the ctypes tests unconditionally import macholib.dyld, which is not available in an installed testsuite on other platforms. So either don't install this test, or only run the import and test when on MacOS?

Can we have the opinions of our testing experts please.

This appears to have been fixed in ef491d76ac70.

@Marin: That changeset is touching test_multiprocessing, not ctypes.test.test_macholib.

@Zachary: Wrong paste. Correct change is 

Lib\ctypes\test\test_macholib.py@91160:6f63fff5c120, which makes the test only run on OSX.

Ahh.  Not quite, though; that change just changed the way unittest reports the results on non-Mac platforms.  The problem is actually here:

https://hg.python.org/cpython/file/default/Lib/ctypes/test/test_macholib.py#l34

We need a patch to try that import instead of doing it unconditionally, and adjust the existing skip decorator to check whether the import succeeded.

@Zachary - while that is doable, ctypes.macholib.dyld seems to be available in the dev version of 3.5.

>>> import ctypes.macholib.dyld
>>> ctypes.macholib.dyld.__file__
'/home/morkov/dev/cpython/Lib/ctypes/macholib/dyld.py'
>>> from ctypes.macholib.dyld import dyld_find
>>> dyld_find
<function dyld_find at 0x7fc36c558560>

The test itself is skipped correctly if I run on Linux.

/home/morkov/dev/cpython/python ./Lib/ctypes/test/test_macholib.py
s
----------------------------------------------------------------------
Ran 1 test in 0.001s

OK (skipped=1)

My bad, you're right.  Thanks!