gh-148398: add type watcher in _CHECK_ATTR_CLASS (GH-148399)

Author: NekoAsakura

Misc/NEWS.d/next/Core_and_Builtins/2026-04-11-15-12-53.gh-issue-148398.g62jCA.rst

@@ -0,0 +1 @@
+Fix a bug in the JIT optimizer where class attribute loads were not invalidated after type mutation.

Python/optimizer_bytecodes.c

@@ -226,6 +226,10 @@ dummy_func(void) {
             }
             else {
                 sym_set_const(owner, type);
+                if ((((PyTypeObject *)type)->tp_flags & Py_TPFLAGS_IMMUTABLETYPE) == 0) {
+                    PyType_Watch(TYPE_WATCHER_ID, type);
+                    _Py_BloomFilter_Add(dependencies, type);
+                }
             }
         }
     }