557 lines
24 KiB
C++
557 lines
24 KiB
C++
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/*
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* Cppcheck - A tool for static C/C++ code analysis
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* Copyright (C) 2007-2021 Cppcheck team.
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "fwdanalysis.h"
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#include "astutils.h"
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#include "config.h"
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#include "library.h"
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#include "symboldatabase.h"
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#include "token.h"
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#include "valueflow.h"
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#include <string>
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static bool isUnchanged(const Token *startToken, const Token *endToken, const std::set<nonneg int> &exprVarIds, bool local)
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{
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for (const Token *tok = startToken; tok != endToken; tok = tok->next()) {
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if (!local && Token::Match(tok, "%name% (") && !Token::simpleMatch(tok->linkAt(1), ") {"))
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// TODO: this is a quick bailout
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return false;
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if (tok->varId() == 0 || exprVarIds.find(tok->varId()) == exprVarIds.end())
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continue;
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const Token *parent = tok;
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while (parent->astParent() && !parent->astParent()->isAssignmentOp() && parent->astParent()->tokType() != Token::Type::eIncDecOp) {
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if (parent->str() == "," || parent->isUnaryOp("&"))
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// TODO: This is a quick bailout
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return false;
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parent = parent->astParent();
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}
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if (parent->astParent()) {
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if (parent->astParent()->tokType() == Token::Type::eIncDecOp)
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return false;
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else if (parent->astParent()->isAssignmentOp() && parent == parent->astParent()->astOperand1())
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return false;
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}
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}
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return true;
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}
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static bool hasFunctionCall(const Token *tok)
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{
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if (!tok)
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return false;
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if (Token::Match(tok, "%name% ("))
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// todo, const/pure function?
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return true;
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return hasFunctionCall(tok->astOperand1()) || hasFunctionCall(tok->astOperand2());
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}
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static bool hasGccCompoundStatement(const Token *tok)
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{
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if (!tok)
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return false;
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if (tok->str() == "{" && Token::simpleMatch(tok->previous(), "( {"))
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return true;
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return hasGccCompoundStatement(tok->astOperand1()) || hasGccCompoundStatement(tok->astOperand2());
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}
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static bool nonLocal(const Variable* var, bool deref)
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{
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return !var || (!var->isLocal() && !var->isArgument()) || (deref && var->isArgument() && var->isPointer()) || var->isStatic() || var->isReference() || var->isExtern();
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}
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static bool hasVolatileCastOrVar(const Token *expr)
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{
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bool ret = false;
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visitAstNodes(expr,
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[&ret](const Token *tok) {
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if (tok->variable() && tok->variable()->isVolatile())
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ret = true;
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else if (Token::simpleMatch(tok, "( volatile"))
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ret = true;
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return ret ? ChildrenToVisit::none : ChildrenToVisit::op1_and_op2;
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});
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return ret;
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}
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struct FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *expr, const Token *startToken, const Token *endToken, const std::set<nonneg int> &exprVarIds, bool local, bool inInnerClass, int depth)
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{
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// Parse the given tokens
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if (++depth > 1000)
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return Result(Result::Type::BAILOUT);
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for (const Token* tok = startToken; precedes(tok, endToken); tok = tok->next()) {
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if (Token::simpleMatch(tok, "try {")) {
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// TODO: handle try
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return Result(Result::Type::BAILOUT);
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}
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if (Token::simpleMatch(tok, "break ;")) {
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return Result(Result::Type::BREAK, tok);
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}
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if (Token::simpleMatch(tok, "goto"))
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return Result(Result::Type::BAILOUT);
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if (!inInnerClass && tok->str() == "{" && tok->scope()->isClassOrStruct()) {
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// skip returns from local class definition
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FwdAnalysis::Result result = checkRecursive(expr, tok, tok->link(), exprVarIds, local, true, depth);
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if (result.type != Result::Type::NONE)
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return result;
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tok=tok->link();
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}
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if (tok->str() == "continue")
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// TODO
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return Result(Result::Type::BAILOUT);
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if (const Token *lambdaEndToken = findLambdaEndToken(tok)) {
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tok = lambdaEndToken;
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const Result lambdaResult = checkRecursive(expr, lambdaEndToken->link()->next(), lambdaEndToken, exprVarIds, local, inInnerClass, depth);
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if (lambdaResult.type == Result::Type::READ || lambdaResult.type == Result::Type::BAILOUT)
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return lambdaResult;
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}
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if (Token::Match(tok, "return|throw")) {
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// TODO: Handle these better
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// Is expr variable used in expression?
