[clang-tools-extra] [clangd] [C++20] [Modules] Introduce initial support for C++20 Modules (PR #66462)

[Chuanqi Xu via cfe-commits]

ChuanqiXu9 wrote:

The bot shows some escaping code issue on windows:

>  YAML:6:44: error: Unrecognized escape code
> --
>   | "file": "C:\Users\ContainerAdministrator\AppData\Local\Temp\lit-tmp-ns06ti05\modules-test-e111b6/foo.cppm",

And I'm like to skip the tests on windows temporarily since I don't have a windows development. I hope someone else can fix it later and I feel it may not be too hard. 



https://github.com/llvm/llvm-project/pull/66462