[llvm] Introduce a new CMake option to test LLVM_WINDOWS_PREFER_FORWARD_SLASH behaviors (PR #207194)

[via llvm-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 133416 tests passed
* 3502 tests skipped

All executed tests passed, but another part of the build **failed**. Click on a failure below to see the details.

<details>
<summary>[code=4294967295] tools/clang/tools/extra/clangd/unittests/ClangdTests.exe</summary>

```
FAILED: [code=4294967295] tools/clang/tools/extra/clangd/unittests/ClangdTests.exe
C:\Windows\system32\cmd.exe /C "cd . && C:\BuildTools\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin\cmake.exe -E vs_link_exe --msvc-ver=1944 --intdir=tools\clang\tools\extra\clangd\unittests\CMakeFiles\ClangdTests.dir --rc="C:\Program Files (x86)\Windows Kits\10\bin\10.0.26100.0\x64\rc.exe" --mt="C:\Program Files (x86)\Windows Kits\10\bin\10.0.26100.0\x64\mt.exe" --manifests  -- C:\clang\clang-msvc\bin\lld-link.exe /nologo @CMakeFiles\ClangdTests.rsp  /out:tools\clang\tools\extra\clangd\unittests\ClangdTests.exe /implib:tools\clang\tools\extra\clangd\unittests\ClangdTests.lib /pdb:tools\clang\tools\extra\clangd\unittests\ClangdTests.pdb /version:0.0 /MANIFEST:NO /Brepro /INCREMENTAL:NO /subsystem:console  /STACK:10000000 && cd ."
LINK: command "C:\clang\clang-msvc\bin\lld-link.exe /nologo @CMakeFiles\ClangdTests.rsp /out:tools\clang\tools\extra\clangd\unittests\ClangdTests.exe /implib:tools\clang\tools\extra\clangd\unittests\ClangdTests.lib /pdb:tools\clang\tools\extra\clangd\unittests\ClangdTests.pdb /version:0.0 /MANIFEST:NO /Brepro /INCREMENTAL:NO /subsystem:console /STACK:10000000" failed (exit code 1) with the following output:
lld-link: error: undefined symbol: private: void __cdecl clang::ento::PathPieces::flattenTo(class clang::ento::PathPieces &, class clang::ento::PathPieces &, bool) const
>>> referenced by clangTidy.lib(ClangTidy.cpp.obj):(public: virtual void __cdecl clang::tidy::`anonymous namespace'::AnalyzerDiagnosticConsumer::FlushDiagnosticsImpl(class std::vector<class clang::ento::PathDiagnostic const *, class std::allocator<class clang::ento::PathDiagnostic const *>> &, class tidy::ento::PathDiagnosticConsumer::FilesMade *))
>>> referenced by clangStaticAnalyzerCore.lib(TextDiagnostics.cpp.obj):(public: virtual void __cdecl `anonymous namespace'::TextDiagnostics::FlushDiagnosticsImpl(class std::vector<class clang::ento::PathDiagnostic const *, class std::allocator<class clang::ento::PathDiagnostic const *>> &, class clang::ento::PathDiagnosticConsumer::FilesMade *))
>>> referenced by clangStaticAnalyzerCore.lib(HTMLDiagnostics.cpp.obj):(public: virtual void __cdecl `anonymous namespace'::HTMLDiagnostics::FlushDiagnosticsImpl(class std::vector<class clang::ento::PathDiagnostic const *, class std::allocator<class clang::ento::PathDiagnostic const *>> &, class clang::ento::PathDiagnosticConsumer::FilesMade *))
>>> referenced 2 more times

lld-link: error: undefined symbol: public: virtual __cdecl clang::ento::PathDiagnosticConsumer::~PathDiagnosticConsumer(void)
>>> referenced by clangTidy.lib(ClangTidy.cpp.obj):(public: virtual void * __cdecl clang::tidy::`anonymous namespace'::AnalyzerDiagnosticConsumer::`scalar deleting dtor'(unsigned int))
>>> referenced by clangStaticAnalyzerCore.lib(PlistDiagnostics.cpp.obj):(public: virtual void * __cdecl `anonymous namespace'::PlistDiagnostics::`scalar deleting dtor'(unsigned int))
>>> referenced by clangStaticAnalyzerCore.lib(TextDiagnostics.cpp.obj):(public: virtual void * __cdecl `anonymous namespace'::TextDiagnostics::`scalar deleting dtor'(unsigned int))
>>> referenced 2 more times

lld-link: error: undefined symbol: private: virtual void __cdecl clang::ento::PathDiagnosticConsumer::anchor(void)
>>> referenced by clangTidy.lib(ClangTidy.cpp.obj):(const clang::tidy::`anonymous namespace'::AnalyzerDiagnosticConsumer::`vftable')
>>> referenced by clangTidy.lib(ClangTidy.cpp.obj):(const clang::ento::PathDiagnosticConsumer::`vftable')
>>> referenced by clangStaticAnalyzerCore.lib(PlistDiagnostics.cpp.obj):(const `anonymous namespace'::PlistDiagnostics::`vftable')
>>> referenced 3 more times