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const Token* opTok = tok->astOperand1();
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if (!opTok)
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opTok = tok->next();
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std::pair<const Token*, const Token*> startEndTokens = opTok->findExpressionStartEndTokens();
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FwdAnalysis::Result result =
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checkRecursive(expr, startEndTokens.first, startEndTokens.second->next(), exprVarIds, local, true, depth);
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if (result.type != Result::Type::NONE)
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return result;
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// #9167: if the return is inside an inner class, it does not tell us anything
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if (!inInnerClass) {
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if (!local && mWhat == What::Reassign)
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return Result(Result::Type::BAILOUT);
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return Result(Result::Type::RETURN);
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}
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}
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if (tok->str() == "}") {
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// Known value => possible value
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if (tok->scope() == expr->scope())
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mValueFlowKnown = false;
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if (tok->scope()->isLoopScope()) {
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// check condition
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const Token *conditionStart = nullptr;
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const Token *conditionEnd = nullptr;
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if (Token::simpleMatch(tok->link()->previous(), ") {")) {
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conditionEnd = tok->link()->previous();
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conditionStart = conditionEnd->link();
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} else if (Token::simpleMatch(tok->link()->previous(), "do {") && Token::simpleMatch(tok, "} while (")) {
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conditionStart = tok->tokAt(2);
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conditionEnd = conditionStart->link();
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}
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if (conditionStart && conditionEnd) {
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bool used = false;
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for (const Token *condTok = conditionStart; condTok != conditionEnd; condTok = condTok->next()) {
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if (exprVarIds.find(condTok->varId()) != exprVarIds.end()) {
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used = true;
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break;
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}
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}
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if (used)
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return Result(Result::Type::BAILOUT);
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}
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// check loop body again..
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const struct FwdAnalysis::Result &result = checkRecursive(expr, tok->link(), tok, exprVarIds, local, inInnerClass, depth);
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if (result.type == Result::Type::BAILOUT || result.type == Result::Type::READ)
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return result;
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}
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}
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if (Token::simpleMatch(tok, "else {"))
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tok = tok->linkAt(1);
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if (Token::simpleMatch(tok, "asm ("))
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return Result(Result::Type::BAILOUT);
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if (mWhat == What::ValueFlow && (Token::Match(tok, "while|for (") || Token::simpleMatch(tok, "do {"))) {
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const Token *bodyStart = nullptr;
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const Token *conditionStart = nullptr;
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if (Token::simpleMatch(tok, "do {")) {
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bodyStart = tok->next();
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if (Token::simpleMatch(bodyStart->link(), "} while ("))
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conditionStart = bodyStart->link()->tokAt(2);
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} else {
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conditionStart = tok->next();
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if (Token::simpleMatch(conditionStart->link(), ") {"))
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bodyStart = conditionStart->link()->next();
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}
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if (!bodyStart || !conditionStart)
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return Result(Result::Type::BAILOUT);
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// Is expr changed in condition?
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if (!isUnchanged(conditionStart, conditionStart->link(), exprVarIds, local))
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return Result(Result::Type::BAILOUT);
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// Is expr changed in loop body?
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if (!isUnchanged(bodyStart, bodyStart->link(), exprVarIds, local))
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return Result(Result::Type::BAILOUT);
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}
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if (mWhat == What::ValueFlow && Token::simpleMatch(tok, "if (") && Token::simpleMatch(tok->linkAt(1), ") {")) {
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const Token *bodyStart = tok->linkAt(1)->next();
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const Token *conditionStart = tok->next();
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const Token *condTok = conditionStart->astOperand2();
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if (condTok->hasKnownIntValue()) {
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const bool cond = condTok->values().front().intvalue;
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if (cond) {
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FwdAnalysis::Result result = checkRecursive(expr, bodyStart, bodyStart->link(), exprVarIds, local, true, depth);
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if (result.type != Result::Type::NONE)
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return result;
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} else if (Token::simpleMatch(bodyStart->link(), "} else {")) {
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bodyStart = bodyStart->link()->tokAt(2);
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FwdAnalysis::Result result = checkRecursive(expr, bodyStart, bodyStart->link(), exprVarIds, local, true, depth);
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if (result.type != Result::Type::NONE)
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return result;
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}
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}
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tok = bodyStart->link();
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if (isReturnScope(tok, &mLibrary))
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return Result(Result::Type::BAILOUT);
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if (Token::simpleMatch(tok, "} else {"))
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tok = tok->linkAt(2);
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if (!tok)
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return Result(Result::Type::BAILOUT);
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// Is expr changed in condition?
