| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "FindBadConstructsConsumer.h" |
| |
| #include "clang/Frontend/CompilerInstance.h" |
| #include "clang/AST/Attr.h" |
| #include "clang/Lex/Lexer.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace clang; |
| |
| namespace chrome_checker { |
| |
| namespace { |
| |
| const char kMethodRequiresOverride[] = |
| "[chromium-style] Overriding method must be marked with 'override' or " |
| "'final'."; |
| const char kRedundantVirtualSpecifier[] = |
| "[chromium-style] %0 is redundant; %1 implies %0."; |
| // http://llvm.org/bugs/show_bug.cgi?id=21051 has been filed to make this a |
| // Clang warning. |
| const char kBaseMethodVirtualAndFinal[] = |
| "[chromium-style] The virtual method does not override anything and is " |
| "final; consider making it non-virtual."; |
| const char kNoExplicitDtor[] = |
| "[chromium-style] Classes that are ref-counted should have explicit " |
| "destructors that are declared protected or private."; |
| const char kPublicDtor[] = |
| "[chromium-style] Classes that are ref-counted should have " |
| "destructors that are declared protected or private."; |
| const char kProtectedNonVirtualDtor[] = |
| "[chromium-style] Classes that are ref-counted and have non-private " |
| "destructors should declare their destructor virtual."; |
| const char kWeakPtrFactoryOrder[] = |
| "[chromium-style] WeakPtrFactory members which refer to their outer class " |
| "must be the last member in the outer class definition."; |
| const char kBadLastEnumValue[] = |
| "[chromium-style] _LAST/Last constants of enum types must have the maximal " |
| "value for any constant of that type."; |
| const char kNoteInheritance[] = "[chromium-style] %0 inherits from %1 here"; |
| const char kNoteImplicitDtor[] = |
| "[chromium-style] No explicit destructor for %0 defined"; |
| const char kNotePublicDtor[] = |
| "[chromium-style] Public destructor declared here"; |
| const char kNoteProtectedNonVirtualDtor[] = |
| "[chromium-style] Protected non-virtual destructor declared here"; |
| |
| bool TypeHasNonTrivialDtor(const Type* type) { |
| if (const CXXRecordDecl* cxx_r = type->getPointeeCXXRecordDecl()) |
| return !cxx_r->hasTrivialDestructor(); |
| |
| return false; |
| } |
| |
| // Returns the underlying Type for |type| by expanding typedefs and removing |
| // any namespace qualifiers. This is similar to desugaring, except that for |
| // ElaboratedTypes, desugar will unwrap too much. |
| const Type* UnwrapType(const Type* type) { |
| if (const ElaboratedType* elaborated = dyn_cast<ElaboratedType>(type)) |
| return UnwrapType(elaborated->getNamedType().getTypePtr()); |
| if (const TypedefType* typedefed = dyn_cast<TypedefType>(type)) |
| return UnwrapType(typedefed->desugar().getTypePtr()); |
| return type; |
| } |
| |
| bool IsGtestTestFixture(const CXXRecordDecl* decl) { |
| return decl->getQualifiedNameAsString() == "testing::Test"; |
| } |
| |
| // Generates a fixit hint to remove the 'virtual' keyword. |
| // Unfortunately, there doesn't seem to be a good way to determine the source |
| // location of the 'virtual' keyword. It's available in Declarator, but that |
| // isn't accessible from the AST. So instead, make an educated guess that the |
| // first token is probably the virtual keyword. Strictly speaking, this doesn't |
| // have to be true, but it probably will be. |
| // TODO(dcheng): Add a warning to force virtual to always appear first ;-) |
| FixItHint FixItRemovalForVirtual(const SourceManager& manager, |
| const LangOptions& lang_opts, |
| const CXXMethodDecl* method) { |
| SourceRange range(method->getLocStart()); |
| // Get the spelling loc just in case it was expanded from a macro. |
| SourceRange spelling_range(manager.getSpellingLoc(range.getBegin())); |
| // Sanity check that the text looks like virtual. |
| StringRef text = clang::Lexer::getSourceText( |
| CharSourceRange::getTokenRange(spelling_range), manager, lang_opts); |
| if (text.trim() != "virtual") |
| return FixItHint(); |
| return FixItHint::CreateRemoval(range); |
| } |
| |
| bool IsPodOrTemplateType(const CXXRecordDecl& record) { |
| return record.isPOD() || |
| record.getDescribedClassTemplate() || |
| record.getTemplateSpecializationKind() || |