lld-link: error: undefined symbol: void __cdecl clang::threadSafety::threadSafetyCleanup(class clang::threadSafety::BeforeSet *)
>>> referenced by clangSema.lib(Sema.cpp.obj):(public: __cdecl clang::Sema::~Sema(void))

lld-link: error: undefined symbol: public: __cdecl clang::MacroExpansionContext::MacroExpansionContext(class clang::LangOptions const &)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(class std::unique_ptr<class clang::ento::AnalysisASTConsumer, struct std::default_delete<class clang::ento::AnalysisASTConsumer>> __cdecl clang::ento::CreateAnalysisConsumer(class clang::CompilerInstance &))

lld-link: error: undefined symbol: public: void __cdecl clang::MacroExpansionContext::registerForPreprocessor(class clang::Preprocessor &)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(class std::unique_ptr<class clang::ento::AnalysisASTConsumer, struct std::default_delete<class clang::ento::AnalysisASTConsumer>> __cdecl clang::ento::CreateAnalysisConsumer(class clang::CompilerInstance &))

lld-link: error: undefined symbol: public: __cdecl clang::CallGraph::CallGraph(void)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: virtual void __cdecl `anonymous namespace'::AnalysisConsumer::HandleTranslationUnit(class clang::ASTContext &))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::IssueWarnings(class clang::TranslationUnitDecl *))
>>> referenced by clangScalableStaticAnalysisAnalyses.lib(CallGraphExtractor.cpp.obj):(private: virtual void __cdecl `anonymous namespace'::CallGraphExtractor::HandleTranslationUnit(class clang::ASTContext &))
>>> referenced 5 more times

lld-link: error: undefined symbol: public: virtual __cdecl clang::CallGraph::~CallGraph(void)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: virtual void __cdecl `anonymous namespace'::AnalysisConsumer::HandleTranslationUnit(class clang::ASTContext &))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::IssueWarnings(class clang::TranslationUnitDecl *))
>>> referenced by clangScalableStaticAnalysisAnalyses.lib(CallGraphExtractor.cpp.obj):(private: virtual void __cdecl `anonymous namespace'::CallGraphExtractor::HandleTranslationUnit(class clang::ASTContext &))
>>> referenced 5 more times

lld-link: error: undefined symbol: public: void __cdecl clang::AnalysisDeclContextManager::clear(void)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))

lld-link: error: undefined symbol: public: class clang::AnalysisDeclContext * __cdecl clang::AnalysisDeclContextManager::getContext(class clang::Decl const *)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced 40 more times

lld-link: error: undefined symbol: public: bool __cdecl clang::AnalysisDeclContext::isBodyAutosynthesized(void) const
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerCore.lib(BugReporter.cpp.obj):(public: virtual void __cdecl clang::ento::PathSensitiveBugReporter::emitReport(class std::unique_ptr<class clang::ento::BugReport, struct std::default_delete<class clang::ento::BugReport>>))
>>> referenced by clangStaticAnalyzerCore.lib(ExplodedGraph.cpp.obj):(public: class clang::Stmt const * __cdecl clang::ento::ExplodedNode::getStmtForDiagnostics(void) const)
>>> referenced 8 more times

lld-link: error: undefined symbol: public: class clang::CFG * __cdecl clang::AnalysisDeclContext::getCFG(void)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::issueWarningsForRegisteredVarDecl(class clang::VarDecl *))
>>> referenced 48 more times

lld-link: error: undefined symbol: public: static class std::basic_string<char, struct std::char_traits<char>, class std::allocator<char>> __cdecl clang::AnalysisDeclContext::getFunctionName(class clang::Decl const *)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(private: unsigned int __cdecl `anonymous namespace'::AnalysisConsumer::getModeForDecl(class clang::Decl const *, unsigned int) const)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(private: static struct llvm::TimeTraceMetadata __cdecl llvm::function_ref<struct llvm::TimeTraceMetadata __cdecl(void)>::callback_fn<class `public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *)'::`1'::<lambda_1>>(__int64))
>>> referenced 4 more times

