Mailman 3 January 2018 - cython-devel

Re: [Cython] Multiple inheritance with old-style classes in Python 2?
by Jeroen Demeyer Jan. 25, 2018

Jan. 25, 2018

On 2018-01-25 18:54, Robert Bradshaw wrote: > No, we don't care about supporting this, but we should detect and > reject it informatively when possible. Good. I'll create a PR.

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Multiple inheritance with old-style classes in Python 2?
by Jeroen Demeyer Jan. 25, 2018

Jan. 25, 2018

Do we want to support Python 2 old-style classes for multiple inheritance? Personally, I don't think that we should, but it's something that has to be decided. The reason I ask is that my code from https://github.com/cython/cython/pull/2033 is actually broken when given an old-style class.

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Segfault with large cdef'd list
by Dan Stromberg Jan. 8, 2018

Jan. 8, 2018

I'm getting a weird segfault from a tiny function (SSCCE) using cython with python 2.7. I'm seeing something similar with cython and python 3.5, though I did not create an SSCCE for 3.5. This same code used to work with slightly older cythons and pythons, and a slightly older version of Linux Mint. The code is at http://stromberg.dnsalias.org/svn/why-is-python-slow/trunk (more specifically at http://stromberg.dnsalias.org/svn/why-is-python-slow/trunk/tst.pyx ) In short, cdef'ing a list of doubles with about a million elements, and using only the 0th element once, segfaults - but cdef'ing a slightly smaller array does not segfault under otherwise identical conditions. Any suggestions? Does Cython have a limit on the max size of a stack frame? Thanks! I quite like cython.

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Type Inference: Inter Procedural Analysis
by usama hameed Jan. 8, 2018

Jan. 8, 2018

Hi all, I recently suggested implementing Inter-Procedural Analysis to infer function types and made the following Github issue <https://github.com/cython/cython/issues/1893>, and I was advised to communicate on this channel. I went through the code base, and have implemented a rudimentary type inference system with inter procedural analysis of function types and arguments, and have handled recursive cases. However, the code base needs to be cleaned up a lot and is quite buggy right now. Furthermore, I am pretty sure a lot of edge cases need to be handled, i.e. closures etc. The reason I am sending out this email is to get some suggestions. Right now, the code I have written is pretty hacky, since the current code base of the project does not accommodate much flexibility to perform inter procedural analysis. I found an enhancement suggestion <https://github.com/cython/cython/wiki/enhancements-typeinference> on the GitHub project, and was wondering whether this should be done first in order to make a more flexible type inference system before trying to properly implement inter procedural analysis into the project. I just started on this as part of a university course project, but I want to continue working on this. I am not really familiar with the project's development ecosystem, and it would be really helpful if I'm given some guidance. Thanks a lot

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