtrt_aoti_example
 CLAUDE.md
+
+# clangd compilation database (generated by `bazel run //:refresh_compile_commands`)
+/compile_commands.json
+/external/

BUILD.bazel

@@ -1,3 +1,4 @@
+load("@hedron_compile_commands//:refresh_compile_commands.bzl", "refresh_compile_commands")
 load("@rules_pkg//:pkg.bzl", "pkg_tar", "pkg_zip")
 
 config_setting(
@@ -162,3 +163,21 @@ alias(
         "//conditions:default": ":libtorchtrt_runtime_tar",
     }),
 )
+
+# ---------------------------------------------------------------------------
+# Developer tooling
+# ---------------------------------------------------------------------------
+# Generates `compile_commands.json` at the workspace root for clangd-based
+# editors. Output is gitignored. Run on first checkout and after material
+# build-graph changes:
+#     bazel run //:refresh_compile_commands
+# See CONTRIBUTING.md ("Editor / clangd setup") for details.
+refresh_compile_commands(
+    name = "refresh_compile_commands",
+    tags = ["manual"],
+    targets = [
+        "//core/...",
+        "//cpp/...",
+        "//tests/...",
+    ],
+)

CONTRIBUTING.md

@@ -8,6 +8,18 @@ Do try to fill an issue with your feature or bug before filling a PR (op support
 
 Our build system relies on `bazel` (https://bazel.build/). Though there are many ways to install `bazel`, the preferred method is to use `bazelisk` (https://github.com/bazelbuild/bazelisk) which makes it simple to set up the correct version of bazel on the fly. Additional development dependencies can be installed via the `requirements-dev.txt` file.
 
+#### Editor / clangd setup (optional)
+
+For C++ code intelligence (go-to-definition, accurate diagnostics, completions) in any clangd-based editor — e.g. VSCode with the [clangd extension](https://marketplace.visualstudio.com/items?itemName=llvm-vs-code-extensions.vscode-clangd), Cursor, Neovim, Emacs — generate a Bazel-aware compilation database:
+
+```sh
+bazel run //:refresh_compile_commands
+```
+
+This writes `compile_commands.json` at the workspace root (gitignored). Re-run it after pulling changes that materially affect the build graph (new targets, new headers, dependency bumps). The repo's `.clangd` file picks up the database automatically.
+
+This is opt-in: developers who don't use clangd are unaffected, and the underlying `hedron_compile_commands` extractor is declared as a Bazel `dev_dependency`, so it does not enter the dep graph of consumers building against torch_tensorrt.
+
 #### Communication
 
 The primary location for discussion is GitHub issues and Github discussions. This is the best place for questions about the project and discussion about specific issues.

MODULE.bazel

@@ -23,6 +23,18 @@ git_override(
     remote = "https://github.com/narendasan/rules_pkg",
 )
 
+# Developer tooling: clangd-compatible compile_commands.json extractor.
+# `dev_dependency = True` keeps this out of the dep graph for any project that
+# consumes torch_tensorrt as a Bazel module. Refresh with:
+#     bazel run //:refresh_compile_commands
+# See CONTRIBUTING.md ("Editor / clangd setup") for details.
+bazel_dep(name = "hedron_compile_commands", dev_dependency = True)
+git_override(
+    module_name = "hedron_compile_commands",
+    remote = "https://github.com/hedronvision/bazel-compile-commands-extractor.git",
+    commit = "0e990032f3c5a866e72615cf67e5ce22186dcb97",
+)
+
 new_local_repository = use_repo_rule("@bazel_tools//tools/build_defs/repo:local.bzl", "new_local_repository")
 
 local_torch = use_repo_rule("//toolchains:local_torch.bzl", "local_torch")