Where should I put Py_INCREF and Py_DECREF on this block in Python C Extension?

Question

Whenever I called my function, memory usage is increased around +10M per call, so I think there is some memory leak here.

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PyObject *pair = PyTuple_New(2         


        

Answer 1

When an object is created, its refcount will be 1, so after this:

my_item  = PyInt_FromLong(jp)

the object at my_item will have a refcount of 1.

When you store an item into a container, the item's reference count is incremented so that the item will be retained, so after this:

PyList_Append(my_list, my_item);

the object at my_item will have a refcount of 2.

Therefore, this line:

PyList_Append(item, PyInt_FromLong(jp));

will create an object with refcount 1 and store it in the list, incrementing the object's refcount to 2.