OS-specific frozen modules are built, even on other OSes.

GitHub fields:

assignee = 'https://github.com/ericsnowcurrently'
closed_at = None
created_at = <Date 2021-09-23.17:31:45.907>
labels = ['interpreter-core', 'type-bug', '3.11']
title = 'OS-specific frozen modules are built, even on other OSes.'
updated_at = <Date 2021-11-20.00:28:14.846>
user = 'https://github.com/ericsnowcurrently'

bugs.python.org fields:

activity = <Date 2021-11-20.00:28:14.846>
actor = 'gvanrossum'
assignee = 'eric.snow'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2021-09-23.17:31:45.907>
creator = 'eric.snow'
dependencies = []
files = []
hgrepos = []
issue_num = 45273
keywords = ['patch']
message_count = 2.0
messages = ['402514', '402515']
nosy_count = 3.0
nosy_names = ['gvanrossum', 'eric.snow', 'steve.dower']
pr_nums = ['29648']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue45273'
versions = ['Python 3.11']