[PATCH] D113391: [Modules] Don't support clang module and c++20 module at the same time

[Jan Svoboda via Phabricator via cfe-commits]

jansvoboda11 added inline comments.


================
Comment at: clang/test/ClangScanDeps/Inputs/header-search-pruning/cdb.json:1
-[
-  {
-    "directory": "DIR",
-    "command": "clang -E DIR/header-search-pruning.cpp -Ibegin -I1 -Ia -I3 -I4 -I5 -I6 -Ib -I8 -Iend DEFINES -fmodules -fcxx-modules -fmodules-cache-path=DIR/module-cache -fimplicit-modules -fmodule-map-file=DIR/module.modulemap",
-    "file": "DIR/header-search-pruning.cpp"
-  }
-]
+[{
+  "directory" : "DIR",
----------------
ChuanqiXu wrote:
> jansvoboda11 wrote:
> > Please undo the whitespace changes in `ClangScanDeps` tests.
> It looks like that it's formatted by clang-format surprisingly. I would undo this manually.
Thanks.


================
Comment at: clang/test/ClangScanDeps/Inputs/header-search-pruning/cdb.json:3
+  "directory" : "DIR",
+  "command" : "clang -E DIR/header-search-pruning.cpp -Ibegin -I1 -Ia -I3 -I4 -I5 -I6 -Ib -I8 -Iend DEFINES -fmodules -fmodules-cache-path=DIR/module-cache -fimplicit-modules -fmodule-map-file=DIR/module.modulemap",
+  "file" : "DIR/header-search-pruning.cpp"
----------------
ChuanqiXu wrote:
> jansvoboda11 wrote:
> > Can you explain why `-fcxx-modules` is removed? We want to explicitly enable Clang modules for C++ inputs here. That's off by default in our downstream repo and we'd like to keep this upstream to prevent conflicts. (it's benign upstream)
> According to the discussion in the link, I think it is in consensus that we decide to not support clang modules and c++20 modules at the same time. (I know many people may not have visited it. If any one disagree with the higher idea, I think it would be better to reply in that thread). 
> So the original test case would fail.
> 
> > We want to explicitly enable Clang modules for C++ inputs here. 
> 
> I am not sure if I missed any thing. Personally, it looks like the test now would test clang modules for c++ inputs. Since it has `-fmodule` option so that clang module is enabled and the input is C++ (from its suffix). Do I misunderstand you?
> According to the discussion in the link, I think it is in consensus that we decide to not support clang modules and c++20 modules at the same time. (I know many people may not have visited it. If any one disagree with the higher idea, I think it would be better to reply in that thread). 
> So the original test case would fail.

What's the error message? As I say, we're enabling Clang modules for C++ input here, not C++20 modules.

> > We want to explicitly enable Clang modules for C++ inputs here. 
> 
> I am not sure if I missed any thing. Personally, it looks like the test now would test clang modules for c++ inputs. Since it has `-fmodule` option so that clang module is enabled and the input is C++ (from its suffix). Do I misunderstand you?

Right. What I'm saying is that in our downstream repo, `-fmodules` is not enough to enable Clang modules for C++ inputs, you need to do it via `-fcxx-modules`. And we'd like to keep it upstream, even though it's benign here, to avoid conflicts between the repos.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D113391/new/

https://reviews.llvm.org/D113391