[libc-commits] [libc] [libc][clang-tidy] Add llvm-header-guard to get consistant naming and prevent file copy/paste issues. (PR #66477)

[Siva Chandra via libc-commits]

sivachandra wrote:

This SGTM. We could have done this earlier but there were a few exceptions that we had to deal with so we punted on this, example the `include` directory. But, what you are proposing is of a much lower scope (restricted to the `src` directory) so go ahead.

https://github.com/llvm/llvm-project/pull/66477