Method checkIgnoredReturnValue

lib/checkfunctions.cpp:248–297

--------------------------------------------------------------------------- Check for ignored return values. ---------------------------------------------------------------------------

// Check for ignored return values.
//---------------------------------------------------------------------------
void CheckFunctionsImpl::checkIgnoredReturnValue()
{
    if (!mSettings.severity.isEnabled(Severity::warning) &&
        !mSettings.severity.isEnabled(Severity::style) &&
        !mSettings.isPremiumEnabled("ignoredReturnValue"))
        return;

    logChecker("CheckFunctions::checkIgnoredReturnValue"); // style,warning

    const SymbolDatabase *symbolDatabase = mTokenizer->getSymbolDatabase();
    for (const Scope *scope : symbolDatabase->functionScopes) {
        for (const Token* tok = scope->bodyStart->next(); tok != scope->bodyEnd; tok = tok->next()) {
            // skip c++11 initialization, ({...})
            if (Token::Match(tok, "%var%|(|,|return {"))
                tok = tok->linkAt(1);
            else if (Token::Match(tok, "[(<]") && tok->link())
                tok = tok->link();

            if (tok->varId() || tok->isKeyword() || tok->isStandardType() || !Token::Match(tok, "%name% ("))
                continue;

            const Token *parent = tok->next()->astParent();
            while (Token::Match(parent, "%cop%")) {
                if (Token::Match(parent, "<<|>>|*") && !parent->astParent())
                    break;
                parent = parent->astParent();
            }
            if (parent)
                continue;

            if (!tok->scope()->isExecutable()) {
                tok = tok->scope()->bodyEnd;
                continue;
            }

            if ((!tok->function() || !Token::Match(tok->function()->retDef, "void %name%")) &&
                tok->next()->astOperand1()) {
                const Library::UseRetValType retvalTy = mSettings.library.getUseRetValType(tok);
                const bool warn = (tok->function() && (tok->function()->isAttributeNodiscard() || tok->function()->isAttributePure() || tok->function()->isAttributeConst())) ||
                                  // avoid duplicate warnings for resource-allocating functions
                                  (retvalTy == Library::UseRetValType::DEFAULT && mSettings.library.getAllocFuncInfo(tok) == nullptr);
                if (mSettings.severity.isEnabled(Severity::warning) && warn)
                    ignoredReturnValueError(tok, tok->next()->astOperand1()->expressionString());
                else if (mSettings.severity.isEnabled(Severity::style) &&
                         retvalTy == Library::UseRetValType::ERROR_CODE)
                    ignoredReturnErrorCode(tok, tok->next()->astOperand1()->expressionString());
            }
        }
    }
}

void CheckFunctionsImpl::ignoredReturnValueError(const Token* tok, const std::string& function)
{