From f035b75d8f079a7b3c8d5c163e2ab0596ac59d17 Mon Sep 17 00:00:00 2001 From: Gabor Marton Date: Tue, 27 Aug 2019 11:36:10 +0000 Subject: [ASTImporter] Fix name conflict handling with different strategies There are numorous flaws about the name conflict handling, this patch attempts fixes them. Changes in details: * HandleNameConflict return with a false DeclarationName Hitherto we effectively never returned with a NameConflict error, even if the preceding StructuralMatch indicated a conflict. Because we just simply returned with the parameter `Name` in HandleNameConflict and that name is almost always `true` when converted to `bool`. * Add tests which indicate wrong NameConflict handling * Add to ConflictingDecls only if decl kind is different Note, we might not indicate an ODR error when there is an existing record decl and a enum is imported with same name. But there are other cases. E.g. think about the case when we import a FunctionTemplateDecl with name f and we found a simple FunctionDecl with name f. They overload. Or in case of a ClassTemplateDecl and CXXRecordDecl, the CXXRecordDecl could be the 'templated' class, so it would be false to report error. So I think we should report a name conflict error only when we are 100% sure of that. That is why I think it should be a general pattern to report the error only if the kind is the same. * Fix failing ctu test with EnumConstandDecl In ctu-main.c we have the enum class 'A' which brings in the enum constant 'x' with value 0 into the global namespace. In ctu-other.c we had the enum class 'B' which brought in the same name ('x') as an enum constant but with a different enum value (42). This is clearly an ODR violation in the global namespace. The solution was to rename the second enum constant. * Introduce ODR handling strategies Reviewers: a_sidorin, shafik Differential Revision: https://reviews.llvm.org/D59692 llvm-svn: 370045 --- clang/lib/AST/ASTImporter.cpp | 171 ++++++++++++++++++++++-------------------- 1 file changed, 90 insertions(+), 81 deletions(-) (limited to 'clang/lib') diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp index 8a442bbef66..19321fd0747 100644 --- a/clang/lib/AST/ASTImporter.cpp +++ b/clang/lib/AST/ASTImporter.cpp @@ -80,6 +80,7 @@ namespace clang { using ExpectedExpr = llvm::Expected; using ExpectedDecl = llvm::Expected; using ExpectedSLoc = llvm::Expected; + using ExpectedName = llvm::Expected; std::string ImportError::toString() const { // FIXME: Improve error texts. @@ -2247,11 +2248,13 @@ ExpectedDecl ASTNodeImporter::VisitNamespaceDecl(NamespaceDecl *D) { } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, Decl::IDNS_Namespace, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, Decl::IDNS_Namespace, ConflictingDecls.data(), + ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -2355,21 +2358,21 @@ ASTNodeImporter::VisitTypedefNameDecl(TypedefNameDecl *D, bool IsAlias) { // already have a complete underlying type then return with that. if (!FromUT->isIncompleteType() && !FoundUT->isIncompleteType()) return Importer.MapImported(D, FoundTypedef); + // FIXME Handle redecl chain. When you do that make consistent changes + // in ASTImporterLookupTable too. + } else { + ConflictingDecls.push_back(FoundDecl); } - // FIXME Handle redecl chain. When you do that make consistent changes - // in ASTImporterLookupTable too. - break; } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, IDNS, ConflictingDecls.data(), ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -2442,11 +2445,12 @@ ASTNodeImporter::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) { } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, IDNS, ConflictingDecls.data(), ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -2550,17 +2554,18 @@ ExpectedDecl ASTNodeImporter::VisitEnumDecl(EnumDecl *D) { continue; if (IsStructuralMatch(D, FoundEnum)) return Importer.MapImported(D, FoundEnum); + ConflictingDecls.push_back(FoundDecl); } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(SearchName, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + SearchName, DC, IDNS, ConflictingDecls.data(), + ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -2685,17 +2690,18 @@ ExpectedDecl ASTNodeImporter::VisitRecordDecl(RecordDecl *D) { PrevDecl = FoundRecord->getMostRecentDecl(); break; } - } - - ConflictingDecls.push_back(FoundDecl); + ConflictingDecls.push_back(FoundDecl); + } // kind is