| record.isDependentType(); |
| } |
| |
| } // namespace |
| |
| FindBadConstructsConsumer::FindBadConstructsConsumer(CompilerInstance& instance, |
| const Options& options) |
| : ChromeClassTester(instance, options) { |
| // Messages for virtual method specifiers. |
| diag_method_requires_override_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kMethodRequiresOverride); |
| diag_redundant_virtual_specifier_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kRedundantVirtualSpecifier); |
| diag_base_method_virtual_and_final_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kBaseMethodVirtualAndFinal); |
| |
| // Messages for destructors. |
| diag_no_explicit_dtor_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kNoExplicitDtor); |
| diag_public_dtor_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kPublicDtor); |
| diag_protected_non_virtual_dtor_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kProtectedNonVirtualDtor); |
| |
| // Miscellaneous messages. |
| diag_weak_ptr_factory_order_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kWeakPtrFactoryOrder); |
| diag_bad_enum_last_value_ = |
| diagnostic().getCustomDiagID(getErrorLevel(), kBadLastEnumValue); |
| |
| // Registers notes to make it easier to interpret warnings. |
| diag_note_inheritance_ = |
| diagnostic().getCustomDiagID(DiagnosticsEngine::Note, kNoteInheritance); |
| diag_note_implicit_dtor_ = |
| diagnostic().getCustomDiagID(DiagnosticsEngine::Note, kNoteImplicitDtor); |
| diag_note_public_dtor_ = |
| diagnostic().getCustomDiagID(DiagnosticsEngine::Note, kNotePublicDtor); |
| diag_note_protected_non_virtual_dtor_ = diagnostic().getCustomDiagID( |
| DiagnosticsEngine::Note, kNoteProtectedNonVirtualDtor); |
| } |
| |
| bool FindBadConstructsConsumer::VisitDecl(clang::Decl* decl) { |
| clang::TagDecl* tag_decl = dyn_cast<clang::TagDecl>(decl); |
| if (tag_decl && tag_decl->isCompleteDefinition()) |
| CheckTag(tag_decl); |
| return true; |
| } |
| |
| void FindBadConstructsConsumer::CheckChromeClass(SourceLocation record_location, |
| CXXRecordDecl* record) { |
| // By default, the clang checker doesn't check some types (templates, etc). |
| // That was only a mistake; once Chromium code passes these checks, we should |
| // remove the "check-templates" option and remove this code. |
| // See crbug.com/441916 |
| if (!options_.check_templates && IsPodOrTemplateType(*record)) |
| return; |
| |
| bool implementation_file = InImplementationFile(record_location); |
| |
| if (!implementation_file) { |
| // Only check for "heavy" constructors/destructors in header files; |
| // within implementation files, there is no performance cost. |
| |
| // If this is a POD or a class template or a type dependent on a |
| // templated class, assume there's no ctor/dtor/virtual method |
| // optimization that we should do. |
| if (!IsPodOrTemplateType(*record)) |
| CheckCtorDtorWeight(record_location, record); |
| } |
| |
| bool warn_on_inline_bodies = !implementation_file; |
| // Check that all virtual methods are annotated with override or final. |
| // Note this could also apply to templates, but for some reason Clang |
| // does not always see the "override", so we get false positives. |
| // See http://llvm.org/bugs/show_bug.cgi?id=18440 and |
| // http://llvm.org/bugs/show_bug.cgi?id=21942 |
| if (!IsPodOrTemplateType(*record)) |
| CheckVirtualMethods(record_location, record, warn_on_inline_bodies); |
| |
| CheckRefCountedDtors(record_location, record); |
| |
| CheckWeakPtrFactoryMembers(record_location, record); |
| } |
| |
| void FindBadConstructsConsumer::CheckChromeEnum(SourceLocation enum_location, |
| EnumDecl* enum_decl) { |
| if (!options_.check_enum_last_value) |
| return; |
| |
| bool got_one = false; |
| bool is_signed = false; |
| llvm::APSInt max_so_far; |
| EnumDecl::enumerator_iterator iter; |
| for (iter = enum_decl->enumerator_begin(); |
| iter != enum_decl->enumerator_end(); |
| ++iter) { |
| llvm::APSInt current_value = iter->getInitVal(); |
| if (!got_one) { |
| max_so_far = current_value; |
| is_signed = current_value.isSigned(); |
| got_one = true; |
| } else { |
| if (is_signed != current_value.isSigned()) { |
| // This only happens in some cases when compiling C (not C++) files, |