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if (!isUnchanged(conditionStart, conditionStart->link(), exprVarIds, local))
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return Result(Result::Type::BAILOUT);
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// Is expr changed in condition body?
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if (!isUnchanged(bodyStart, bodyStart->link(), exprVarIds, local))
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return Result(Result::Type::BAILOUT);
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}
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if (!local && Token::Match(tok, "%name% (") && !Token::simpleMatch(tok->linkAt(1), ") {")) {
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// TODO: this is a quick bailout
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return Result(Result::Type::BAILOUT);
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}
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if (mWhat == What::Reassign &&
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Token::simpleMatch(tok, ";") &&
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Token::simpleMatch(tok->astParent(), ";") &&
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Token::simpleMatch(tok->astParent()->astParent(), "(") &&
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Token::simpleMatch(tok->astParent()->astParent()->previous(), "for (") &&
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!isUnchanged(tok, tok->astParent()->astParent()->link(), exprVarIds, local))
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// TODO: This is a quick bailout to avoid FP #9420, there are false negatives (TODO_ASSERT_EQUALS)
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return Result(Result::Type::BAILOUT);
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if (expr->isName() && Token::Match(tok, "%name% (") && tok->str().find("<") != std::string::npos && tok->str().find(expr->str()) != std::string::npos)
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return Result(Result::Type::BAILOUT);
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if (exprVarIds.find(tok->varId()) != exprVarIds.end()) {
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const Token *parent = tok;
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bool other = false;
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bool same = tok->astParent() && isSameExpression(mCpp, false, expr, tok, mLibrary, true, false, nullptr);
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while (!same && Token::Match(parent->astParent(), "*|.|::|[|(|%cop%")) {
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parent = parent->astParent();
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if (parent->str() == "(" && !parent->isCast())
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break;
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if (isSameExpression(mCpp, false, expr, parent, mLibrary, true, false, nullptr)) {
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same = true;
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if (mWhat == What::ValueFlow) {
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KnownAndToken v;
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v.known = mValueFlowKnown;
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v.token = parent;
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mValueFlow.push_back(v);
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}
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}
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if (Token::Match(parent, ". %var%") && parent->next()->varId() && exprVarIds.find(parent->next()->varId()) == exprVarIds.end() &&
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isSameExpression(mCpp, false, expr->astOperand1(), parent->astOperand1(), mLibrary, true, false, nullptr)) {
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other = true;
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break;
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}
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}
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if (mWhat != What::ValueFlow && same && Token::simpleMatch(parent->astParent(), "[") && parent == parent->astParent()->astOperand2()) {
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return Result(Result::Type::READ);
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}
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if (other)
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continue;
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if (Token::simpleMatch(parent->astParent(), "=") && parent == parent->astParent()->astOperand1()) {
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if (!local && hasFunctionCall(parent->astParent()->astOperand2())) {
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// TODO: this is a quick bailout
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return Result(Result::Type::BAILOUT);
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}
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if (hasOperand(parent->astParent()->astOperand2(), expr)) {
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if (mWhat == What::Reassign)
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return Result(Result::Type::READ);
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continue;
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}
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const auto startEnd = parent->astParent()->astOperand2()->findExpressionStartEndTokens();
