Memory leak in async runtime

**ROOT CAUSE ANALYSIS:** The memory leak in the async runtime occurs due to improper resource cleanup in the `AsyncClient` class. Specifically: 1. **Static Resource Holding**: The `AsyncClient` class uses a static `shared_ptr` (`client`) to hold the `AsyncClient` instance. This prevents the object from being deallocated even after all its resources are no longer needed. 2. **Async Context Mismanagement**: The `startAsync` method does not properly handle the cleanup of resources when the async operation completes. The static `shared_ptr` ensures the `AsyncClient` instance persists, but its child resources (e.g., network connections, threads) are not released. 3. **Cyclic References**: The `AsyncClient` instance is tied to the static holder, which may create cyclic references if other components (e.g., callbacks) hold references to the client. This prevents garbage collection or deallocation. **CODE FIX:** The fix involves decoupling the static instance from the `AsyncClient` and using a proper singleton pattern with lazy initialization and explicit cleanup. Additionally, ensure all child resources are released in the destructor. ```cpp #include #include #include #include #include class AsyncClient { public: static AsyncClient& getInstance() { static AsyncClient instance; return instance; } AsyncClient(const AsyncClient&) = delete; AsyncClient& operator=(const AsyncClient&) = delete; // Start an async operation (example) void startAsync() { // Resource allocation here (e.g., threads, network) // ... // Use std::shared_ptr for child resources if needed } ~AsyncClient() { // Cleanup all child resources (e.g., close connections, join threads) resources.clear(); } private: AsyncClient() = default; // Use a std::vector to track child resources (e.g., threads, handles) std::vector> resources; // Prevent direct instantiation friend class SingletonHelper; }; // Helper class to ensure singleton is destroyed at program exit class SingletonHelper { public: ~SingletonHelper() { AsyncClient::getInstance().cleanup(); // Optional: Explicit cleanup } }; // Global instance at program exit SingletonHelper helper; // Usage example: void someAsyncFunction() { AsyncClient& client = AsyncClient::getInstance(); client.startAsync(); } ``` **Key Changes:** 1. **Static Singleton**: The `AsyncClient` uses a static instance inside `getInstance()`, ensuring single access. 2. **No Static Member**: Removed the static `shared_ptr` to avoid tying the instance to the program's lifetime. 3. **Resource Tracking**: Added a `std::vector` to manage child resources (e.g., threads, network handles). 4. **Explicit Cleanup**: The `~AsyncClient` destructor ensures all resources are released. 5. **Singleton Helper**: A helper class ensures the singleton is destroyed at program exit (optional, but recommended for deterministic cleanup). This approach ensures that the `AsyncClient` instance is properly deallocated when no longer needed, freeing all associated resources.