[clang] [clang][deps] Implement efficient in-process `ModuleCache` (PR #129751)

Wed Mar 19 03:43:54 PDT 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-ppc64-aix` running on `aix-ppc64` while building `clang` at step 3 "clean-build-dir".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/64/builds/2529

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 3 (clean-build-dir) failure: Delete failed. (failure) (timed out)
Step 5 (build-unified-tree) failure: build (failure)
...
5226.823 [870/10/4445] Building CXX object tools/clang/lib/Tooling/Refactoring/CMakeFiles/obj.clangToolingRefactoring.dir/RefactoringActions.cpp.o
5228.140 [869/10/4446] Building CXX object tools/clang/lib/Tooling/Syntax/CMakeFiles/obj.clangToolingSyntax.dir/TokenBufferTokenManager.cpp.o
5229.895 [868/10/4447] Building CXX object tools/clang/lib/Tooling/Syntax/CMakeFiles/obj.clangToolingSyntax.dir/Mutations.cpp.o
5230.440 [867/10/4448] Building CXX object tools/clang/lib/Tooling/Refactoring/CMakeFiles/obj.clangToolingRefactoring.dir/Rename/RenamingAction.cpp.o
5233.464 [866/10/4449] Building CXX object tools/clang/lib/Tooling/Syntax/CMakeFiles/obj.clangToolingSyntax.dir/Tree.cpp.o
5235.404 [865/10/4450] Building CXX object tools/clang/lib/Tooling/Syntax/CMakeFiles/obj.clangToolingSyntax.dir/Synthesis.cpp.o
5237.086 [864/10/4451] Building CXX object tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/DependencyScanningFilesystem.cpp.o
5237.596 [863/10/4452] Building CXX object tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/DependencyScanningService.cpp.o
5238.530 [862/10/4453] Building CXX object tools/clang/lib/Tooling/Syntax/CMakeFiles/obj.clangToolingSyntax.dir/Tokens.cpp.o
5240.446 [861/10/4454] Building CXX object tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/InProcessModuleCache.cpp.o
FAILED: tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/InProcessModuleCache.cpp.o 
/usr/local/clang-17.0.2/bin/clang++ -DCLANG_EXPORTS -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_LARGE_FILE_API -D_XOPEN_SOURCE=700 -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/build/tools/clang/lib/Tooling/DependencyScanning -I/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/llvm-project/clang/lib/Tooling/DependencyScanning -I/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/llvm-project/clang/include -I/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/build/tools/clang/include -I/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/build/include -I/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/llvm-project/llvm/include -mcmodel=large -fPIC -Werror -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -fno-common -Woverloaded-virtual -Wno-nested-anon-types -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -pthread -MD -MT tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/InProcessModuleCache.cpp.o -MF tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/InProcessModuleCache.cpp.o.d -o tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/InProcessModuleCache.cpp.o -c /home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/llvm-project/clang/lib/Tooling/DependencyScanning/InProcessModuleCache.cpp
/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/llvm-project/clang/lib/Tooling/DependencyScanning/InProcessModuleCache.cpp:38:5: error: 'shared_lock' may not intend to support class template argument deduction [-Werror,-Wctad-maybe-unsupported]
   38 |     std::shared_lock Lock(*OwningLock.mutex());
      |     ^
/opt/IBM/openxlCSDK/include/c++/v1/shared_mutex:311:7: note: add a deduction guide to suppress this warning
  311 | class shared_lock
      |       ^
/home/powerllvm/powerllvm_env/aix-ppc64/clang-ppc64-aix/llvm-project/clang/lib/Tooling/DependencyScanning/InProcessModuleCache.cpp:68:7: error: 'lock_guard' may not intend to support class template argument deduction [-Werror,-Wctad-maybe-unsupported]
   68 |       std::lock_guard Lock(Mutexes.Mutex);
      |       ^
/opt/IBM/openxlCSDK/include/c++/v1/__mutex_base:83:1: note: add a deduction guide to suppress this warning
   83 | lock_guard
      | ^
2 errors generated.
5246.529 [861/9/4455] Building CXX object tools/clang/lib/Tooling/Refactoring/CMakeFiles/obj.clangToolingRefactoring.dir/ASTSelection.cpp.o
5260.793 [861/8/4456] Building CXX object tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/DependencyScanningTool.cpp.o
5262.619 [861/7/4457] Building CXX object tools/clang/lib/Tooling/Refactoring/CMakeFiles/obj.clangToolingRefactoring.dir/Rename/USRFindingAction.cpp.o
5263.649 [861/6/4458] Building CXX object tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/DependencyScanningWorker.cpp.o
5264.535 [861/5/4459] Building CXX object tools/clang/lib/Tooling/ASTDiff/CMakeFiles/obj.clangToolingASTDiff.dir/ASTDiff.cpp.o
5269.912 [861/4/4460] Building CXX object tools/clang/lib/Tooling/Refactoring/CMakeFiles/obj.clangToolingRefactoring.dir/Rename/USRFinder.cpp.o
5270.853 [861/3/4461] Building CXX object tools/clang/lib/Tooling/DependencyScanning/CMakeFiles/obj.clangDependencyScanning.dir/ModuleDepCollector.cpp.o
5271.601 [861/2/4462] Building CXX object tools/clang/lib/Tooling/Syntax/CMakeFiles/obj.clangToolingSyntax.dir/BuildTree.cpp.o
5271.876 [861/1/4463] Building CXX object tools/clang/lib/Tooling/Refactoring/CMakeFiles/obj.clangToolingRefactoring.dir/Rename/USRLocFinder.cpp.o
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/129751