RecordDecl } // for if (!ConflictingDecls.empty() && SearchName) { - Name = Importer.HandleNameConflict(SearchName, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + SearchName, DC, IDNS, ConflictingDecls.data(), + ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -2854,17 +2860,17 @@ ExpectedDecl ASTNodeImporter::VisitEnumConstantDecl(EnumConstantDecl *D) { if (auto *FoundEnumConstant = dyn_cast(FoundDecl)) { if (IsStructuralMatch(D, FoundEnumConstant)) return Importer.MapImported(D, FoundEnumConstant); + ConflictingDecls.push_back(FoundDecl); } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, IDNS, ConflictingDecls.data(), ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -3102,17 +3108,17 @@ ExpectedDecl ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) { << Name << D->getType() << FoundFunction->getType(); Importer.ToDiag(FoundFunction->getLocation(), diag::note_odr_value_here) << FoundFunction->getType(); + ConflictingDecls.push_back(FoundDecl); } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, IDNS, ConflictingDecls.data(), ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -3758,17 +3764,17 @@ ExpectedDecl ASTNodeImporter::VisitVarDecl(VarDecl *D) { << Name << D->getType() << FoundVar->getType(); Importer.ToDiag(FoundVar->getLocation(), diag::note_odr_value_here) << FoundVar->getType(); + ConflictingDecls.push_back(FoundDecl); } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, IDNS, - ConflictingDecls.data(), - ConflictingDecls.size()); - if (!Name) - return make_error(ImportError::NameConflict); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, IDNS, ConflictingDecls.data(), ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } } @@ -5106,19 +5112,19 @@ ExpectedDecl ASTNodeImporter::VisitClassTemplateDecl(ClassTemplateDecl *D) { // see ASTTests test ImportExistingFriendClassTemplateDef. continue; } + ConflictingDecls.push_back(FoundDecl); } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, Decl::IDNS_Ordinary, - ConflictingDecls.data(), - ConflictingDecls.size()); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, Decl::IDNS_Ordinary, ConflictingDecls.data(), + ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } - - if (!Name) - return make_error(ImportError::NameConflict); } CXXRecordDecl *FromTemplated = D->getTemplatedDecl(); @@ -5391,22 +5397,20 @@ ExpectedDecl ASTNodeImporter::VisitVarTemplateDecl(VarTemplateDecl *D) { FoundTemplate->getTemplatedDecl()); return Importer.MapImported(D, FoundTemplate); } + ConflictingDecls.push_back(FoundDecl); } - - ConflictingDecls.push_back(FoundDecl); } if (!ConflictingDecls.empty()) { - Name = Importer.HandleNameConflict(Name, DC, Decl::IDNS_Ordinary, - ConflictingDecls.data(), - ConflictingDecls.size()); + ExpectedName NameOrErr = Importer.HandleNameConflict( + Name, DC, Decl::IDNS_Ordinary, ConflictingDecls.data(), + ConflictingDecls.size()); + if (NameOrErr) + Name = NameOrErr.get(); + else + return NameOrErr.takeError(); } - if (!Name) - // FIXME: Is it possible to get other error than name conflict? - // (Put this `if` into the previous `if`?) - return make_error(ImportError::NameConflict); - VarDecl *DTemplated = D->getTemplatedDecl(); // Import the type. @@ -7817,7 +7821,7 @@ ASTImporter::ASTImporter(ASTContext &ToContext, FileManager &ToFileManager, std::shared_ptr SharedState) : SharedState(SharedState), ToContext(ToContext), FromContext(FromContext), ToFileManager(ToFileManager), FromFileManager(FromFileManager), - Minimal(MinimalImport) { + Minimal(MinimalImport), ODRHandling(ODRHandlingType::Conservative) { // Create a default state without the lookup table: LLDB case. if (!SharedState) { @@ -8744,12 +8748,17 @@ Expected ASTImporter::Import(Selector FromSel) { return ToContext.Selectors.getSelector(FromSel.getNumArgs(), Idents.data()); } -DeclarationName ASTImporter::HandleNameConflict(DeclarationName Name, - DeclContext *DC, - unsigned IDNS, - NamedDecl **Decls, - unsigned NumDecls) { - return Name; +Expected ASTImporter::HandleNameConflict(DeclarationName Name, + DeclContext *DC, + unsigned IDNS, + NamedDecl **Decls, + unsigned NumDecls) { + if (ODRHandling == ODRHandlingType::Conservative) + // Report error at any name conflict. + return make_error(ImportError::NameConflict); + else + // Allow to create the new Decl with the same name. + return Name; } DiagnosticBuilder ASTImporter::ToDiag(SourceLocation Loc, unsigned DiagID) { -- cgit v1.2.3