| // so it is OK to bail out here. |
| return; |
| } |
| if (current_value > max_so_far) |
| max_so_far = current_value; |
| } |
| } |
| for (iter = enum_decl->enumerator_begin(); |
| iter != enum_decl->enumerator_end(); |
| ++iter) { |
| std::string name = iter->getNameAsString(); |
| if (((name.size() > 4 && name.compare(name.size() - 4, 4, "Last") == 0) || |
| (name.size() > 5 && name.compare(name.size() - 5, 5, "_LAST") == 0)) && |
| iter->getInitVal() < max_so_far) { |
| diagnostic().Report(iter->getLocation(), diag_bad_enum_last_value_); |
| } |
| } |
| } |
| |
| void FindBadConstructsConsumer::CheckCtorDtorWeight( |
| SourceLocation record_location, |
| CXXRecordDecl* record) { |
| // We don't handle anonymous structs. If this record doesn't have a |
| // name, it's of the form: |
| // |
| // struct { |
| // ... |
| // } name_; |
| if (record->getIdentifier() == NULL) |
| return; |
| |
| // Count the number of templated base classes as a feature of whether the |
| // destructor can be inlined. |
| int templated_base_classes = 0; |
| for (CXXRecordDecl::base_class_const_iterator it = record->bases_begin(); |
| it != record->bases_end(); |
| ++it) { |
| if (it->getTypeSourceInfo()->getTypeLoc().getTypeLocClass() == |
| TypeLoc::TemplateSpecialization) { |
| ++templated_base_classes; |
| } |
| } |
| |
| // Count the number of trivial and non-trivial member variables. |
| int trivial_member = 0; |
| int non_trivial_member = 0; |
| int templated_non_trivial_member = 0; |
| for (RecordDecl::field_iterator it = record->field_begin(); |
| it != record->field_end(); |
| ++it) { |
| CountType(it->getType().getTypePtr(), |
| &trivial_member, |
| &non_trivial_member, |
| &templated_non_trivial_member); |
| } |
| |
| // Check to see if we need to ban inlined/synthesized constructors. Note |
| // that the cutoffs here are kind of arbitrary. Scores over 10 break. |
| int dtor_score = 0; |
| // Deriving from a templated base class shouldn't be enough to trigger |
| // the ctor warning, but if you do *anything* else, it should. |
| // |
| // TODO(erg): This is motivated by templated base classes that don't have |
| // any data members. Somehow detect when templated base classes have data |
| // members and treat them differently. |
| dtor_score += templated_base_classes * 9; |
| // Instantiating a template is an insta-hit. |
| dtor_score += templated_non_trivial_member * 10; |
| // The fourth normal class member should trigger the warning. |
| dtor_score += non_trivial_member * 3; |
| |
| int ctor_score = dtor_score; |
| // You should be able to have 9 ints before we warn you. |
| ctor_score += trivial_member; |
| |
| if (ctor_score >= 10) { |
| if (!record->hasUserDeclaredConstructor()) { |
| emitWarning(record_location, |
| "Complex class/struct needs an explicit out-of-line " |
| "constructor."); |
| } else { |
| // Iterate across all the constructors in this file and yell if we |
| // find one that tries to be inline. |
| for (CXXRecordDecl::ctor_iterator it = record->ctor_begin(); |
| it != record->ctor_end(); |
| ++it) { |
| // The current check is buggy. An implicit copy constructor does not |
| // have an inline body, so this check never fires for classes with a |
| // user-declared out-of-line constructor. |
| if (it->hasInlineBody()) { |
| if (it->isCopyConstructor() && |
| !record->hasUserDeclaredCopyConstructor()) { |
| // In general, implicit constructors are generated on demand. But |
| // in the Windows component build, dllexport causes instantiation of |
| // the copy constructor which means that this fires on many more |
| // classes. For now, suppress this on dllexported classes. |
| // (This does mean that windows component builds will not emit this |
| // warning in some cases where it is emitted in other configs, but |
| // that's the better tradeoff at this point). |
| // TODO(dcheng): With the RecursiveASTVisitor, these warnings might |
| // be emitted on other platforms too, reevaluate if we want to keep |
| // surpressing this then http://crbug.com/467288 |
| if (!record->hasAttr<DLLExportAttr>()) |
| emitWarning(record_location, |
| "Complex class/struct needs an explicit out-of-line " |
| "copy constructor."); |
| } else { |
| // See the comment in the previous branch about copy constructors. |