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for (const Token* tok2 = startEnd.first; tok2 != startEnd.second; tok2 = tok2->next()) {
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if (tok2->tokType() == Token::eLambda)
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return Result(Result::Type::BAILOUT);
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// TODO: analyze usage in lambda
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}
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// ({ .. })
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if (hasGccCompoundStatement(parent->astParent()->astOperand2()))
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return Result(Result::Type::BAILOUT);
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const bool reassign = isSameExpression(mCpp, false, expr, parent, mLibrary, false, false, nullptr);
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if (reassign)
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return Result(Result::Type::WRITE, parent->astParent());
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return Result(Result::Type::READ);
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} else if (mWhat == What::Reassign && parent->valueType() && parent->valueType()->pointer && Token::Match(parent->astParent(), "%assign%") && parent == parent->astParent()->astOperand1()) {
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return Result(Result::Type::READ);
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} else if (Token::Match(parent->astParent(), "%assign%") && !parent->astParent()->astParent() && parent == parent->astParent()->astOperand1()) {
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if (mWhat == What::Reassign)
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return Result(Result::Type::BAILOUT, parent->astParent());
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if (mWhat == What::UnusedValue && (!parent->valueType() || parent->valueType()->reference != Reference::None))
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return Result(Result::Type::BAILOUT, parent->astParent());
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continue;
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} else if (mWhat == What::UnusedValue && parent->isUnaryOp("&") && Token::Match(parent->astParent(), "[,(]")) {
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// Pass variable to function the writes it
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const Token *ftok = parent->astParent();
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while (Token::simpleMatch(ftok, ","))
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ftok = ftok->astParent();
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if (ftok && Token::Match(ftok->previous(), "%name% (")) {
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const std::vector<const Token *> args = getArguments(ftok);
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int argnr = 0;
|
||
|
|
while (argnr < args.size() && args[argnr] != parent)
|
||
|
|
argnr++;
|
||
|
|
if (argnr < args.size()) {
|
||
|
|
const Library::Function* functionInfo = mLibrary.getFunction(ftok->astOperand1());
|
||
|
|
if (functionInfo) {
|
||
|
|
const auto it = functionInfo->argumentChecks.find(argnr + 1);
|
||
|
|
if (it != functionInfo->argumentChecks.end() && it->second.direction == Library::ArgumentChecks::Direction::DIR_OUT)
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return Result(Result::Type::BAILOUT, parent->astParent());
|
||
|
|
} else {
|
||
|
|
// TODO: this is a quick bailout
|
||
|
|
return Result(Result::Type::BAILOUT, parent->astParent());
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (Token::Match(tok, ")|do {")) {
|
||
|
|
if (tok->str() == ")" && Token::simpleMatch(tok->link()->previous(), "switch ("))
|
||
|
|
// TODO: parse switch
|
||
|
|
return Result(Result::Type::BAILOUT);
|
||
|
|
const Result &result1 = checkRecursive(expr, tok->tokAt(2), tok->linkAt(1), exprVarIds, local, inInnerClass, depth);
|
||
|
|
if (result1.type == Result::Type::READ || result1.type == Result::Type::BAILOUT)
|
||
|
|
return result1;
|
||
|
|
if (mWhat == What::ValueFlow && result1.type == Result::Type::WRITE)
|
||
|
|
mValueFlowKnown = false;
|
||
|
|
if (mWhat == What::Reassign && result1.type == Result::Type::BREAK) {
|
||
|
|
const Token *scopeEndToken = findNextTokenFromBreak(result1.token);
|
||
|
|
if (scopeEndToken) {
|
||
|
|
const Result &result2 = checkRecursive(expr, scopeEndToken->next(), endToken, exprVarIds, local, inInnerClass, depth);
|
||
|
|
if (result2.type == Result::Type::BAILOUT)
|
||
|
|
return result2;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (Token::simpleMatch(tok->linkAt(1), "} else {")) {
|
||
|
|
const Token *elseStart = tok->linkAt(1)->tokAt(2);
|
||
|
|
const Result &result2 = checkRecursive(expr, elseStart, elseStart->link(), exprVarIds, local, inInnerClass, depth);
|
||
|
|
if (mWhat == What::ValueFlow && result2.type == Result::Type::WRITE)
|
||
|
|
mValueFlowKnown = false;
|
||
|
|
if (result2.type == Result::Type::READ || result2.type == Result::Type::BAILOUT)
|
||
|
|
return result2;
|
||
|
|
if (result1.type == Result::Type::WRITE && result2.type == Result::Type::WRITE)
|
||
|
|
return result1;
|
||
|
|
tok = elseStart->link();
|
||
|
|
} else {
|
||
|
|
tok = tok->linkAt(1);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return Result(Result::Type::NONE);
|
||
|
|
}
|
||
|
|
|
||
|
|
bool FwdAnalysis::isGlobalData(const Token *expr) const
|
||
|
|
{
|
||
|
|
return ::isGlobalData(expr, mCpp);
|
||
|
|
}
|
||
|
|
|
||
|
|
std::set<nonneg int> FwdAnalysis::getExprVarIds(const Token* expr, bool* localOut, bool* unknownVarIdOut) const
|
||
|
|
{
|
||
|
|
// all variable ids in expr.
