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behnamasadibehnamasadi
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clang tidy added
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‎CMakeLists.txt‎

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add_executable(main src/main.cpp)
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endif()
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message("\n########################################## clang-format ##########################################\n")
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find_program(CLANG_FORMAT_EXECUTABLE NAMES clang-format clang-format-18 clang-format-17 clang-format-16 clang-format-15)
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if(CLANG_FORMAT_EXECUTABLE)
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execute_process(
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COMMAND ${CLANG_FORMAT_EXECUTABLE} --version
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OUTPUT_VARIABLE CLANG_FORMAT_VERSION
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OUTPUT_STRIP_TRAILING_WHITESPACE
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)
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message(STATUS "clang-format found: ${CLANG_FORMAT_EXECUTABLE}")
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message(STATUS "clang-format version: ${CLANG_FORMAT_VERSION}")
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else()
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message(WARNING "clang-format is not installed. Install it to enable format-on-save in VS Code.\n"
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" Ubuntu/Debian: sudo apt install clang-format\n"
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" macOS: brew install clang-format\n"
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" Windows: choco install llvm (or install LLVM from https://releases.llvm.org)")
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endif()
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message("\n########################################## clang-tidy ##########################################\n")
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find_program(CLANG_TIDY_EXECUTABLE NAMES clang-tidy clang-tidy-18 clang-tidy-17 clang-tidy-16 clang-tidy-15)
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if(CLANG_TIDY_EXECUTABLE)
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execute_process(
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COMMAND ${CLANG_TIDY_EXECUTABLE} --version
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OUTPUT_VARIABLE CLANG_TIDY_VERSION
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OUTPUT_STRIP_TRAILING_WHITESPACE
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)
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message(STATUS "clang-tidy found: ${CLANG_TIDY_EXECUTABLE}")
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message(STATUS "clang-tidy version:\n${CLANG_TIDY_VERSION}")
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else()
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message(WARNING "clang-tidy is not installed. Install it to enable static analysis / linting.\n"
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" Ubuntu/Debian: sudo apt install clang-tidy\n"
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" macOS: brew install llvm (clang-tidy ships with LLVM)\n"
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" Windows: choco install llvm (or install LLVM from https://releases.llvm.org)")
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endif()
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message("\n########################################## System Design ##########################################\n")
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add_executable(reusable_library src/reusable_library.cpp)

‎README.md‎

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- [Goolge C++ Style Guide](https://google.github.io/styleguide/cppguide.html)
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- [isocpp](https://isocpp.org/wiki/faq/coding-standards)
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- [Bjarne Stroustrup's C++ Style](https://www.stroustrup.com/bs_faq2.html)
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- [Static analysis and linting with clang-tidy](docs/clang_tidy.md)
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## [C++ System Design](#)
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‎docs/clang_tidy.md‎