| // This does the same for implicit move constructors. |
| bool is_likely_compiler_generated_dllexport_move_ctor = |
| it->isMoveConstructor() && |
| !record->hasUserDeclaredMoveConstructor() && |
| record->hasAttr<DLLExportAttr>(); |
| if (!is_likely_compiler_generated_dllexport_move_ctor) |
| emitWarning(it->getInnerLocStart(), |
| "Complex constructor has an inlined body."); |
| } |
| } else if (it->isInlined() && !it->isInlineSpecified() && |
| !it->isDeleted() && (!it->isCopyOrMoveConstructor() || |
| it->isExplicitlyDefaulted())) { |
| // isInlined() is a more reliable check than hasInlineBody(), but |
| // unfortunately, it results in warnings for implicit copy/move |
| // constructors in the previously mentioned situation. To preserve |
| // compatibility with existing Chromium code, only warn if it's an |
| // explicitly defaulted copy or move constructor. |
| emitWarning(it->getInnerLocStart(), |
| "Complex constructor has an inlined body."); |
| } |
| } |
| } |
| } |
| |
| // The destructor side is equivalent except that we don't check for |
| // trivial members; 20 ints don't need a destructor. |
| if (dtor_score >= 10 && !record->hasTrivialDestructor()) { |
| if (!record->hasUserDeclaredDestructor()) { |
| emitWarning(record_location, |
| "Complex class/struct needs an explicit out-of-line " |
| "destructor."); |
| } else if (CXXDestructorDecl* dtor = record->getDestructor()) { |
| if (dtor->isInlined() && !dtor->isInlineSpecified() && |
| !dtor->isDeleted()) { |
| emitWarning(dtor->getInnerLocStart(), |
| "Complex destructor has an inline body."); |
| } |
| } |
| } |
| } |
| |
| bool FindBadConstructsConsumer::InTestingNamespace(const Decl* record) { |
| return GetNamespace(record).find("testing") != std::string::npos; |
| } |
| |
| bool FindBadConstructsConsumer::IsMethodInBannedOrTestingNamespace( |
| const CXXMethodDecl* method) { |
| if (InBannedNamespace(method)) |
| return true; |
| for (CXXMethodDecl::method_iterator i = method->begin_overridden_methods(); |
| i != method->end_overridden_methods(); |
| ++i) { |
| const CXXMethodDecl* overridden = *i; |
| if (IsMethodInBannedOrTestingNamespace(overridden) || |
| // Provide an exception for ::testing::Test. gtest itself uses some |
| // magic to try to make sure SetUp()/TearDown() aren't capitalized |
| // incorrectly, but having the plugin enforce override is also nice. |
| (InTestingNamespace(overridden) && |
| !IsGtestTestFixture(overridden->getParent()))) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| SuppressibleDiagnosticBuilder |
| FindBadConstructsConsumer::ReportIfSpellingLocNotIgnored( |
| SourceLocation loc, |
| unsigned diagnostic_id) { |
| return SuppressibleDiagnosticBuilder( |
| &diagnostic(), loc, diagnostic_id, |
| InBannedDirectory(instance().getSourceManager().getSpellingLoc(loc))); |
| } |
| |
| // Checks that virtual methods are correctly annotated, and have no body in a |
| // header file. |
| void FindBadConstructsConsumer::CheckVirtualMethods( |
| SourceLocation record_location, |
| CXXRecordDecl* record, |
| bool warn_on_inline_bodies) { |
| // Gmock objects trigger these for each MOCK_BLAH() macro used. So we have a |
| // trick to get around that. If a class has member variables whose types are |
| // in the "testing" namespace (which is how gmock works behind the scenes), |
| // there's a really high chance we won't care about these errors |
| for (CXXRecordDecl::field_iterator it = record->field_begin(); |
| it != record->field_end(); |
| ++it) { |
| CXXRecordDecl* record_type = it->getTypeSourceInfo() |
| ->getTypeLoc() |
| .getTypePtr() |
| ->getAsCXXRecordDecl(); |
| if (record_type) { |
| if (InTestingNamespace(record_type)) { |
| return; |
| } |
| } |
| } |
| |
| for (CXXRecordDecl::method_iterator it = record->method_begin(); |
| it != record->method_end(); |
| ++it) { |
| if (it->isCopyAssignmentOperator() || isa<CXXConstructorDecl>(*it)) { |
| // Ignore constructors and assignment operators. |
| } else if (isa<CXXDestructorDecl>(*it) && |
| !record->hasUserDeclaredDestructor()) { |
| // Ignore non-user-declared destructors. |
| } else if (!it->isVirtual()) { |
| continue; |
| } else { |
| CheckVirtualSpecifiers(*it); |
| if (warn_on_inline_bodies) |
