82 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "PointerArithmeticOnPolymorphicObjectCheck.h"10#include "clang/AST/ASTContext.h"11#include "clang/ASTMatchers/ASTMatchFinder.h"12 13using namespace clang::ast_matchers;14 15namespace clang::tidy::bugprone {16 17namespace {18AST_MATCHER(CXXRecordDecl, isAbstract) { return Node.isAbstract(); }19AST_MATCHER(CXXRecordDecl, isPolymorphic) { return Node.isPolymorphic(); }20} // namespace21 22PointerArithmeticOnPolymorphicObjectCheck::23 PointerArithmeticOnPolymorphicObjectCheck(StringRef Name,24 ClangTidyContext *Context)25 : ClangTidyCheck(Name, Context),26 IgnoreInheritedVirtualFunctions(27 Options.get("IgnoreInheritedVirtualFunctions", false)) {}28 29void PointerArithmeticOnPolymorphicObjectCheck::storeOptions(30 ClangTidyOptions::OptionMap &Opts) {31 Options.store(Opts, "IgnoreInheritedVirtualFunctions",32 IgnoreInheritedVirtualFunctions);33}34 35void PointerArithmeticOnPolymorphicObjectCheck::registerMatchers(36 MatchFinder *Finder) {37 const auto PolymorphicPointerExpr =38 expr(hasType(hasCanonicalType(pointerType(pointee(hasCanonicalType(39 hasDeclaration(cxxRecordDecl(unless(isFinal()), isPolymorphic())40 .bind("pointee"))))))))41 .bind("pointer");42 43 const auto PointerExprWithVirtualMethod =44 expr(hasType(hasCanonicalType(45 pointerType(pointee(hasCanonicalType(hasDeclaration(46 cxxRecordDecl(47 unless(isFinal()),48 anyOf(hasMethod(isVirtualAsWritten()), isAbstract()))49 .bind("pointee"))))))))50 .bind("pointer");51 52 const auto SelectedPointerExpr = IgnoreInheritedVirtualFunctions53 ? PointerExprWithVirtualMethod54 : PolymorphicPointerExpr;55 56 const auto ArraySubscript = arraySubscriptExpr(hasBase(SelectedPointerExpr));57 58 const auto BinaryOperators =59 binaryOperator(hasAnyOperatorName("+", "-", "+=", "-="),60 hasEitherOperand(SelectedPointerExpr));61 62 const auto UnaryOperators = unaryOperator(63 hasAnyOperatorName("++", "--"), hasUnaryOperand(SelectedPointerExpr));64 65 Finder->addMatcher(ArraySubscript, this);66 Finder->addMatcher(BinaryOperators, this);67 Finder->addMatcher(UnaryOperators, this);68}69 70void PointerArithmeticOnPolymorphicObjectCheck::check(71 const MatchFinder::MatchResult &Result) {72 const auto *PointerExpr = Result.Nodes.getNodeAs<Expr>("pointer");73 const auto *PointeeDecl = Result.Nodes.getNodeAs<CXXRecordDecl>("pointee");74 75 diag(PointerExpr->getBeginLoc(),76 "pointer arithmetic on polymorphic object of type %0 can result in "77 "undefined behavior if the dynamic type differs from the pointer type")78 << PointeeDecl << PointerExpr->getSourceRange();79}80 81} // namespace clang::tidy::bugprone82