From 22dfb5b6cf9a9a92ff1f6c411a285dc1b2dd9f75 Mon Sep 17 00:00:00 2001
From: William Wen <williamwen@meta.com>
Date: Tue, 12 Nov 2024 13:14:10 -0800
Subject: [PATCH] [dynamo, 3.13] replace deprecated PyWeakref_GetObject
 (#140187)

Pull Request resolved: https://github.com/pytorch/pytorch/pull/140187
Approved by: https://github.com/jansel
---
 torch/csrc/dynamo/guards.cpp | 62 +++++++++++++++++++++++++++++++-----
 1 file changed, 54 insertions(+), 8 deletions(-)

diff --git a/torch/csrc/dynamo/guards.cpp b/torch/csrc/dynamo/guards.cpp
index c39ac420ced0b0..24aea7ff95508e 100644
--- a/torch/csrc/dynamo/guards.cpp
+++ b/torch/csrc/dynamo/guards.cpp
@@ -3444,8 +3444,19 @@ class GlobalWeakRefGuardAccessor : public GuardAccessor {
       return false;
     }
 
-    PyObject* x = PyWeakref_GetObject(weakref); // borrowed ref
-    return _guard_manager->check_nopybind(x);
+    PyObject* x = nullptr;
+    if (PyWeakref_GetRef(weakref, &x) == -1) { // strong reference
+      // error when attempting to call ref
+      PyErr_Clear();
+      return false;
+    }
+    if (x == nullptr) {
+      // weakref is dead
+      x = Py_NewRef(Py_None);
+    }
+    bool result = _guard_manager->check_nopybind(x);
+    Py_DECREF(x);
+    return result;
   }
 
   GuardDebugInfo check_verbose_nopybind(
@@ -3465,8 +3476,20 @@ class GlobalWeakRefGuardAccessor : public GuardAccessor {
           false, std::string("Not a weakref ") + get_source(), 0);
     }
 
-    PyObject* x = PyWeakref_GetObject(weakref); // borrowed ref
-    return _guard_manager->check_verbose_nopybind(x);
+    PyObject* x = nullptr;
+    if (PyWeakref_GetRef(weakref, &x) == -1) { // strong reference
+      // error when attempting to call ref
+      PyErr_Clear();
+      return GuardDebugInfo(
+          false, std::string("Weakref_GetRef failed ") + get_source(), 0);
+    }
+    if (x == nullptr) {
+      // weakref is dead
+      x = Py_NewRef(Py_None);
+    }
+    auto result = _guard_manager->check_verbose_nopybind(x);
+    Py_DECREF(x);
+    return result;
   }
 
   std::string repr() const override {
@@ -3504,8 +3527,19 @@ class WeakRefCallGuardAccessor : public GuardAccessor {
       return false;
     }
 
-    PyObject* x = PyWeakref_GetObject(obj); // borrowed ref
-    return _guard_manager->check_nopybind(x);
+    PyObject* x = nullptr;
+    if (PyWeakref_GetRef(obj, &x) == -1) { // strong reference
+      // error when attempting to call ref
+      PyErr_Clear();
+      return false;
+    }
+    if (x == nullptr) {
+      // weakref is dead
+      x = Py_NewRef(Py_None);
+    }
+    bool result = _guard_manager->check_nopybind(x);
+    Py_DECREF(x);
+    return result;
   }
 
   GuardDebugInfo check_verbose_nopybind(
@@ -3515,8 +3549,20 @@ class WeakRefCallGuardAccessor : public GuardAccessor {
           false, std::string("Not a weakref obj ") + get_source(), 0);
     }
 
-    PyObject* x = PyWeakref_GetObject(obj); // borrowed ref
-    return _guard_manager->check_verbose_nopybind(x);
+    PyObject* x = nullptr;
+    if (PyWeakref_GetRef(obj, &x) == -1) { // strong reference
+      // error when attempting to call ref
+      PyErr_Clear();
+      return GuardDebugInfo(
+          false, std::string("Weakref_GetRef failed ") + get_source(), 0);
+    }
+    if (x == nullptr) {
+      // weakref is dead
+      x = Py_NewRef(Py_None);
+    }
+    auto result = _guard_manager->check_verbose_nopybind(x);
+    Py_DECREF(x);
+    return result;
   }
 
   std::string repr() const override {