| CheckVirtualBodies(*it); |
| } |
| } |
| } |
| |
| // Makes sure that virtual methods use the most appropriate specifier. If a |
| // virtual method overrides a method from a base class, only the override |
| // specifier should be used. If the method should not be overridden by derived |
| // classes, only the final specifier should be used. |
| void FindBadConstructsConsumer::CheckVirtualSpecifiers( |
| const CXXMethodDecl* method) { |
| bool is_override = method->size_overridden_methods() > 0; |
| bool has_virtual = method->isVirtualAsWritten(); |
| OverrideAttr* override_attr = method->getAttr<OverrideAttr>(); |
| FinalAttr* final_attr = method->getAttr<FinalAttr>(); |
| |
| if (IsMethodInBannedOrTestingNamespace(method)) |
| return; |
| |
| SourceManager& manager = instance().getSourceManager(); |
| const LangOptions& lang_opts = instance().getLangOpts(); |
| |
| // Complain if a method is annotated virtual && (override || final). |
| if (has_virtual && (override_attr || final_attr)) { |
| // ... but only if virtual does not originate in a macro from a banned file. |
| // Note this is just an educated guess: the assumption here is that any |
| // macro for declaring methods will probably be at the start of the method's |
| // source range. |
| ReportIfSpellingLocNotIgnored(method->getLocStart(), |
| diag_redundant_virtual_specifier_) |
| << "'virtual'" |
| << (override_attr ? static_cast<Attr*>(override_attr) : final_attr) |
| << FixItRemovalForVirtual(manager, lang_opts, method); |
| } |
| |
| // Complain if a method is an override and is not annotated with override or |
| // final. |
| if (is_override && !override_attr && !final_attr) { |
| SourceRange range = method->getSourceRange(); |
| SourceLocation loc; |
| if (method->hasInlineBody()) { |
| loc = method->getBody()->getSourceRange().getBegin(); |
| } else { |
| loc = Lexer::getLocForEndOfToken(manager.getSpellingLoc(range.getEnd()), |
| 0, manager, lang_opts); |
| // The original code used the ending source loc of TypeSourceInfo's |
| // TypeLoc. Unfortunately, this breaks down in the presence of attributes. |
| // Attributes often appear at the end of a TypeLoc, e.g. |
| // virtual ULONG __stdcall AddRef() |
| // has a TypeSourceInfo that looks something like: |
| // ULONG AddRef() __attribute(stdcall) |
| // so a fix-it insertion would be generated to insert 'override' after |
| // __stdcall in the code as written. |
| // While using the spelling loc of the CXXMethodDecl fixes attribute |
| // handling, it breaks handling of "= 0" and similar constructs.. To work |
| // around this, scan backwards in the source text for a '=' or ')' token |
| // and adjust the location as needed... |
| for (SourceLocation l = loc.getLocWithOffset(-1); |
| l != manager.getLocForStartOfFile(manager.getFileID(loc)); |
| l = l.getLocWithOffset(-1)) { |
| l = Lexer::GetBeginningOfToken(l, manager, lang_opts); |
| Token token; |
| // getRawToken() returns *true* on failure. In that case, just give up |
| // and don't bother generating a possibly incorrect fix-it. |
| if (Lexer::getRawToken(l, token, manager, lang_opts, true)) { |
| loc = SourceLocation(); |
| break; |
| } |
| if (token.is(tok::r_paren)) { |
| break; |
| } else if (token.is(tok::equal)) { |
| loc = l; |
| break; |
| } |
| } |
| } |
| // Again, only emit the warning if it doesn't originate from a macro in |
| // a system header. |
| if (loc.isValid()) { |
| ReportIfSpellingLocNotIgnored(loc, diag_method_requires_override_) |
| << FixItHint::CreateInsertion(loc, " override"); |
| } else { |
| ReportIfSpellingLocNotIgnored(range.getBegin(), |
| diag_method_requires_override_); |
| } |
| } |
| |
| if (final_attr && override_attr) { |
| ReportIfSpellingLocNotIgnored(override_attr->getLocation(), |
| diag_redundant_virtual_specifier_) |
| << override_attr << final_attr |
| << FixItHint::CreateRemoval(override_attr->getRange()); |
| } |
| |
| if (final_attr && !is_override) { |
| ReportIfSpellingLocNotIgnored(method->getLocStart(), |
| diag_base_method_virtual_and_final_) |
| << FixItRemovalForVirtual(manager, lang_opts, method) |
| << FixItHint::CreateRemoval(final_attr->getRange()); |
| } |
| } |
| |
| void FindBadConstructsConsumer::CheckVirtualBodies( |
| const CXXMethodDecl* method) { |
