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

[Bret Brown via cfe-commits]

bretbrownjr wrote:

I highly recommend talking to @mathstuf of the CMake project about a way for the build system can emit a next generation set of build graph metadata (think modules appropriate compile commands, including dependencies).

I expect it will be more efficient for the build system, compiler, and LSP to all work together compared to implementing large subsets of a build system in the clangd LSP.

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