76 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 "UndelegatedConstructorCheck.h"10#include "clang/AST/ASTContext.h"11 12using namespace clang::ast_matchers;13 14namespace clang::tidy::bugprone {15 16namespace {17AST_MATCHER_P(Stmt, ignoringTemporaryExpr,18 ast_matchers::internal::Matcher<Stmt>, InnerMatcher) {19 const Stmt *E = &Node;20 for (;;) {21 // Temporaries with non-trivial dtors.22 if (const auto *EWC = dyn_cast<ExprWithCleanups>(E))23 E = EWC->getSubExpr();24 // Temporaries with zero or more than two ctor arguments.25 else if (const auto *BTE = dyn_cast<CXXBindTemporaryExpr>(E))26 E = BTE->getSubExpr();27 // Temporaries with exactly one ctor argument.28 else if (const auto *FCE = dyn_cast<CXXFunctionalCastExpr>(E))29 E = FCE->getSubExpr();30 else31 break;32 }33 34 return InnerMatcher.matches(*E, Finder, Builder);35}36 37// Finds a node if it's a base of an already bound node.38AST_MATCHER_P(CXXRecordDecl, baseOfBoundNode, std::string, ID) {39 return Builder->removeBindings(40 [&](const ast_matchers::internal::BoundNodesMap &Nodes) {41 const auto *Derived = Nodes.getNodeAs<CXXRecordDecl>(ID);42 return Derived != &Node && !Derived->isDerivedFrom(&Node);43 });44}45} // namespace46 47void UndelegatedConstructorCheck::registerMatchers(MatchFinder *Finder) {48 // We look for calls to constructors of the same type in constructors. To do49 // this we have to look through a variety of nodes that occur in the path,50 // depending on the type's destructor and the number of arguments on the51 // constructor call, this is handled by ignoringTemporaryExpr. Ignore template52 // instantiations to reduce the number of duplicated warnings.53 54 Finder->addMatcher(55 traverse(56 TK_AsIs,57 compoundStmt(hasParent(cxxConstructorDecl(58 ofClass(cxxRecordDecl().bind("parent")))),59 forEach(ignoringTemporaryExpr(60 cxxConstructExpr(61 hasDeclaration(cxxConstructorDecl(ofClass(62 cxxRecordDecl(baseOfBoundNode("parent"))))))63 .bind("construct"))),64 unless(isInTemplateInstantiation()))),65 this);66}67 68void UndelegatedConstructorCheck::check(69 const MatchFinder::MatchResult &Result) {70 const auto *E = Result.Nodes.getNodeAs<CXXConstructExpr>("construct");71 diag(E->getBeginLoc(), "did you intend to call a delegated constructor? "72 "A temporary object is created here instead");73}74 75} // namespace clang::tidy::bugprone76