parallel make test or make install can fail building pgen when configure --enable-optimizations is used

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2017-01-25.02:30:14.596>
labels = ['build', '3.7']
title = 'parallel make test or make install can fail building pgen when configure --enable-optimizations is used'
updated_at = <Date 2017-01-25.06:18:45.044>
user = 'https://github.com/gpshead'

bugs.python.org fields:

activity = <Date 2017-01-25.06:18:45.044>
actor = 'gregory.p.smith'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Build']
creation = <Date 2017-01-25.02:30:14.596>
creator = 'gregory.p.smith'
dependencies = []
files = []
hgrepos = []
issue_num = 29365
keywords = []
message_count = 3.0
messages = ['286223', '286224', '286228']
nosy_count = 2.0
nosy_names = ['gregory.p.smith', 'xiang.zhang']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'compile error'
url = 'https://bugs.python.org/issue29365'
versions = ['Python 2.7', 'Python 3.6', 'Python 3.7']