[clang-tools-extra] [llvm] [clang-tidy] New check `misc-header-guard` (PR #177315)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE LINT COMMENT: clang-tidy-->


:warning: C/C++ code linter, clang-tidy found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

```bash

git diff -U0 origin/main...HEAD -- clang-tools-extra/clang-tidy/misc/HeaderGuardCheck.cpp clang-tools-extra/clang-tidy/misc/HeaderGuardCheck.h clang-tools-extra/clang-tidy/misc/MiscTidyModule.cpp |
python3 clang-tools-extra/clang-tidy/tool/clang-tidy-diff.py   -path build -p1 -quiet
```

</details>

<details>
<summary>
View the output from clang-tidy here.
</summary>

```


clang-tools-extra/clang-tidy/misc/HeaderGuardCheck.cpp:72:7: warning: class 'HeaderGuardCallbacks' can be moved into an anonymous namespace to enforce internal linkage [misc-use-internal-linkage]
   72 | class HeaderGuardCallbacks : public PPCallbacks {
      |       ^
```

</details>


https://github.com/llvm/llvm-project/pull/177315