👀 Views: 1 💬 Answers: 1 📅 Created: 2025-06-07

c++ std-shared-ptr std-vector C++

I tried several approaches but none seem to work. I'm working on a project and hit a roadblock. I'm working with a strange scenario while using `std::vector` along with `std::shared_ptr` in C++17. In a specific part of my application, I need to store pointers to dynamically allocated objects in a vector, and I decided to use `std::shared_ptr` for automatic memory management. However, I noticed that the vector seems to be allocating memory incorrectly, leading to memory leaks or double deletions. Here's a simplified version of my code: ```cpp #include <iostream> #include <vector> #include <memory> struct MyObject { int value; MyObject(int v) : value(v) {} }; int main() { std::vector<std::shared_ptr<MyObject>> vec; for (int i = 0; i < 5; ++i) { std::shared_ptr<MyObject> obj = std::make_shared<MyObject>(i); vec.push_back(obj); } // Simulate a condition that might cause improper access vec.clear(); // Clear the vector, but I still have the shared_ptrs // Attempt to access after clearing for (const auto& obj : vec) { std::cout << obj->value << '\n'; } return 0; } ``` In this example, after calling `vec.clear()`, I'm trying to access the elements in the vector. I was expecting that `vec` would hold the `shared_ptrs` correctly, but I keep getting a segmentation fault when I try to access `obj->value`. I double-checked to ensure that I'm not accessing a dangling pointer or something similar. Also, I've verified that there are no other parts of the code modifying the vector concurrently. Running this code in a debugger shows that after clearing the vector, the `shared_ptrs` are indeed still valid, but accessing them leads to unexpected behavior. What could be the reason for this scenario? Is there a better way to manage dynamically allocated objects in a vector, or am I missing something fundamental about `std::shared_ptr` handling in C++17? I'm working on a CLI tool that needs to handle this.