Dataclasses derived from empty frozen bases skip immutability checks #87342

assignee = 'https://github.com/ericvsmith'
closed_at = None
created_at = <Date 2021-02-09.07:12:39.343>
labels = ['3.8', 'type-bug', 'library', '3.9', '3.10']
title = 'Dataclasses derived from empty frozen bases skip immutability checks'
updated_at = <Date 2021-05-13.05:17:57.697>
user = 'https://github.com/hbq1'

activity = <Date 2021-05-13.05:17:57.697>
actor = 'eric.smith'
assignee = 'eric.smith'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2021-02-09.07:12:39.343>
creator = 'hbq1'
dependencies = []
files = []
hgrepos = []
issue_num = 43176
keywords = ['3.8regression', '3.9regression']
message_count = 12.0
messages = ['386695', '390277', '390278', '390280', '390332', '390336', '390339', '390344', '393101', '393103', '393151', '393152']
nosy_count = 4.0
nosy_names = ['eric.smith', 'ulope', 'miss-islington', 'hbq1']
pr_nums = ['24484', '25205', '25206', '25215', '25217', '25218']
priority = 'normal'
resolution = None
stage = 'needs patch'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue43176'
versions = ['Python 3.8', 'Python 3.9', 'Python 3.10']