[clang] [clang][modules] Optimize construction and usage of the submodule index (PR #113391)

Mon Oct 28 13:37:45 PDT 2024

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-x86_64-debian-dylib` running on `gribozavr4` while building `clang` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/60/builds/11233

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

```
Step 5 (build-unified-tree) failure: build (failure)
...
575.236 [115/21/6881] Building CXX object tools/lldb/source/Plugins/Language/CPlusPlus/CMakeFiles/lldbPluginCPlusPlusLanguage.dir/BlockPointer.cpp.o
575.412 [115/20/6882] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangUtilityFunction.cpp.o
575.722 [115/19/6883] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ASTStructExtractor.cpp.o
576.310 [115/18/6884] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangFunctionCaller.cpp.o
576.595 [115/17/6885] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ASTResultSynthesizer.cpp.o
577.216 [115/16/6886] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangUserExpression.cpp.o
577.314 [115/15/6887] Building CXX object tools/lldb/source/Plugins/SymbolFile/NativePDB/CMakeFiles/lldbPluginSymbolFileNativePDB.dir/UdtRecordCompleter.cpp.o
577.400 [115/14/6888] Building CXX object tools/lldb/source/Plugins/SymbolFile/PDB/CMakeFiles/lldbPluginSymbolFilePDB.dir/PDBASTParser.cpp.o
577.541 [115/13/6889] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/IRForTarget.cpp.o
577.696 [115/12/6890] Building CXX object tools/lldb/source/Plugins/TypeSystem/Clang/CMakeFiles/lldbPluginTypeSystemClang.dir/TypeSystemClang.cpp.o
FAILED: tools/lldb/source/Plugins/TypeSystem/Clang/CMakeFiles/lldbPluginTypeSystemClang.dir/TypeSystemClang.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes /usr/bin/ccache /usr/bin/clang++ -DGTEST_HAS_RTTI=0 -DHAVE_ROUND -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/1/llvm-x86_64-debian-dylib/build/tools/lldb/source/Plugins/TypeSystem/Clang -I/b/1/llvm-x86_64-debian-dylib/llvm-project/lldb/source/Plugins/TypeSystem/Clang -I/b/1/llvm-x86_64-debian-dylib/llvm-project/lldb/include -I/b/1/llvm-x86_64-debian-dylib/build/tools/lldb/include -I/b/1/llvm-x86_64-debian-dylib/build/include -I/b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/include -I/b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/../clang/include -I/b/1/llvm-x86_64-debian-dylib/build/tools/lldb/../clang/include -I/b/1/llvm-x86_64-debian-dylib/llvm-project/lldb/source -I/b/1/llvm-x86_64-debian-dylib/build/tools/lldb/source -isystem /usr/include/libxml2 -fPIC -fvisibility-inlines-hidden -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 -Wno-unknown-pragmas -Wno-strict-aliasing -Wno-vla-extension -O3 -DNDEBUG  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -std=c++17 -MD -MT tools/lldb/source/Plugins/TypeSystem/Clang/CMakeFiles/lldbPluginTypeSystemClang.dir/TypeSystemClang.cpp.o -MF tools/lldb/source/Plugins/TypeSystem/Clang/CMakeFiles/lldbPluginTypeSystemClang.dir/TypeSystemClang.cpp.o.d -o tools/lldb/source/Plugins/TypeSystem/Clang/CMakeFiles/lldbPluginTypeSystemClang.dir/TypeSystemClang.cpp.o -c /b/1/llvm-x86_64-debian-dylib/llvm-project/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
/b/1/llvm-x86_64-debian-dylib/llvm-project/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:1233:29: error: no viable overloaded '='
  std::tie(module, created) = m_module_map_up->findOrCreateModule(
  ~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/tuple:1173:7: note: candidate function not viable: no known conversion from 'clang::Module *' to 'const std::tuple<clang::Module *&, bool &>' for 1st argument
      operator=(typename conditional<__assignable<const _T1&, const _T2&>(),
      ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/tuple:1184:7: note: candidate function not viable: no known conversion from 'clang::Module *' to 'std::tuple<clang::Module *&, bool &>' for 1st argument
      operator=(typename conditional<__assignable<_T1, _T2>(),
      ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/tuple:1196:2: note: candidate template ignored: could not match 'tuple<type-parameter-0-0, type-parameter-0-1>' against 'clang::Module *'
        operator=(const tuple<_U1, _U2>& __in)
        ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/tuple:1206:2: note: candidate template ignored: could not match 'tuple<type-parameter-0-0, type-parameter-0-1>' against 'clang::Module *'
        operator=(tuple<_U1, _U2>&& __in)
        ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/tuple:1216:2: note: candidate template ignored: could not match 'pair<type-parameter-0-0, type-parameter-0-1>' against 'clang::Module *'
        operator=(const pair<_U1, _U2>& __in)
        ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/tuple:1227:2: note: candidate template ignored: could not match 'pair<type-parameter-0-0, type-parameter-0-1>' against 'clang::Module *'
        operator=(pair<_U1, _U2>&& __in)
        ^
1 error generated.
577.812 [115/11/6891] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangASTSource.cpp.o
578.583 [115/10/6892] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangASTImporter.cpp.o
578.907 [115/9/6893] Building CXX object tools/lldb/source/Plugins/SymbolFile/NativePDB/CMakeFiles/lldbPluginSymbolFileNativePDB.dir/PdbAstBuilder.cpp.o
579.091 [115/8/6894] Building CXX object tools/lldb/source/Plugins/SymbolFile/PDB/CMakeFiles/lldbPluginSymbolFilePDB.dir/SymbolFilePDB.cpp.o
579.616 [115/7/6895] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangModulesDeclVendor.cpp.o
579.642 [115/6/6896] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangExpressionDeclMap.cpp.o
580.001 [115/5/6897] Building CXX object tools/lldb/source/Plugins/SymbolFile/DWARF/CMakeFiles/lldbPluginSymbolFileDWARF.dir/DWARFASTParserClang.cpp.o
580.120 [115/4/6898] Building CXX object tools/lldb/source/Commands/CMakeFiles/lldbCommands.dir/CommandObjectTarget.cpp.o
581.577 [115/3/6899] Building CXX object tools/lldb/source/Plugins/SymbolFile/NativePDB/CMakeFiles/lldbPluginSymbolFileNativePDB.dir/SymbolFileNativePDB.cpp.o
582.059 [115/2/6900] Building CXX object tools/lldb/source/Plugins/ExpressionParser/Clang/CMakeFiles/lldbPluginExpressionParserClang.dir/ClangExpressionParser.cpp.o
582.721 [115/1/6901] Building CXX object tools/lldb/source/Plugins/SymbolFile/DWARF/CMakeFiles/lldbPluginSymbolFileDWARF.dir/SymbolFileDWARF.cpp.o
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/113391