| // Virtual methods should not have inline definitions beyond "{}". This |
| // only matters for header files. |
| if (method->hasBody() && method->hasInlineBody()) { |
| if (CompoundStmt* cs = dyn_cast<CompoundStmt>(method->getBody())) { |
| if (cs->size()) { |
| SourceLocation loc = cs->getLBracLoc(); |
| // CR_BEGIN_MSG_MAP_EX and BEGIN_SAFE_MSG_MAP_EX try to be compatible |
| // to BEGIN_MSG_MAP(_EX). So even though they are in chrome code, |
| // we can't easily fix them, so explicitly whitelist them here. |
| bool emit = true; |
| if (loc.isMacroID()) { |
| SourceManager& manager = instance().getSourceManager(); |
| if (InBannedDirectory(manager.getSpellingLoc(loc))) |
| emit = false; |
| else { |
| StringRef name = Lexer::getImmediateMacroName( |
| loc, manager, instance().getLangOpts()); |
| if (name == "CR_BEGIN_MSG_MAP_EX" || |
| name == "BEGIN_SAFE_MSG_MAP_EX") |
| emit = false; |
| } |
| } |
| if (emit) |
| emitWarning(loc, |
| "virtual methods with non-empty bodies shouldn't be " |
| "declared inline."); |
| } |
| } |
| } |
| } |
| |
| void FindBadConstructsConsumer::CountType(const Type* type, |
| int* trivial_member, |
| int* non_trivial_member, |
| int* templated_non_trivial_member) { |
| switch (type->getTypeClass()) { |
| case Type::Record: { |
| // Simplifying; the whole class isn't trivial if the dtor is, but |
| // we use this as a signal about complexity. |
| if (TypeHasNonTrivialDtor(type)) |
| (*trivial_member)++; |
| else |
| (*non_trivial_member)++; |
| break; |
| } |
| case Type::TemplateSpecialization: { |
| TemplateName name = |
| dyn_cast<TemplateSpecializationType>(type)->getTemplateName(); |
| bool whitelisted_template = false; |
| |
| // HACK: I'm at a loss about how to get the syntax checker to get |
| // whether a template is externed or not. For the first pass here, |
| // just do retarded string comparisons. |
| if (TemplateDecl* decl = name.getAsTemplateDecl()) { |
| std::string base_name = decl->getNameAsString(); |
| if (base_name == "basic_string") |
| whitelisted_template = true; |
| } |
| |
| if (whitelisted_template) |
| (*non_trivial_member)++; |
| else |
| (*templated_non_trivial_member)++; |
| break; |
| } |
| case Type::Elaborated: { |
| CountType(dyn_cast<ElaboratedType>(type)->getNamedType().getTypePtr(), |
| trivial_member, |
| non_trivial_member, |
| templated_non_trivial_member); |
| break; |
| } |
| case Type::Typedef: { |
| while (const TypedefType* TT = dyn_cast<TypedefType>(type)) { |
| type = TT->getDecl()->getUnderlyingType().getTypePtr(); |
| } |
| CountType(type, |
| trivial_member, |
| non_trivial_member, |
| templated_non_trivial_member); |
| break; |
| } |
| default: { |
| // Stupid assumption: anything we see that isn't the above is one of |
| // the 20 integer types. |
| (*trivial_member)++; |
| break; |
| } |
| } |
| } |
| |
| // Check |record| for issues that are problematic for ref-counted types. |
| // Note that |record| may not be a ref-counted type, but a base class for |
| // a type that is. |
| // If there are issues, update |loc| with the SourceLocation of the issue |
| // and returns appropriately, or returns None if there are no issues. |
| FindBadConstructsConsumer::RefcountIssue |
| FindBadConstructsConsumer::CheckRecordForRefcountIssue( |
| const CXXRecordDecl* record, |
| SourceLocation& loc) { |
| if (!record->hasUserDeclaredDestructor()) { |
| loc = record->getLocation(); |
| return ImplicitDestructor; |
| } |
| |
| if (CXXDestructorDecl* dtor = record->getDestructor()) { |
| if (dtor->getAccess() == AS_public) { |
| loc = dtor->getInnerLocStart(); |
| return PublicDestructor; |
| } |
| } |
| |
| return None; |
| } |
| |
| // Returns true if |base| specifies one of the Chromium reference counted |
| // classes (base::RefCounted / base::RefCountedThreadSafe). |
| bool FindBadConstructsConsumer::IsRefCountedCallback( |
| const CXXBaseSpecifier* base, |
| CXXBasePath& path, |
| void* user_data) { |
| FindBadConstructsConsumer* self = |
| static_cast<FindBadConstructsConsumer*>(user_data); |
| |
| const TemplateSpecializationType* base_type = |
| dyn_cast<TemplateSpecializationType>( |
| UnwrapType(base->getType().getTypePtr())); |
| if (!base_type) { |
| // Base-most definition is not a template, so this cannot derive from |
