1 //=== CXXSelfAssignmentChecker.cpp -----------------------------*- C++ -*--===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines CXXSelfAssignmentChecker, which tests all custom defined
11 // copy and move assignment operators for the case of self assignment, thus
12 // where the parameter refers to the same location where the this pointer
13 // points to. The checker itself does not do any checks at all, but it
14 // causes the analyzer to check every copy and move assignment operator twice:
15 // once for when 'this' aliases with the parameter and once for when it may not.
16 // It is the task of the other enabled checkers to find the bugs in these two
19 //===----------------------------------------------------------------------===//
21 #include "ClangSACheckers.h"
22 #include "clang/StaticAnalyzer/Core/Checker.h"
23 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
25 using namespace clang;
30 class CXXSelfAssignmentChecker : public Checker<check::BeginFunction> {
32 CXXSelfAssignmentChecker();
33 void checkBeginFunction(CheckerContext &C) const;
37 CXXSelfAssignmentChecker::CXXSelfAssignmentChecker() {}
39 void CXXSelfAssignmentChecker::checkBeginFunction(CheckerContext &C) const {
42 const auto *LCtx = C.getLocationContext();
43 const auto *MD = dyn_cast<CXXMethodDecl>(LCtx->getDecl());
46 if (!MD->isCopyAssignmentOperator() && !MD->isMoveAssignmentOperator())
48 auto &State = C.getState();
49 auto &SVB = C.getSValBuilder();
51 State->getSVal(SVB.getCXXThis(MD, LCtx->getCurrentStackFrame()));
52 auto Param = SVB.makeLoc(State->getRegion(MD->getParamDecl(0), LCtx));
53 auto ParamVal = State->getSVal(Param);
54 ProgramStateRef SelfAssignState = State->bindLoc(Param, ThisVal);
55 C.addTransition(SelfAssignState);
56 ProgramStateRef NonSelfAssignState = State->bindLoc(Param, ParamVal);
57 C.addTransition(NonSelfAssignState);
60 void ento::registerCXXSelfAssignmentChecker(CheckerManager &Mgr) {
61 Mgr.registerChecker<CXXSelfAssignmentChecker>();