Fix test_weakref.test_threaded_weak_key_dict_copy refleak

Objects/object.c

@@ -345,6 +345,9 @@ _Py_DecRefSharedDebug(PyObject *o, const char *filename, int lineno)
                                                 &shared, new_shared));
 
     if (should_queue) {
+#ifdef Py_REF_DEBUG
+        _Py_IncRefTotal(_PyInterpreterState_GET());
+#endif
         _Py_brc_queue_object(o);
     }
     else if (new_shared == _Py_REF_MERGED) {
@@ -395,13 +398,13 @@ _Py_ExplicitMergeRefcount(PyObject *op, Py_ssize_t extra)
     Py_ssize_t shared = _Py_atomic_load_ssize_relaxed(&op->ob_ref_shared);
     do {
         refcnt = Py_ARITHMETIC_RIGHT_SHIFT(Py_ssize_t, shared, _Py_REF_SHARED_SHIFT);
-        if (_Py_REF_IS_MERGED(shared)) {
-            return refcnt;
-        }
-
         refcnt += (Py_ssize_t)op->ob_ref_local;
         refcnt += extra;
 
+#ifdef Py_REF_DEBUG
+        _Py_AddRefTotal(_PyInterpreterState_GET(), extra);
+#endif
+
         new_shared = _Py_REF_SHARED(refcnt, _Py_REF_MERGED);
     } while (!_Py_atomic_compare_exchange_ssize(&op->ob_ref_shared,
                                                 &shared, new_shared));

Objects/obmalloc.c

@@ -1073,7 +1073,12 @@ get_mimalloc_allocated_blocks(PyInterpreterState *interp)
             mi_heap_visit_blocks(heap, false, &count_blocks, &allocated_blocks);
         }
     }
-    // TODO(sgross): count blocks in abandoned segments.
+
+    mi_abandoned_pool_t *pool = &interp->mimalloc.abandoned_pool;
+    for (uint8_t tag = 0; tag < _Py_MIMALLOC_HEAP_COUNT; tag++) {
+        _mi_abandoned_pool_visit_blocks(pool, tag, false, &count_blocks,
+                                        &allocated_blocks);
+    }
 #else
     // TODO(sgross): this only counts the current thread's blocks.
     mi_heap_t *heap = mi_heap_get_default();