Fixing ignored exception message.

Author: advait-dixit

mypyc/codegen/emitclass.py

@@ -820,15 +820,15 @@ def generate_finalize_for_class(
         )
     )
     emitter.emit_line("if (PyErr_Occurred() != NULL) {")
-    emitter.emit_line('PyObject *class_obj = PyObject_GetAttrString(self, "__class__");')
-    emitter.emit_line('PyObject *del_method = PyObject_GetAttrString(class_obj, "__del__");')
+    emitter.emit_line('PyObject *del_str = PyUnicode_FromString("__del__");')
+    emitter.emit_line("PyObject *del_method = _PyType_Lookup(Py_TYPE(self), del_str);")
     # CPython interpreter uses PyErr_WriteUnraisable: https://docs.python.org/3/c-api/exceptions.html#c.PyErr_WriteUnraisable
     # However, the message is slightly different due to the way mypyc compiles classes.
     # CPython interpreter prints: Exception ignored in: <function F.__del__ at 0x100aed940>
     # mypyc prints: Exception ignored in: <slot wrapper '__del__' of 'F' objects>
     emitter.emit_line("PyErr_WriteUnraisable(del_method);")
-    emitter.emit_line("Py_DECREF(class_obj);")
     emitter.emit_line("Py_XDECREF(del_method);")
+    emitter.emit_line("Py_XDECREF(del_str);")
     emitter.emit_line("}")
     # PyErr_Restore also clears exception raised in __del__.
     emitter.emit_line("PyErr_Restore(type, value, traceback);")