* Use lifetimes to check for returning reference to temporaries
* Check for dangling temporaries
* Check for unknown types for returining by reference
* Remove old returnTemporary check
* Format
* Check for deref op
* Ternary operator return an lvalue reference
* Warn when returning temporaries from member functions
* Improve handling of pointer to function
* Extend lifetimes of const references
* Add valueFlowForwardExpression function to forward values of an expression
* Use token for expression
* Fix name in bailout message
* Handle expressions
* Add more tests for more expressions
* Add more tests
* Solve the expression if possible
* Formatting
This will now warn when doing something like this:
```cpp
template <class T, class K, class V>
const V& get_default(const T& t, const K& k, const V& v) {
auto it = t.find(k);
if (it == t.end()) return v;
return it->second;
}
const int& bar(const std::unordered_map<int, int>& m, int k) {
auto x = 0;
return get_default(m, k, x);
}
```
The lifetime warning is considered inconclusive in this case.
I also updated valueflow to no tinject inconclusive values unless `--inconclusive` flag is passed. This creates some false negatives because library functions are not configured to not modify their input parameters, and there are some checks that do not check if the value is inconclusive or not.
This will diagnose more issues such as:
```cpp
void f(std::vector<int> &v) {
auto v0 = v.begin();
v.push_back(123);
std::cout << *v0 << std::endl;
}
```
This switches to use lifetime analysis to check for assigning to non-local variables:
```cpp
class test
{
public:
void f()
{
int x;
this->ptr = &x;
}
protected:
int *ptr;
};
```
This is trying to fix the issue by fixing the ast and symbol database. First, the ast nodes will be created for the init list and the symbol database will not mark it as a scope. I am not sure if this is the correct approach as I dont really understand how the AST part works.
It did change the AST for `try {} catch (...) {}` but that is because it incorrectly treats `try {}` as an initializer list.
This limits the recursion depth as a last line of defense to avoid stack
overflows when there are really huge arrays.
See https://trac.cppcheck.net/ticket/8922
This fixes issue 8996 by improving the alias checking by using lifetime analysis. It also extends the lifetime checker to handle constructors and initializer lists for containers and arrays.