| // base::RefCounted. However, it may still be possible to use with a |
| // scoped_refptr<> and support ref-counting, so this is not a perfect |
| // guarantee of safety. |
| return false; |
| } |
| |
| TemplateName name = base_type->getTemplateName(); |
| if (TemplateDecl* decl = name.getAsTemplateDecl()) { |
| std::string base_name = decl->getNameAsString(); |
| |
| // Check for both base::RefCounted and base::RefCountedThreadSafe. |
| if (base_name.compare(0, 10, "RefCounted") == 0 && |
| self->GetNamespace(decl) == "base") { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| // Returns true if |base| specifies a class that has a public destructor, |
| // either explicitly or implicitly. |
| bool FindBadConstructsConsumer::HasPublicDtorCallback( |
| const CXXBaseSpecifier* base, |
| CXXBasePath& path, |
| void* user_data) { |
| // Only examine paths that have public inheritance, as they are the |
| // only ones which will result in the destructor potentially being |
| // exposed. This check is largely redundant, as Chromium code should be |
| // exclusively using public inheritance. |
| if (path.Access != AS_public) |
| return false; |
| |
| CXXRecordDecl* record = |
| dyn_cast<CXXRecordDecl>(base->getType()->getAs<RecordType>()->getDecl()); |
| SourceLocation unused; |
| return None != CheckRecordForRefcountIssue(record, unused); |
| } |
| |
| // Outputs a C++ inheritance chain as a diagnostic aid. |
| void FindBadConstructsConsumer::PrintInheritanceChain(const CXXBasePath& path) { |
| for (CXXBasePath::const_iterator it = path.begin(); it != path.end(); ++it) { |
| diagnostic().Report(it->Base->getLocStart(), diag_note_inheritance_) |
| << it->Class << it->Base->getType(); |
| } |
| } |
| |
| unsigned FindBadConstructsConsumer::DiagnosticForIssue(RefcountIssue issue) { |
| switch (issue) { |
| case ImplicitDestructor: |
| return diag_no_explicit_dtor_; |
| case PublicDestructor: |
| return diag_public_dtor_; |
| case None: |
| assert(false && "Do not call DiagnosticForIssue with issue None"); |
| return 0; |
| } |
| assert(false); |
| return 0; |
| } |
| |
| // Check |record| to determine if it has any problematic refcounting |
| // issues and, if so, print them as warnings/errors based on the current |
| // value of getErrorLevel(). |
| // |
| // If |record| is a C++ class, and if it inherits from one of the Chromium |
| // ref-counting classes (base::RefCounted / base::RefCountedThreadSafe), |
| // ensure that there are no public destructors in the class hierarchy. This |
| // is to guard against accidentally stack-allocating a RefCounted class or |
| // sticking it in a non-ref-counted container (like scoped_ptr<>). |
| void FindBadConstructsConsumer::CheckRefCountedDtors( |
| SourceLocation record_location, |
| CXXRecordDecl* record) { |
| // Skip anonymous structs. |
| if (record->getIdentifier() == NULL) |
| return; |
| |
| // Determine if the current type is even ref-counted. |
| CXXBasePaths refcounted_path; |
| if (!record->lookupInBases(&FindBadConstructsConsumer::IsRefCountedCallback, |
| this, |
| refcounted_path)) { |
| return; // Class does not derive from a ref-counted base class. |
| } |
| |
| // Easy check: Check to see if the current type is problematic. |
| SourceLocation loc; |
| RefcountIssue issue = CheckRecordForRefcountIssue(record, loc); |
| if (issue != None) { |
| diagnostic().Report(loc, DiagnosticForIssue(issue)); |
| PrintInheritanceChain(refcounted_path.front()); |
| return; |
| } |
| if (CXXDestructorDecl* dtor = |
| refcounted_path.begin()->back().Class->getDestructor()) { |
| if (dtor->getAccess() == AS_protected && !dtor->isVirtual()) { |
| loc = dtor->getInnerLocStart(); |
| diagnostic().Report(loc, diag_protected_non_virtual_dtor_); |
| return; |
| } |
| } |
| |
| // Long check: Check all possible base classes for problematic |
| // destructors. This checks for situations involving multiple |
| // inheritance, where the ref-counted class may be implementing an |
| // interface that has a public or implicit destructor. |
| // |
| // struct SomeInterface { |
| // virtual void DoFoo(); |
| // }; |
| // |
| // struct RefCountedInterface |
| // : public base::RefCounted<RefCountedInterface>, |
| // public SomeInterface { |
| // private: |
