Method checkTokenInsideExpression

lib/checkleakautovar.cpp:890–956

const Token * CheckLeakAutoVarImpl::checkTokenInsideExpression(const Token * const tok, VarInfo &varInfo, bool inFuncCall)
{
    // Deallocation and then dereferencing pointer..
    if (tok->varId() > 0) {
        // TODO : Write a separate checker for this that uses valueFlowForward.
        const auto var = utils::as_const(varInfo.alloctype).find(tok->varId());
        if (var != varInfo.alloctype.end()) {
            bool unknown = false;
            if (var->second.status == VarInfo::DEALLOC && tok->valueType() && tok->valueType()->pointer &&
                CheckNullPointerImpl::isPointerDeRef(tok, unknown, mSettings, /*checkNullArg*/ false) && !unknown) {
                deallocUseError(tok, tok->str());
            } else if (Token::simpleMatch(tok->tokAt(-2), "= &")) {
                varInfo.erase(tok->varId());
            } else {
                // check if tok is assigned into another variable
                const Token *rhs = tok;
                bool isAssignment = false;
                while (rhs->astParent()) {
                    if (rhs->astParent()->str() == "=") {
                        isAssignment = true;
                        break;
                    }
                    rhs = rhs->astParent();
                }
                while (rhs->isCast()) {
                    rhs = rhs->astOperand2() ? rhs->astOperand2() : rhs->astOperand1();
                }
                if ((rhs->str() == "." || rhs->varId() == tok->varId()) && isAssignment) {
                    // simple assignment
                    varInfo.erase(tok->varId());
                } else if (rhs->astParent() && rhs->str() == "(" && !mSettings.library.returnValue(rhs->astOperand1()).empty()) {
                    // #9298, assignment through return value of a function
                    const std::string &returnValue = mSettings.library.returnValue(rhs->astOperand1());
                    if (startsWith(returnValue, "arg")) {
                        int argn;
                        const Token *func = getTokenArgumentFunction(tok, argn);
                        if (func) {
                            const std::string arg = "arg" + std::to_string(argn + 1);
                            if (returnValue == arg) {
                                varInfo.erase(tok->varId());
                            }
                        }
                    }
                }
            }
        } else if (Token::Match(tok->previous(), "& %name% = %var% ;")) {
            varInfo.referenced.insert(tok->tokAt(2)->varId());
        }
    }

    // check for function call
    const Token * const openingPar = inFuncCall ? nullptr : isFunctionCall(tok);
    if (openingPar) {
        const Library::AllocFunc* allocFunc = mSettings.library.getDeallocFuncInfo(tok);
        VarInfo::AllocInfo alloc(allocFunc ? allocFunc->groupId : 0, VarInfo::DEALLOC, tok);
        if (alloc.type == 0)
            alloc.status = VarInfo::NOALLOC;
        functionCall(tok, openingPar, varInfo, alloc, nullptr);