Question

I am currently working on some simple custom allocators in c++ which generally works allready. I also overloaded the new/delete operators to allocate memory from my own allocator. Anyways I came across some scenarios where I don’t really know where the memory comes from like this:

    void myFunc(){
          myObj testObj();
          ....do something with it
    }

In this case testObj would only be valid inside the function, but where would its memory come from? Is there anyway I could link it to my allocator? Would I have to create to object using new and delete or is there another way?

Thanks

Answer 1

(myObj testObj(); declares a function named testObj which returns a myObj. Use myObj testObj; instead.)

The memory comes from the stack. It will be auto-matically destroyed when leaving the scope.

---

To use your new and delete you must of course call new and delete:

myObj* p_testObj = new myObj;
...
delete p_testObj;

But allocation on stack is the most efficient since it just involves 1 instruction sub esp, ??. I don’t see a reason to use custom allocation unless myObj is huge.