What causes an invalid pointer operation in a C++ destructor?

[Michael47]

I’ve been getting this weird "invalid pointer operation" error in my custom C++ application every time I close a specific data import window. The program doesn’t crash until exit, but the debugger points to a destructor in one of my manager classes. I’m not sure if I’m dealing with a double-free or something accessing already freed memory.

[ZacharyGR]

I’ve chased that exact line of symptoms before. 'invalid pointer operation' usually means something touched memory that was freed or never allocated in the first place. In one project the destructor in a manager class did a delete on a member that another part of the code had already freed, and the crash only showed up when the app exited. The pattern I saw was a raw pointer sneaking out of a smart pointer, then the destructor ran and tried to clean it up again.

[Brandon96]

Another time I had an import window that created objects and registered them in a global list. On close, the window destructed and the global list tried to delete them again, leading to a crash at exit.

[Zachary.P]

Could it be something different than memory lifetime? Are you sure the problem is memory lifetime and not something like a callback still running when the window closes? I once hit similar symptoms when a background thread kept calling into a manager after its objects were freed; it felt like a double delete until I stopped the thread first. Could a background thread still be touching it after close?

[GregoryJ]

i’d try to add a lightweight log around destructor calls and allocations to see order, maybe instrument with a simple counter for allocations and frees tied to the manager lifecycle. a tiny difference in timing showed me whether something was freed first or last, though i’m not confident this would catch every path.