lld-link: error: undefined symbol: public: static void const * __cdecl clang::RelaxedLiveVariables::getTag(void)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerCore.lib(SymbolManager.cpp.obj):(public: bool __cdecl clang::ento::SymbolReaper::isLive(class clang::ento::VarRegion const *, bool) const)
>>> referenced by clangStaticAnalyzerCore.lib(SymbolManager.cpp.obj):(public: bool __cdecl clang::ento::SymbolReaper::isLive(class clang::Expr const *, class clang::StackFrame const *) const)
>>> referenced 2 more times

lld-link: error: undefined symbol: private: class std::unique_ptr<class clang::ManagedAnalysis, struct std::default_delete<class clang::ManagedAnalysis>> & __cdecl clang::AnalysisDeclContext::getAnalysisImpl(void const *)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(bool __cdecl areAllValuesNoReturn(class clang::VarDecl const *, class clang::CFGBlock const &, class clang::AnalysisDeclContext &))
>>> referenced by clangStaticAnalyzerCore.lib(SymbolManager.cpp.obj):(public: bool __cdecl clang::ento::SymbolReaper::isLive(class clang::ento::VarRegion const *, bool) const)
>>> referenced 11 more times

lld-link: error: undefined symbol: public: static class std::unique_ptr<class clang::LiveVariables, struct std::default_delete<class clang::LiveVariables>> __cdecl clang::LiveVariables::computeLiveness(class clang::AnalysisDeclContext &, bool)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))
>>> referenced by clangStaticAnalyzerCore.lib(SymbolManager.cpp.obj):(public: bool __cdecl clang::ento::SymbolReaper::isLive(class clang::ento::VarRegion const *, bool) const)
>>> referenced by clangStaticAnalyzerCore.lib(SymbolManager.cpp.obj):(public: bool __cdecl clang::ento::SymbolReaper::isLive(class clang::Expr const *, class clang::StackFrame const *) const)
>>> referenced 4 more times

lld-link: error: undefined symbol: public: class clang::StackFrame const * __cdecl clang::StackFrameManager::getStackFrame(class clang::AnalysisDeclContext *, class clang::StackFrame const *, void const *, class clang::Expr const *, class clang::CFGBlock const *, unsigned int, unsigned int)
>>> referenced by clangStaticAnalyzerFrontend.lib(AnalysisConsumer.cpp.obj):(public: void __cdecl `anonymous namespace'::AnalysisConsumer::HandleCode(class clang::Decl *, unsigned int, enum Decl::ento::ExprEngine::InliningModes, class llvm::DenseSet<class clang::Decl const *, struct llvm::DenseMapInfo<class clang::Decl const *, void>> *))

lld-link: error: undefined symbol: public: __cdecl clang::AnalysisDeclContext::AnalysisDeclContext(class clang::AnalysisDeclContextManager *, class clang::Decl const *)
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::issueWarningsForRegisteredVarDecl(class clang::VarDecl *))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::IssueWarnings(class clang::TranslationUnitDecl *))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::IssueWarningsForImplicitFunction(class clang::Decl const *))
>>> referenced 1 more times

lld-link: error: undefined symbol: public: void __cdecl clang::AnalysisDeclContext::registerForcedBlockExpression(class clang::Stmt const *)
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::issueWarningsForRegisteredVarDecl(class clang::VarDecl *))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::IssueWarnings(class clang::sema::AnalysisBasedWarnings::Policy, class clang::sema::FunctionScopeInfo *, class clang::Decl const *, class clang::QualType))

lld-link: error: undefined symbol: public: class clang::CFGReverseBlockReachabilityAnalysis * __cdecl clang::AnalysisDeclContext::getCFGReachablityAnalysis(void)
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::issueWarningsForRegisteredVarDecl(class clang::VarDecl *))
>>> referenced by clangSema.lib(AnalysisBasedWarnings.cpp.obj):(public: void __cdecl clang::sema::AnalysisBasedWarnings::IssueWarnings(class clang::sema::AnalysisBasedWarnings::Policy, class clang::sema::FunctionScopeInfo *, class clang::Decl const *, class clang::QualType))

lld-link: error: too many errors emitted, stopping now (use /errorlimit:0 to see all errors)
```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/207194