Update

guilhermeleobas · guilhermeleobas · commit 22f9f31d247f · 2025-08-11T23:25:00.000-03:00
[ghstack-poisoned]
diff --git a/torch/_dynamo/variables/dicts.py b/torch/_dynamo/variables/dicts.py
@@ -678,32 +678,24 @@ def call_method(
         elif name == "__or__":
             assert len(args) == 1
             # Dicts can only be unioned with other dicts or subclasses of dicts.
-            # Sets can be unioned with other sets, frozensets or subclasses of sets.
-            _raise = not (
-                (
-                    istype(self, ConstDictVariable)
-                    and istype(
-                        args[0], (ConstDictVariable, variables.UserDefinedDictVariable)
-                    )
-                )
-                or (
-                    isinstance(self, SetVariable)
-                    and isinstance(
-                        args[0], (SetVariable, variables.UserDefinedSetVariable)
-                    )
-                )
-            )
-
-            if _raise:
+            if not istype(
+                args[0], (ConstDictVariable, variables.UserDefinedDictVariable)
+            ):
                 msg = (
                     f"unsupported operand type(s) for |: '{self.python_type().__name__}'"
                     f"and '{args[0].python_type().__name__}'"
                 )
                 raise_observed_exception(TypeError, tx, args=[msg])
 
+            # Rule of thumb:
+            # - If either user_cls is defaultdict, use dict
+            # - If either is OrderedDict, use OrderedDict
+            # - Otherwise, use dict
             ts = {self.user_cls, args[0].user_cls}
             user_cls = (
-                collections.OrderedDict if collections.OrderedDict in ts else dict
+                collections.OrderedDict
+                if any(issubclass(t, collections.OrderedDict) for t in ts)
+                else dict
             )
 
             self.install_dict_keys_match_guard()
diff --git a/torch/_dynamo/variables/user_defined.py b/torch/_dynamo/variables/user_defined.py
@@ -1869,7 +1869,7 @@ def __init__(self, value, dict_vt=None, **kwargs):
                 else dict
             )
             self._dict_vt = variables.ConstDictVariable(
-                user_cls(), user_cls=user_cls, mutation_type=ValueMutationNew()
+                {}, type(value), mutation_type=ValueMutationNew()
             )
         self._dict_methods = dict_methods
 

Original file line number	Diff line number	Diff line change
`@@ -1869,7 +1869,7 @@ def __init__(self, value, dict_vt=None, **kwargs):`
`1869`	`1869`	`else dict`
`1870`	`1870`	`)`
`1871`	`1871`	`self._dict_vt = variables.ConstDictVariable(`
`1872`		`- user_cls(), user_cls=user_cls, mutation_type=ValueMutationNew()`
	`1872`	`+ {}, type(value), mutation_type=ValueMutationNew()`
`1873`	`1873`	`)`
`1874`	`1874`	`self._dict_methods = dict_methods`
`1875`	`1875`