Mailman 3 July 2017 - cython-devel

PEP 489 impacts "public" declarations (generated module header file)
by Stefan Behnel July 23, 2017

July 23, 2017

Hi all! Here's a question to cython-users. Is anyone of you using the "public" modifier to export symbols to external code? And are you calling the module init function from them directly, e.g. when embedding a Cython module in a C/C++ application? I'd like to get some feedback on how people use this feature. Here's why: I'm pretty much done implementing PEP 489 for CPython 3.5+, which splits the extension module initialisation into multiple steps to enable more Python-like module features. It changes the behaviour of the module init function, which no longer does the complete module creation and initialisation, but only returns a metadata object (PyModuleDef) that steers the init process. https://www.python.org/dev/peps/pep-0489/ My implementation is here: https://github.com/cython/cython/pull/1794 One problem that I found: The docs on `public` declarations show how to call the (Py2) module init function in order to initialise the module when embedding: http://docs.cython.org/en/latest/src/userguide/external_C_code.html#public-… That is no longer enough in Py3.5+. The PEP contains a minimal example of what needs to be done now, in addition to some new C-API functions that help doing it: https://www.python.org/dev/peps/pep-0489/#legacy-init https://www.python.org/dev/peps/pep-0489/#new-functions I can see two ways to fix the new situation: let users adapt their code (assuming that it's probably a rare use case), or export a new public function that implements the module initialisation process similar to what Cython does in pre-Py3.5, but probably losing most of the new features, such as setting a proper value for "__file__" at initialisation time, although we could accept an (optional?) ModuleSpec as argument. Exporting such a function adds convenience, at least for some users, at the price of exporting another public name from Cython modules (at least those that use public symbols). But it's not clear that such a function would cover the user's needs, because some might want to influence the process (that's what the PEP was written for, after all). And since I expect the number of users to be low, adding a convenience feature for even less of them might be unhelpful. I'd also rather avoid putting this function into the header file itself, because that makes code that uses it highly dependent on the internals, which might change with newer Cython/Python versions. So, does anyone use this feature and could explain a bit how you use it to help us understand what we should consider "convenient" for users? Stefan

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Cython 0.26 beta
by Robert Bradshaw July 20, 2017

July 20, 2017

There have been a lot of changes since Cython 0.25.2, please test and report. https://github.com/cython/cython/archive/0.26b0.zip At this point I anticipate only bugfixes will be merged before the final release.

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Re: [Cython] [cython-users] Cython 0.26 release candidate.
by Stefan Behnel July 18, 2017

July 18, 2017

Robert Bradshaw schrieb am 16.07.2017 um 01:19: > On Sat, Jul 15, 2017 at 2:44 AM, Jeroen Demeyer wrote: >> Do you intend to do something about the speed regression due to >> https://github.com/cython/cython/pull/1719 >> >> I'm happy with a yes/no answer just to know what to expect. >> > Had a chance to take a look at this: > https://github.com/cython/cython/commit/5e2dc4f78e2c9b560b07f73e664f3e70f7a… > I think this is safe enough to get into the next release. I'd suggest this change: https://github.com/cython/cython/pull/1773 Stefan

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Cython 0.26 release candidate.
by Robert Bradshaw July 15, 2017

July 15, 2017

Looks like everything's gone smoothly with the beta. I have prepared a release candidate, likely to become the final release. The git sources are available at https://github.com/cython/cython/archive/0.26rc0.zip I have also created an sdist, up at http://bradshawfamily.net/cython/Cython-0.26rc0.tar.gz - Robert

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0.25.2b0 with 32bit fixes: (sometimes) Interrupted system call in builtin_subtype_methods_T653
by Yaroslav Halchenko July 6, 2017

July 6, 2017

A fresh one I ran into while rebuilding with fixes for 32bit (thanks BTW! sorry for not prompt followup/gratitude) ====================================================================== ERROR: runTest (__main__.CythonRunTestCase) compiling (cpp) and running builtin_subtype_methods_T653 ---------------------------------------------------------------------- Traceback (most recent call last): File "runtests.py", line 998, in run self.run_tests(result, ext_so_path) File "runtests.py", line 1013, in run_tests self.run_doctests(self.module, result, ext_so_path) File "runtests.py", line 1023, in run_doctests run_forked_test(result, run_test, self.shortDescription(), self.fork) File "runtests.py", line 1076, in run_forked_test cid, result_code = os.waitpid(child_id, 0) OSError: [Errno 4] Interrupted system call ---------------------------------------------------------------------- Ran 581 tests in 188.225s FAILED (errors=1) it is not 100% reproducible. Rebuilding the package went smooth without this hiccup. Just wanted to let you know might be related that the tests were ran as set -e; for P in 2.7 3.5; do \ PYTHONPATH=`/bin/ls -d /build/cython-0.25.2~b0/build/lib.*-$P` \ /usr/bin/python$P runtests.py --shard_count=16 \ --no-refnanny -v -v --exclude="(parallel|Debugger|annotate_html)" --work-dir=build/work-dir 2>&1; \ done so testing in parallel to speed up the build of the package. This one was the only failure I have ran into but it built fine before (but there could have been some changes in the core packages since then) -- Yaroslav O. Halchenko Center for Open Neuroscience http://centerforopenneuroscience.org Dartmouth College, 419 Moore Hall, Hinman Box 6207, Hanover, NH 03755 Phone: +1 (603) 646-9834 Fax: +1 (603) 646-1419 WWW: http://www.linkedin.com/in/yarik

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Cython 0.26 release
by Robert Bradshaw July 3, 2017

July 3, 2017

I'd like to officially start off the release process with an alpha candidate. This does necessarily contain everything that will be in the final release, but given the amount of time that has passed I would recommend everyone test this out with their projects sooner rather than later. Download: https://github.com/cython/cython/archive/0.26.alpha0.zip Initial changelog: https://github.com/cython/cython/blob/0.26.alpha0/CHANGES.rst Please feel free to respond to this thread or file bugs as necessary. Thanks, Robert

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