This is probably related to issue 17679.

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FAIL: test_sysconfig_module (distutils.tests.test_sysconfig.SysconfigTestCase)
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Traceback (most recent call last):
  File "/home/berker/projects/cpython/Lib/distutils/tests/test_sysconfig.py", line 132, in test_sysconfig_module
    self.assertEqual(global_sysconfig.get_config_var('CFLAGS'), sysconfig.get_config_var('CFLAGS'))
AssertionError: '-Wno-unused-result -g -O0 -Wall -Wstrict-prototypes' != '-Wno-unused-result -Werror=declaration-after-statement -g -O0[22 chars]ypes'
- -Wno-unused-result -g -O0 -Wall -Wstrict-prototypes
+ -Wno-unused-result -Werror=declaration-after-statement -g -O0 -Wall -Wstrict-prototypes

Please add system/os/py-version info. On my Win7-64 machine,
C:\Programs\Python34>python -m test -v test_sysconfig
C:\Programs\Python34>python -m distutils.tests.test_sysconfig
both pass (and run slightly different sets of tests).

Sorry, about system comment. Got here by link on mail list and read message, not title. Py version is still relevant, as one should try latest releases before reporting.

On my system Ubuntu 12.04 -64bit
./python -m test -v test_sysconfig
./python -m distutils/tests/test_sysconfig
both run fine

I also can't reproduce this in Python 3.3 or 3.4 on Trusty Tahr (what will be Ubuntu 14.04).

The cause of the test failure was the Lib/_sysconfigdata.py file which is created by the _generate_posix_vars() function in Lib/sysconfig.py. With a fresh copy of the repo and a clean build, all tests are passed.