I just started getting errors in my PEP 404 / pythonv branch, but they don't at first glance appear related to the functionality of this branch. What I'm seeing is that during installation, some of the .pyc/.pyo files written by compileall have mode 600 rather than the expected 644, with the result that test_compileall fails when run from the installed Python as an unprivileged user. If I manually do sudo chmod a+r /usr/local/lib/python3.3/__pycache__/* then test_compileall works again. I added a diagnostic to compileall.py, here's an extract from the log of the subsequent installation: Listing '/usr/local/lib/python3.3'... Compiling '/usr/local/lib/python3.3/__future__.py'... Mode of [...]/__pycache__/__future__.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/__phello__.foo.py'... Mode of [...]/__pycache__/__phello__.foo.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_compat_pickle.py'... Mode of [...]/__pycache__/_compat_pickle.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_dummy_thread.py'... Mode of [...]/__pycache__/_dummy_thread.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_markupbase.py'... Mode of [...]/__pycache__/_markupbase.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_pyio.py'... Mode of [...]/__pycache__/_pyio.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_strptime.py'... Mode of [...]/__pycache__/_strptime.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_sysconfigdata.py'... Mode of [...]/__pycache__/_sysconfigdata.cpython-33.pyc is 600 Compiling '/usr/local/lib/python3.3/_threading_local.py'... Mode of [...]/__pycache__/_threading_local.cpython-33.pyc is 644 Compiling '/usr/local/lib/python3.3/_weakrefset.py'... Mode of [...]/__pycache__/_weakrefset.cpython-33.pyc is 600 Compiling '/usr/local/lib/python3.3/abc.py'... Mode of [...]/__pycache__/abc.cpython-33.pyc is 600 Compiling '/usr/local/lib/python3.3/aifc.py'... Mode of [...]/__pycache__/aifc.cpython-33.pyc is 644 The 600s and 644s are interspersed with no pattern immediately apparent. All the source files have mode 644, as expected. This happens on two different Posix machines - Ubuntu Natty and OS X Leopard - so doesn't seem to be related to the external environment. Can anyone shed any light as to what might be going on? Regards, Vinay Sajip