Author: balazske Date: Mon Aug 12 03:07:38 2019 New Revision: 368551 URL: http://llvm.org/viewvc/llvm-project?rev=368551&view=rev Log: [ASTImporter] Fix for import of friend class template with definition.
Summary: If there is a friend class template "prototype" (forward declaration) and later a definition for it in the existing code, this existing definition may be not found by ASTImporter because it is not linked to the prototype (under the friend AST node). The problem is fixed by looping over all found matching decls instead of break after the first found one. Reviewers: martong, a.sidorin, shafik, a_sidorin Reviewed By: a_sidorin Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D65269 Modified: cfe/trunk/lib/AST/ASTImporter.cpp cfe/trunk/unittests/AST/ASTImporterTest.cpp Modified: cfe/trunk/lib/AST/ASTImporter.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ASTImporter.cpp?rev=368551&r1=368550&r2=368551&view=diff ============================================================================== --- cfe/trunk/lib/AST/ASTImporter.cpp (original) +++ cfe/trunk/lib/AST/ASTImporter.cpp Mon Aug 12 03:07:38 2019 @@ -5082,11 +5082,13 @@ ExpectedDecl ASTNodeImporter::VisitClass if (IsStructuralMatch(D, FoundTemplate)) { ClassTemplateDecl *TemplateWithDef = getTemplateDefinition(FoundTemplate); - if (D->isThisDeclarationADefinition() && TemplateWithDef) { + if (D->isThisDeclarationADefinition() && TemplateWithDef) return Importer.MapImported(D, TemplateWithDef); - } - FoundByLookup = FoundTemplate; - break; + if (!FoundByLookup) + FoundByLookup = FoundTemplate; + // Search in all matches because there may be multiple decl chains, + // see ASTTests test ImportExistingFriendClassTemplateDef. + continue; } } Modified: cfe/trunk/unittests/AST/ASTImporterTest.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/unittests/AST/ASTImporterTest.cpp?rev=368551&r1=368550&r2=368551&view=diff ============================================================================== --- cfe/trunk/unittests/AST/ASTImporterTest.cpp (original) +++ cfe/trunk/unittests/AST/ASTImporterTest.cpp Mon Aug 12 03:07:38 2019 @@ -5191,6 +5191,50 @@ TEST_P(ASTImporterOptionSpecificTestBase EXPECT_TRUE(ToF); } +TEST_P(ASTImporterOptionSpecificTestBase, + ImportExistingFriendClassTemplateDef) { + auto Code = + R"( + template <class T1, class T2> + struct Base { + template <class U1, class U2> + friend struct Class; + }; + template <class T1, class T2> + struct Class { }; + )"; + + TranslationUnitDecl *ToTU = getToTuDecl(Code, Lang_CXX); + TranslationUnitDecl *FromTU = getTuDecl(Code, Lang_CXX, "input.cc"); + + auto *ToClassProto = FirstDeclMatcher<ClassTemplateDecl>().match( + ToTU, classTemplateDecl(hasName("Class"))); + auto *ToClassDef = LastDeclMatcher<ClassTemplateDecl>().match( + ToTU, classTemplateDecl(hasName("Class"))); + ASSERT_FALSE(ToClassProto->isThisDeclarationADefinition()); + ASSERT_TRUE(ToClassDef->isThisDeclarationADefinition()); + // Previous friend decl is not linked to it! + ASSERT_FALSE(ToClassDef->getPreviousDecl()); + ASSERT_EQ(ToClassDef->getMostRecentDecl(), ToClassDef); + ASSERT_EQ(ToClassProto->getMostRecentDecl(), ToClassProto); + + auto *FromClassProto = FirstDeclMatcher<ClassTemplateDecl>().match( + FromTU, classTemplateDecl(hasName("Class"))); + auto *FromClassDef = LastDeclMatcher<ClassTemplateDecl>().match( + FromTU, classTemplateDecl(hasName("Class"))); + ASSERT_FALSE(FromClassProto->isThisDeclarationADefinition()); + ASSERT_TRUE(FromClassDef->isThisDeclarationADefinition()); + ASSERT_FALSE(FromClassDef->getPreviousDecl()); + ASSERT_EQ(FromClassDef->getMostRecentDecl(), FromClassDef); + ASSERT_EQ(FromClassProto->getMostRecentDecl(), FromClassProto); + + auto *ImportedDef = Import(FromClassDef, Lang_CXX); + // At import we should find the definition for 'Class' even if the + // prototype (inside 'friend') for it comes first in the AST and is not + // linked to the definition. + EXPECT_EQ(ImportedDef, ToClassDef); +} + struct LLDBLookupTest : ASTImporterOptionSpecificTestBase { LLDBLookupTest() { Creator = [](ASTContext &ToContext, FileManager &ToFileManager, _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
