[all-commits] [llvm/llvm-project] eb70b3: Recommit [C++20] [Modules] [ClangScanDeps] Add Cla...

[Chuanqi Xu via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: eb70b38f838f6a3511dcbbc33f3ee81a4d05ede1
      https://github.com/llvm/llvm-project/commit/eb70b38f838f6a3511dcbbc33f3ee81a4d05ede1
  Author: Chuanqi Xu <yedeng.yd at linux.alibaba.com>
  Date:   2023-02-13 (Mon, 13 Feb 2023)

  Changed paths:
    M clang/include/clang/Tooling/DependencyScanning/DependencyScanningService.h
    M clang/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h
    M clang/include/clang/Tooling/DependencyScanning/DependencyScanningWorker.h
    M clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
    M clang/lib/Tooling/DependencyScanning/DependencyScanningTool.cpp
    M clang/lib/Tooling/DependencyScanning/DependencyScanningWorker.cpp
    M clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
    A clang/test/ClangScanDeps/P1689.cppm
    M clang/tools/clang-scan-deps/ClangScanDeps.cpp

  Log Message:
  -----------
  Recommit [C++20] [Modules] [ClangScanDeps] Add ClangScanDeps support for C++20 Named Modules in P1689 format (2/4)

Close https://github.com/llvm/llvm-project/issues/51792
Close https://github.com/llvm/llvm-project/issues/56770

This patch adds ClangScanDeps support for C++20 Named Modules in P1689
format. We can find the P1689 format at:
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p1689r5.html.
After we land the patch, we're able to compile C++20 Named
Modules with CMake! And although P1689 is written by kitware people,
other build systems should be able to use the format to compile C++20
Named Modules too.

TODO: Support header units in P1689 Format.
TODO2: Support C++20 Modules in the full dependency format of
ClangScanDeps. We also want to support C++20 Modules and clang modules
together according to
https://discourse.llvm.org/t/how-should-we-support-dependency-scanner-for-c-20-modules/66027.
But P1689 format cares about C++20 Modules only for now. So let's focus
on C++ Modules and P1689 format. And look at the full dependency format
later.

I'll add the ReleaseNotes and Documentations after the patch get landed.

Reviewed By: jansvoboda11

Differential Revision: https://reviews.llvm.org/D137527