|
||
|
|
std::set<nonneg int> exprVarIds;
|
||
|
|
bool local = true;
|
||
|
|
bool unknownVarId = false;
|
||
|
|
visitAstNodes(expr,
|
||
|
|
[&](const Token *tok) {
|
||
|
|
if (tok->str() == "[" && mWhat == What::UnusedValue)
|
||
|
|
return ChildrenToVisit::op1;
|
||
|
|
if (tok->varId() == 0 && tok->isName() && tok->previous()->str() != ".") {
|
||
|
|
// unknown variable
|
||
|
|
unknownVarId = true;
|
||
|
|
return ChildrenToVisit::none;
|
||
|
|
}
|
||
|
|
if (tok->varId() > 0) {
|
||
|
|
exprVarIds.insert(tok->varId());
|
||
|
|
if (!Token::simpleMatch(tok->previous(), ".")) {
|
||
|
|
const Variable *var = tok->variable();
|
||
|
|
if (var && var->isReference() && var->isLocal() && Token::Match(var->nameToken(), "%var% [=(]") && !isGlobalData(var->nameToken()->next()->astOperand2()))
|
||
|
|
return ChildrenToVisit::none;
|
||
|
|
const bool deref = tok->astParent() && (tok->astParent()->isUnaryOp("*") || (tok->astParent()->str() == "[" && tok == tok->astParent()->astOperand1()));
|
||
|
|
local &= !nonLocal(tok->variable(), deref);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return ChildrenToVisit::op1_and_op2;
|
||
|
|
});
|
||
|
|
if (localOut)
|
||
|
|
*localOut = local;
|
||
|
|
if (unknownVarIdOut)
|
||
|
|
*unknownVarIdOut = unknownVarId;
|
||
|
|
return exprVarIds;
|
||
|
|
}
|
||
|
|
|
||
|
|
FwdAnalysis::Result FwdAnalysis::check(const Token* expr, const Token* startToken, const Token* endToken)
|
||
|
|
{
|
||
|
|
// all variable ids in expr.
|
||
|
|
bool local = true;
|
||
|
|
bool unknownVarId = false;
|
||
|
|
std::set<nonneg int> exprVarIds = getExprVarIds(expr, &local, &unknownVarId);
|
||
|
|
|
||
|
|
if (unknownVarId)
|
||
|
|
return Result(FwdAnalysis::Result::Type::BAILOUT);
|
||
|
|
|
||
|
|
if (mWhat == What::Reassign && isGlobalData(expr))
|
||
|
|
local = false;
|
||
|
|
|
||
|
|
// In unused values checking we do not want to check assignments to
|
||
|
|
// global data.
|
||
|
|
if (mWhat == What::UnusedValue && isGlobalData(expr))
|
||
|
|
return Result(FwdAnalysis::Result::Type::BAILOUT);
|
||
|
|
|
||
|
|
Result result = checkRecursive(expr, startToken, endToken, exprVarIds, local, false);
|
||
|
|
|
||
|
|
// Break => continue checking in outer scope
|
||
|
|
while (mWhat!=What::ValueFlow && result.type == FwdAnalysis::Result::Type::BREAK) {
|
||
|
|
const Token *scopeEndToken = findNextTokenFromBreak(result.token);
|
||
|
|
if (!scopeEndToken)
|
||
|
|
break;
|
||
|
|
result = checkRecursive(expr, scopeEndToken->next(), endToken, exprVarIds, local, false);
|
||
|
|
}
|
||
|
|
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
bool FwdAnalysis::hasOperand(const Token *tok, const Token *lhs) const
|
||
|
|
{
|
||
|
|
if (!tok)
|
||
|
|
return false;
|
||
|
|
if (isSameExpression(mCpp, false, tok, lhs, mLibrary, false, false, nullptr))
|
||
|
|
return true;
|
||
|
|
return hasOperand(tok->astOperand1(), lhs) || hasOperand(tok->astOperand2(), lhs);
|
||
|
|
}
|
||
|
|
|
||
|
|
const Token *FwdAnalysis::reassign(const Token *expr, const Token *startToken, const Token *endToken)
|
||
|
|
{
|
||
|
|
if (hasVolatileCastOrVar(expr))
|
||
|
|
return nullptr;
|
||
|
|
mWhat = What::Reassign;
|
||
|
|
