cpp-linter-hooks: The Most Complete pre-commit Solution for C/C++ Projects

#cpp #c #showdev #productivity

If you work on Python projects, you've probably used pre-commit — running black, ruff, mypy before every git commit, blocking anything that doesn't meet the standard. This workflow is well-established in the Python ecosystem.

For C/C++ projects, it's a different story.

The official mirrors-clang-format hook only handles formatting. If you want clang-tidy for static analysis, you're on your own. Features like compilation database auto-detection, version pinning, or auto-fix? Not even on the radar.

cpp-linter-hooks fills this gap. It provides both clang-format and clang-tidy hooks in a single pre-commit repo, along with the supporting capabilities that C/C++ projects actually need.

Why Not Just Use mirrors-clang-format?

Here's a quick comparison:

Feature	cpp-linter-hooks	mirrors-clang-format
clang-format	✅	✅
clang-tidy	✅	❌
Inline style string (`--style`)	✅	❌
Tool version pinning (`--version`)	✅	❌ (via rev tag)
Custom `.clang-tidy` config	✅	❌
Compilation database auto-detection	✅	❌
Dry-run mode	✅	❌
Auto-fix (`--fix` for clang-tidy)	✅	❌
Verbose output	✅	❌
Parallel execution (`--jobs`)	✅	❌

mirrors-clang-format does one thing: download a clang-format binary and run it on changed files. If formatting is all you need, it works fine.

But in real-world C/C++ projects, the true headache isn't inconsistent formatting — it's clang-tidy diagnostics: memory leaks, undefined behavior, performance pitfalls. These are exactly the issues worth catching at commit time.

Quick Start

Add this to your .pre-commit-config.yaml:

repos:
  - repo: https://github.com/cpp-linter/cpp-linter-hooks
    rev: v1.4.1
    hooks:
      - id: clang-format
        args: [--style=file]
      - id: clang-tidy
        args: [--checks=.clang-tidy]

Then:

pre-commit install
pre-commit run --all-files

The first run downloads the clang tools from PyPI. Subsequent runs use the cached environment.

Practical Configuration Details

Pin Your Tool Version

An easy detail to miss: rev is the project version of cpp-linter-hooks, not the clang tool version. Without an explicit version, upgrading rev may silently change your clang-format or clang-tidy version, leading to inconsistent results across your team.

Always add --version:

- id: clang-format
  args: [--style=file, --version=21]
- id: clang-tidy
  args: [--checks=.clang-tidy, --version=21]

This locks the tool at clang 21 regardless of project rev upgrades.

Compilation Database

clang-tidy needs compiler flags for accurate static analysis. If your project uses CMake or Meson, generate compile_commands.json and cpp-linter-hooks auto-detects it from common build directories (build/, out/, cmake-build-debug/, etc.) — no extra configuration needed.

You can also specify it explicitly:

- id: clang-tidy
  args: [--compile-commands=build, --checks=.clang-tidy]

To generate the compilation database:

cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=ON -Bbuild .

Auto-Fix

clang-tidy's --fix can auto-apply fixes for certain checks. cpp-linter-hooks supports this since v1.4.0, but it's opt-in — auto-modifying source code carries risk, and you should decide whether you trust it.

- id: clang-tidy
  args: [--checks=.clang-tidy, --fix]

Note: enabling --fix automatically disables parallel execution (--jobs) to prevent concurrent writes to the same header file.

Performance

Running full clang-tidy on a large codebase can be slow. Two ways to optimize:

Limit scope with the files filter:

- id: clang-tidy
  args: [--checks=.clang-tidy, --version=21]
  files: ^(src|include)/.*\.(cpp|cc|cxx|h|hpp)$

Enable parallelism:

- id: clang-tidy
  args: [--checks=.clang-tidy, --jobs=4]

For day-to-day development, you can also check only changed files:

pre-commit run --files $(git diff --name-only)

Relationship with cpp-linter-action

If you've looked into C/C++ CI tooling, you might have seen cpp-linter-action (139 stars on GitHub Marketplace). It's a GitHub Action that runs clang-format and clang-tidy in CI pipelines and surfaces results as file annotations, thread comments, and PR reviews.

cpp-linter-hooks and cpp-linter-action are two complementary tools under the same organization:

cpp-linter-action: runs in CI, designed for the PR review workflow
cpp-linter-hooks: runs locally before git commit, designed for daily development

Both share the same .clang-format and .clang-tidy configuration files. Code that passes locally won't break in CI — a classic "local + CI dual-gate" pattern.

Wrapping Up

cpp-linter-hooks is one of the main projects I maintain under the cpp-linter organization. Since 2022, it has grown to include version pinning, compilation database detection, auto-fix, and parallel execution — covering the core needs of C/C++ projects at the pre-commit stage.

If you develop in C/C++ or maintain a C/C++ open-source project, give it a try. Add it to your .pre-commit-config.yaml, and within minutes you'll have automatic formatting and static analysis running before every commit — no more waiting for CI to go red before fixing things.