build failure when enabling dtrace on FreeBSD

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2016-12-26.19:19:02.376>
labels = ['3.8', 'build', '3.7', '3.9', '3.10']
title = 'build failure when enabling dtrace on FreeBSD'
updated_at = <Date 2021-08-10.09:36:19.945>
user = 'https://github.com/swills'

bugs.python.org fields:

activity = <Date 2021-08-10.09:36:19.945>
actor = '0mp'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Build']
creation = <Date 2016-12-26.19:19:02.376>
creator = 'swills'
dependencies = []
files = []
hgrepos = []
issue_num = 29077
keywords = []
message_count = 4.0
messages = ['284038', '284209', '295239', '399309']
nosy_count = 6.0
nosy_names = ['cburroughs', 'lukasz.langa', 'zach.ware', 'koobs', 'swills', '0mp']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue29077'
versions = ['Python 3.6', 'Python 3.7', 'Python 3.8', 'Python 3.9', 'Python 3.10']