void CheckAutoVariables::returnReference()
{
if (_tokenizer->isC())
return;
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
const std::size_t functions = symbolDatabase->functionScopes.size();
for (std::size_t i = 0; i < functions; ++i) {
const Scope * scope = symbolDatabase->functionScopes[i];
if (!scope->function)
continue;
const Token *tok = scope->function->tokenDef;
// have we reached a function that returns a reference?
if (tok->previous() && tok->previous()->str() == "&") {
for (const Token *tok2 = scope->classStart->next(); tok2 && tok2 != scope->classEnd; tok2 = tok2->next()) {
if (tok2->str() != "return")
continue;
// return..
if (Token::Match(tok2, "return %var% ;")) {
// is the returned variable a local variable?
if (isAutoVar(tok2->next())) {
const Variable *var1 = tok2->next()->variable();
// If reference variable is used, check what it references
if (Token::Match(var1->nameToken(), "%var% [=(]")) {
const Token *tok3 = var1->nameToken()->tokAt(2);
if (!Token::Match(tok3, "%var% [);.]"))
continue;
// Only report error if variable that is referenced is
// a auto variable
if (!isAutoVar(tok3))
continue;
}
// report error..
errorReturnReference(tok2);
}
}
// return reference to temporary..
else if (Token::Match(tok2, "return %var% (") &&
Token::simpleMatch(tok2->linkAt(2), ") ;")) {
if (returnTemporary(tok2->next())) {
// report error..
errorReturnTempReference(tok2);
}
}
// Return reference to a literal or the result of a calculation
else if (tok2->astOperand1() && (tok2->astOperand1()->isCalculation() || tok2->next()->isLiteral()) && astHasAutoResult(tok2->astOperand1())) {
errorReturnTempReference(tok2);
}
}
}
}
}
void CheckAutoVariables::returnReference()
{
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
std::list<Scope>::const_iterator scope;
for (scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
// only check functions
if (scope->type != Scope::eFunction)
continue;
const Token *tok = scope->classDef;
// skip any qualification
while (Token::Match(tok->tokAt(-2), "%type% ::"))
tok = tok->tokAt(-2);
// have we reached a function that returns a reference?
if (Token::Match(tok->tokAt(-2), "%type% &") ||
Token::Match(tok->tokAt(-2), "> &")) {
// go to the '('
const Token *tok2 = scope->classDef->next();
// go to the ')'
tok2 = tok2->link();
unsigned int indentlevel = 0;
for (; tok2; tok2 = tok2->next()) {
// indentlevel..
if (tok2->str() == "{")
++indentlevel;
else if (tok2->str() == "}") {
if (indentlevel <= 1)
break;
--indentlevel;
}
// return..
if (Token::Match(tok2, "return %var% ;")) {
// is the returned variable a local variable?
const unsigned int varid = tok2->next()->varId();
const Variable *var = symbolDatabase->getVariableFromVarId(varid);
if (var && var->isLocal() && !var->isStatic()) {
// report error..
errorReturnReference(tok2);
}
}
// return reference to temporary..
else if (returnTemporary(tok2)) {
// report error..
errorReturnTempReference(tok2);
}
}
}
}
}
void CheckAutoVariables::returnReference()
{
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
std::list<Scope>::const_iterator scope;
for (scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
// only check functions
if (scope->type != Scope::eFunction)
continue;
const Token *tok = scope->classDef;
// skip any qualification
while (Token::Match(tok->tokAt(-2), "%type% ::"))
tok = tok->tokAt(-2);
// have we reached a function that returns a reference?
if (tok->previous() && tok->previous()->str() == "&") {
for (const Token *tok2 = scope->classStart; tok2 && tok2 != scope->classEnd; tok2 = tok2->next()) {
// return..
if (Token::Match(tok2, "return %var% ;")) {
// is the returned variable a local variable?
const unsigned int varid1 = tok2->next()->varId();
const Variable *var1 = symbolDatabase->getVariableFromVarId(varid1);
if (var1 && var1->isLocal() && !var1->isStatic()) {
// If reference variable is used, check what it references
if (Token::Match(var1->nameToken(), "%var% =")) {
const Token *tok3 = var1->nameToken()->tokAt(2);
if (!Token::Match(tok3, "%var% [;.]"))
continue;
// Only report error if variable that is referenced is
// a auto variable
const Variable *var2 = symbolDatabase->getVariableFromVarId(tok3->varId());
if (!var2 || !var2->isLocal() || var2->isStatic() || (var2->isPointer() && tok3->strAt(1) == "."))
continue;
}
// report error..
errorReturnReference(tok2);
}
}
// return reference to temporary..
else if (returnTemporary(tok2)) {
// report error..
errorReturnTempReference(tok2);
}
}
}
}
}
void CheckAutoVariables::returnReference()
{
// locate function that returns a reference..
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
// Skip executable scopes..
if (Token::Match(tok, ") const| {"))
{
tok = tok->next();
if (tok->str() == "const")
tok = tok->next();
tok = tok->link();
continue;
}
// have we reached a function that returns a reference?
if (Token::Match(tok, "%type% & %var% (") ||
Token::Match(tok, "> & %var% ("))
{
// go to the '('
const Token *tok2 = tok->tokAt(3);
// go to the ')'
tok2 = tok2->link();
// is this a function implementation?
if (Token::Match(tok2, ") const| {"))
{
unsigned int indentlevel = 0;
std::set<unsigned int> localvar; // local variables in function
while (0 != (tok2 = tok2->next()))
{
// indentlevel..
if (tok2->str() == "{")
++indentlevel;
else if (tok2->str() == "}")
{
if (indentlevel <= 1)
break;
--indentlevel;
}
// declare local variable..
if (Token::Match(tok2, "[{};] %type%") && tok2->next()->str() != "return")
{
// goto next token..
tok2 = tok2->next();
// skip "const"
if (Token::Match(tok2, "const %type%"))
tok2 = tok2->next();
// skip "std::" if it is seen
if (Token::simpleMatch(tok2, "std ::"))
tok2 = tok2->tokAt(2);
// is it a variable declaration?
if (Token::Match(tok2, "%type% %var% ;"))
localvar.insert(tok2->next()->varId());
else if (Token::Match(tok2, "%type% < %any% > %var% ;"))
localvar.insert(tok2->tokAt(4)->varId());
}
// return..
else if (Token::Match(tok2, "return %var% ;"))
{
// is the returned variable a local variable?
if ((tok2->next()->varId() > 0) &&
(localvar.find(tok2->next()->varId()) != localvar.end()))
{
// report error..
errorReturnReference(tok2);
}
}
// return reference to temporary..
else if (returnTemporary(tok2))
{
// report error..
errorReturnTempReference(tok2);
}
}
}
}
}
}