Result result = check(expr, startToken, endToken);
|
||
|
|
return result.type == FwdAnalysis::Result::Type::WRITE ? result.token : nullptr;
|
||
|
|
}
|
||
|
|
|
||
|
|
bool FwdAnalysis::unusedValue(const Token *expr, const Token *startToken, const Token *endToken)
|
||
|
|
{
|
||
|
|
if (isEscapedAlias(expr))
|
||
|
|
return false;
|
||
|
|
if (hasVolatileCastOrVar(expr))
|
||
|
|
return false;
|
||
|
|
mWhat = What::UnusedValue;
|
||
|
|
Result result = check(expr, startToken, endToken);
|
||
|
|
return (result.type == FwdAnalysis::Result::Type::NONE || result.type == FwdAnalysis::Result::Type::RETURN) && !possiblyAliased(expr, startToken);
|
||
|
|
}
|
||
|
|
|
||
|
|
bool FwdAnalysis::possiblyAliased(const Token *expr, const Token *startToken) const
|
||
|
|
{
|
||
|
|
if (expr->isUnaryOp("*"))
|
||
|
|
return true;
|
||
|
|
|
||
|
|
const bool macro = false;
|
||
|
|
const bool pure = false;
|
||
|
|
const bool followVar = false;
|
||
|
|
for (const Token *tok = startToken; tok; tok = tok->previous()) {
|
||
|
|
if (tok->str() == "{" && tok->scope()->type == Scope::eFunction && !(tok->astParent() && tok->astParent()->str() == ","))
|
||
|
|
break;
|
||
|
|
|
||
|
|
if (Token::Match(tok, "%name% (") && !Token::Match(tok, "if|while|for")) {
|
||
|
|
// Is argument passed by reference?
|
||
|
|
const std::vector<const Token*> args = getArguments(tok);
|
||
|
|
for (int argnr = 0; argnr < args.size(); ++argnr) {
|
||
|
|
if (!Token::Match(args[argnr], "%name%|.|::"))
|
||
|
|
continue;
|
||
|
|
if (tok->function() && tok->function()->getArgumentVar(argnr) && !tok->function()->getArgumentVar(argnr)->isReference() && !tok->function()->isConst())
|
||
|
|
continue;
|
||
|
|
for (const Token *subexpr = expr; subexpr; subexpr = subexpr->astOperand1()) {
|
||
|
|
if (isSameExpression(mCpp, macro, subexpr, args[argnr], mLibrary, pure, followVar)) {
|
||
|
|
const Scope* scope = expr->scope(); // if there is no other variable, assume no aliasing
|
||
|
|
if (scope->varlist.size() > 1)
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
|
||
|
|
const Token *addrOf = nullptr;
|
||
|
|
if (Token::Match(tok, "& %name% ="))
|
||
|
|
addrOf = tok->tokAt(2)->astOperand2();
|
||
|
|
else if (tok->isUnaryOp("&"))
|
||
|
|
addrOf = tok->astOperand1();
|
||
|
|
else if (Token::simpleMatch(tok, "std :: ref ("))
|
||
|
|
addrOf = tok->tokAt(3)->astOperand2();
|
||
|
|
else
|
||
|
|
continue;
|
||
|
|
|
||
|
|
for (const Token *subexpr = expr; subexpr; subexpr = subexpr->astOperand1()) {
|
||
|
|
if (isSameExpression(mCpp, macro, subexpr, addrOf, mLibrary, pure, followVar))
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
bool FwdAnalysis::isEscapedAlias(const Token* expr)
|
||
|
|
{
|
||
|
|
for (const Token *subexpr = expr; subexpr; subexpr = subexpr->astOperand1()) {
|
||
|
|
for (const ValueFlow::Value &val : subexpr->values()) {
|
||
|
|
if (!val.isLocalLifetimeValue())
|
||
|
|
continue;
|
||
|
|
const Variable* var = val.tokvalue->variable();
|
||
|
|
if (!var)
|
||
|
|
continue;
|
||
|
|
if (!var->isLocal())
|
||
|
|
return true;
|
||
|
|
if (var->isArgument())
|
||
|
|
return true;
|
||
|
|
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|