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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"weakrefobject.c: binary, ternary, or comparison operations ref leak with dead proxy","articleBody":"# Bug report\n\n### Bug description:\n\nOriginal gist: https://gist.github.com/devdanzin/f7d0c7694b2be2345f4cf85f4eedc3ee\n\n\n\u003e ## Summary\n\u003e \n\u003e When first `UNWRAP(x)` succeeds but second `UNWRAP(y)` fails (dead proxy), `x`'s new reference is leaked. Affects ~20 binary operators (+, -, *, /, |, \u0026, ^, etc.).\n\u003e \n\u003e ## Reproducer\n\u003e \n\u003e ```python\n\u003e import weakref, sys, gc\n\u003e \n\u003e class C:\n\u003e     def __add__(self, other): return NotImplemented\n\u003e     def __radd__(self, other): return NotImplemented\n\u003e \n\u003e obj = type('D', (), {})()\n\u003e dead = weakref.proxy(obj)\n\u003e del obj; gc.collect()\n\u003e \n\u003e live_obj = C()\n\u003e live = weakref.proxy(live_obj)\n\u003e \n\u003e before = sys.gettotalrefcount()\n\u003e for i in range(10000):\n\u003e     try:\n\u003e         live + dead\n\u003e     except ReferenceError:\n\u003e         pass\n\u003e after = sys.gettotalrefcount()\n\u003e print(f\"Leaked {after - before} refs (~{(after-before)//10000}/call)\")\n\u003e ```\n\nActually,  ternary, or comparison operations have the same problem.\n\n### CPython versions tested on:\n\nCPython main branch\n\n### Operating systems tested on:\n\n_No response_\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-153059\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/aisk","@type":"Person","name":"aisk"},"datePublished":"2026-07-05T02:52:01.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/153058/cpython/issues/153058"}