Turns out fixing this only in importlib is not sufficient and we
need to backport CPython part of the fix too.
This patch is based on https://hg.python.org/cpython/rev/c16063765d3a
but because the code around is different there are some changes (C-strings
instead of Python objects etc.)
With this patch Tensorflow builds successfully on many-core machine.
This commit adds a Nix-specific module that recursively adds paths that
are on `NIX_PYTHONPATH` to `sys.path`. In order to process possible
`.pth` files `site.addsitedir` is used.
The paths listed in `PYTHONPATH` are added to `sys.path` afterwards, but
they will be added before the entries we add here and thus take
precedence.
The reason for adding support for this environment variable is that we
can set it in a wrapper without breaking support for `PYTHONPATH`.
This is python bug https://bugs.python.org/issue13146. Fixed since
python 3.4. It makes pyc creation atomic, preventing a race condition.
The patch has been rebased on our deterministic build patch.
It wasn't backported to python 2.7 because there was a complaint about
changed semantics. Since files are now created in a temporary directory
and then moved, symlinks will be overridden. See
https://bugs.python.org/issue17222.
That is an edge-case however. Ubuntu and debian have backported the fix
in 2013 already, making it mainstream enough for us to adopt.
Patching numpy.distutils used to be required for pythonPackages.cython
to build on darwin. It was later accidentally disabled during one of the
refactorings, but that did not break cython. This change reinstantiates
the patch. It still applies, so it should be low maintenance and it can
still be useful.
Originally introduced in 8970a9c and 1531b5e, these patches were lost in
efbe87f when the CPython version files were merged, likely due to
CPython 3.7 not needing them anymore. These patches should remain
in-tree until CPython 3.5 and 3.6 support is dropped completely.
Found with the diffoscope ( https://diffoscope.org/ ).
The upstream patch for distutils does not apply cleanly to Python
3.7.3's sources. (The patch applies cleanly to Python 3.7.2's sources,
but nixpkgs commit 0ddae82e6a upgraded
Python to 3.7.3.) Fix the patch to make python37 build on macOS.
