[clang] [Preprocessor] Do not expand macros if the input is already preprocessed (PR #137665)

[Aaron Ballman via cfe-commits]

Juan Manuel Martinez =?utf-8?q?Caamaño?= <juamarti at amd.com>,
Juan Manuel Martinez =?utf-8?q?Caamaño?= <juamarti at amd.com>,
Juan Manuel Martinez =?utf-8?q?Caamaño?Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/137665 at github.com>


https://github.com/AaronBallman approved this pull request.

A nit and a question for the modules maintainers, but otherwise I think this looks good to me. Please don't land until @Bigcheese or @ChuanqiXu9 have had a chance to weigh in on the modules test question.

https://github.com/llvm/llvm-project/pull/137665