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# clang-tidy
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`clang-tidy` is a static analyzer / linter for C and C++ that ships with LLVM. It reads your code without running it and flags problems — many of which it can also auto-fix.
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It is **not** the same as `clang-format`:
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| | clang-format | clang-tidy |
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|---|---|---|
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| Touches | Whitespace, line breaks, indentation | Code logic, names, idioms |
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| Speed | Instant | Slower (semantic analysis) |
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| Needs build info? | No | Yes (`compile_commands.json`) |
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| Auto-fix | Always | Often (with `-fix`) |
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## Installation
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**Ubuntu / Debian**
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```
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sudo apt install clang-tidy
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```
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**macOS**
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```
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brew install llvm
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```
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**Windows**
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```
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choco install llvm
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```
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or download LLVM from https://releases.llvm.org
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Verify:
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```
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clang-tidy --version
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```
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## What it catches
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Checks are grouped into categories. A few examples from each:
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| Category | Check | What it catches |
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|---|---|---|
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| `bugprone-*` | `bugprone-use-after-move` | Using a variable after `std::move` |
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| `modernize-*` | `modernize-use-nullptr` | Replaces `NULL` / `0` with `nullptr` |
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| `modernize-*` | `modernize-use-auto` | `std::vector<int>::iterator it` → `auto it` |
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| `modernize-*` | `modernize-loop-convert` | Index `for` loops → range-for |
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| `performance-*` | `performance-unnecessary-copy-initialization` | `auto x = vec[0];` when `const auto&` suffices |
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| `performance-*` | `performance-for-range-copy` | `for (auto x : container)` should be `const auto&` |
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| `readability-*` | `readability-identifier-naming` | Enforce `snake_case` / `CamelCase` |
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| `cppcoreguidelines-*` | `cppcoreguidelines-pro-type-member-init` | Uninitialized members |
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| `cert-*` | `cert-err58-cpp` | CERT secure coding violations |
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| `clang-analyzer-*` | path-sensitive analysis | Null derefs, leaks, use-after-free |
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Full list: https://clang.llvm.org/extra/clang-tidy/checks/list.html
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## Generate `compile_commands.json`
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clang-tidy needs to know each file's include paths, defines, and C++ standard. CMake produces this automatically:
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```cmake
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set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
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```
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After configuring, the file appears in your build directory. Symlink it to the project root so clang-tidy finds it:
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```
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ln -s build/compile_commands.json compile_commands.json
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```
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## Running clang-tidy
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**One file**
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```
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clang-tidy src/main.cpp
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```
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**Pick specific checks**
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```
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clang-tidy --checks='-*,modernize-*,performance-*,bugprone-*' src/main.cpp
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```
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**Apply suggested fixes**
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```
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clang-tidy -fix src/main.cpp
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```
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**Run on every file in a directory**
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```
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find src -name '*.cpp' | xargs clang-tidy
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```
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## `.clang-tidy` config file
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Place a `.clang-tidy` file at the project root to make checks consistent across the team:
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```yaml
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Checks: >
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-*,
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bugprone-*,
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modernize-*,
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performance-*,
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readability-*,
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cppcoreguidelines-*,
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-modernize-use-trailing-return-type,
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-readability-identifier-length
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WarningsAsErrors: ''
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HeaderFilterRegex: '.*'
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FormatStyle: file
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```
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- `Checks` — comma-separated list. `-*` disables all, then re-enables groups. Prefix a check with `-` to silence it.
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- `WarningsAsErrors` — set to the same expression to fail builds on warnings.
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- `HeaderFilterRegex` — which headers to analyze (default skips system headers).
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- `FormatStyle: file` — apply `clang-format` to fix-ups using your `.clang-format`.
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## Run via CMake on every build
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Add to `CMakeLists.txt`:
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```cmake
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set(CMAKE_CXX_CLANG_TIDY clang-tidy)
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```
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Now every translation unit is linted as it compiles. Combine with the detection block already in this project's CMake:
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```cmake
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find_program(CLANG_TIDY_EXECUTABLE NAMES clang-tidy)
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if(CLANG_TIDY_EXECUTABLE)
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set(CMAKE_CXX_CLANG_TIDY ${CLANG_TIDY_EXECUTABLE})
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endif()
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```
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## VS Code integration
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The **clangd** extension (`llvm-vs-code-extensions.vscode-clangd`) runs clang-tidy diagnostics inline as you type. With clangd installed:
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```json
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{
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"clangd.arguments": [
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"--clang-tidy",
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"--compile-commands-dir=build"
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]
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}
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```
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The C/C++ extension (`ms-vscode.cpptools`) also has built-in clang-tidy support — enable `C_Cpp.codeAnalysis.clangTidy.enabled` in settings.
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## CI integration
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Run on changed files only in pull requests:
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```
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git diff --name-only origin/master...HEAD | grep -E '\.(cpp|h|hpp)$' | xargs clang-tidy -p build
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```
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Fail the job if any warnings appear:
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```
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clang-tidy --warnings-as-errors='*' -p build src/main.cpp
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```
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## Common gotchas
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- **"unable to find compile_commands.json"** — pass `-p path/to/build` or symlink it to project root.
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- **Slow runs** — clang-tidy reparses each TU; on large projects use `run-clang-tidy.py` (ships with LLVM) for parallel execution.
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- **Fix conflicts** — when two checks suggest overlapping edits, run clang-tidy multiple times until output is stable.
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- **Generated / third-party code** — exclude with `HeaderFilterRegex` or wrap in `// NOLINT` / `// NOLINTNEXTLINE` comments.
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## Suppressing a single warning
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```cpp
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int x; // NOLINT(cppcoreguidelines-init-variables)
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// NOLINTNEXTLINE(modernize-use-nullptr)
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foo(0);
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```
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## References
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- Official docs: https://clang.llvm.org/extra/clang-tidy/
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- Check list: https://clang.llvm.org/extra/clang-tidy/checks/list.html
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- `run-clang-tidy.py`: https://github.com/llvm/llvm-project/blob/main/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py

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