[PATCH] D131062: [docs] Add "C++20 Modules"

[Chuanqi Xu via Phabricator via cfe-commits]

ChuanqiXu added inline comments.


================
Comment at: clang/docs/CPlusPlus20Modules.rst:377-393
+  │                                     │                                                            │                                │
+  ├─────────────  frontend ─────────────┼─────────────────────────  middle end ──────────────────────┼─────────── backend ────────────┤
+  │                                     │                                                            │                                │
+  └─── parsing ──── sema ──── codegen ──┴─── optimizations ─── IPO  ─── optimizations ─── codegen ───┴─── optimizations ─── codegen ──┘
+                                                                                                                                      
+  ┌───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+  │                                                                                                                                   │
----------------
I'm not sure if this could be rendered properly, if there is any suggestion?


================
Comment at: clang/docs/CPlusPlus20Modules.rst:585-587
+But according to [cpp.import](http://eel.is/c++draft/cpp.import#5),
+the import of header unit should export undefinition too.
+So the expected result of using header units here should be ``"Not defined."``.
----------------
@iains maybe we need to double check on this. I also filed an issue: https://github.com/llvm/llvm-project/issues/56899. My reading for `[cpp.import]p5` is `the point of undefinition` is also a macro definition, so we should emit it. But I maybe wrong. 

If I am wrong, I wish we could get an example to show differences (If any)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D131062/new/

https://reviews.llvm.org/D131062