| // friend class base::Refcounted<RefCountedInterface>; |
| // virtual ~RefCountedInterface() {} |
| // }; |
| // |
| // While RefCountedInterface is "safe", in that its destructor is |
| // private, it's possible to do the following "unsafe" code: |
| // scoped_refptr<RefCountedInterface> some_class( |
| // new RefCountedInterface); |
| // // Calls SomeInterface::~SomeInterface(), which is unsafe. |
| // delete static_cast<SomeInterface*>(some_class.get()); |
| if (!options_.check_base_classes) |
| return; |
| |
| // Find all public destructors. This will record the class hierarchy |
| // that leads to the public destructor in |dtor_paths|. |
| CXXBasePaths dtor_paths; |
| if (!record->lookupInBases(&FindBadConstructsConsumer::HasPublicDtorCallback, |
| this, |
| dtor_paths)) { |
| return; |
| } |
| |
| for (CXXBasePaths::const_paths_iterator it = dtor_paths.begin(); |
| it != dtor_paths.end(); |
| ++it) { |
| // The record with the problem will always be the last record |
| // in the path, since it is the record that stopped the search. |
| const CXXRecordDecl* problem_record = dyn_cast<CXXRecordDecl>( |
| it->back().Base->getType()->getAs<RecordType>()->getDecl()); |
| |
| issue = CheckRecordForRefcountIssue(problem_record, loc); |
| |
| if (issue == ImplicitDestructor) { |
| diagnostic().Report(record_location, diag_no_explicit_dtor_); |
| PrintInheritanceChain(refcounted_path.front()); |
| diagnostic().Report(loc, diag_note_implicit_dtor_) << problem_record; |
| PrintInheritanceChain(*it); |
| } else if (issue == PublicDestructor) { |
| diagnostic().Report(record_location, diag_public_dtor_); |
| PrintInheritanceChain(refcounted_path.front()); |
| diagnostic().Report(loc, diag_note_public_dtor_); |
| PrintInheritanceChain(*it); |
| } |
| } |
| } |
| |
| // Check for any problems with WeakPtrFactory class members. This currently |
| // only checks that any WeakPtrFactory<T> member of T appears as the last |
| // data member in T. We could consider checking for bad uses of |
| // WeakPtrFactory to refer to other data members, but that would require |
| // looking at the initializer list in constructors to see what the factory |
| // points to. |
| // Note, if we later add other unrelated checks of data members, we should |
| // consider collapsing them in to one loop to avoid iterating over the data |
| // members more than once. |
| void FindBadConstructsConsumer::CheckWeakPtrFactoryMembers( |
| SourceLocation record_location, |
| CXXRecordDecl* record) { |
| // Skip anonymous structs. |
| if (record->getIdentifier() == NULL) |
| return; |
| |
| // Iterate through members of the class. |
| RecordDecl::field_iterator iter(record->field_begin()), |
| the_end(record->field_end()); |
| SourceLocation weak_ptr_factory_location; // Invalid initially. |
| for (; iter != the_end; ++iter) { |
| const TemplateSpecializationType* template_spec_type = |
| iter->getType().getTypePtr()->getAs<TemplateSpecializationType>(); |
| bool param_is_weak_ptr_factory_to_self = false; |
| if (template_spec_type) { |
| const TemplateDecl* template_decl = |
| template_spec_type->getTemplateName().getAsTemplateDecl(); |
| if (template_decl && template_spec_type->getNumArgs() == 1) { |
| if (template_decl->getNameAsString().compare("WeakPtrFactory") == 0 && |
| GetNamespace(template_decl) == "base") { |
| // Only consider WeakPtrFactory members which are specialized for the |
| // owning class. |
| const TemplateArgument& arg = template_spec_type->getArg(0); |
| if (arg.getAsType().getTypePtr()->getAsCXXRecordDecl() == |
| record->getTypeForDecl()->getAsCXXRecordDecl()) { |
| if (!weak_ptr_factory_location.isValid()) { |
| // Save the first matching WeakPtrFactory member for the |
| // diagnostic. |
| weak_ptr_factory_location = iter->getLocation(); |
| } |
| param_is_weak_ptr_factory_to_self = true; |
| } |
| } |
| } |
| } |
| // If we've already seen a WeakPtrFactory<OwningType> and this param is not |
| // one of those, it means there is at least one member after a factory. |
| if (weak_ptr_factory_location.isValid() && |
| !param_is_weak_ptr_factory_to_self) { |
| diagnostic().Report(weak_ptr_factory_location, |
| diag_weak_ptr_factory_order_); |
| } |
| } |
| } |
| |
| } // namespace chrome_checker |
