Regression in compileall ddir parameter when recursing

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2019-11-06.07:12:13.431>
labels = ['3.7', '3.8', 'type-bug', 'library']
title = 'Regression in compileall ddir parameter when recursing'
updated_at = <Date 2020-05-03.17:15:40.122>
user = 'https://bugs.python.org/hetman'

bugs.python.org fields:

activity = <Date 2020-05-03.17:15:40.122>
actor = 'FFY00'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2019-11-06.07:12:13.431>
creator = 'hetman'
dependencies = []
files = []
hgrepos = []
issue_num = 38715
keywords = ['patch']
message_count = 3.0
messages = ['356102', '367984', '367986']
nosy_count = 3.0
nosy_names = ['serhiy.storchaka', 'hetman', 'FFY00']
pr_nums = ['17398']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue38715'
versions = ['Python 3.5', 'Python 3.6', 'Python 3.7', 'Python 3.8']