Cython features and practices

Cython-defined (ie not extern) "cdef cppclass" was probably a mistake to add to Cython.

cygdb won't stop at breakpoints

Alright, I've made a minimal example. File runthis.py contains: from main import main as cymain

Is there any documentation for implementing non-extern cppclass?

Thanks! That clears it up. It's also great to hear that it won't be removed. I'll

Does Cython suitable for Unity development?

Thank you for your help! You really helped me. Now I see may be easier way is just to learn C# and

Add if-unlikely construct?

Hi all, Maybe this has been already discussed or implemented in some way, but I couldn't find

python 3.14t crash with a cdef extension module

Great news! Thank you. I can keep on free threading now On Wed, Apr 22, 2026 at 11:36 AM da-woods

Lunch!

Segfault with Cython Extension reductable_params during module cleanup

From a quick look, there's one recounting issue in `reduce_call` - PyDict_GetItemWithError`

Segfault triggered during cleanup on cython 3.2.4

Decided to place this here instead on github as this may be fixable however I don't know. While

How to Allocate smart pointer scratch space per parallel thread

On 03/03/2026 20:40, da-woods wrote: On 02/03/2026 18:47, David Meyer wrote: I have one final

How to deal with transitive linker dependencies

Thanks Oscar (and sorry for the late response). I suppose some of the issues you mentioned (eg ABI

Cython is slower than ctypes in win32 based gui

Okay. Thank you for your advice. On Saturday, 14 February 2026 at 15:09:06 UTC+5:30 D Woods wrote: It

more than one python file im a resulting shared library

Hi, Cython is essentially built around the model of "one source file"->"one shared

Assertion failed: refcnt >= 0 when importing Cython module compiled with mingw32 for 32-bit Windows

Thanks, both for digging out the information, and for making me aware of pypinfo. On Sunday, December

Can't build anymore my Cython programs with Visual Studio 2026

Hi, I have been building my Cython programs for years with Visual Studio 2022, without any problem.

Jupyter notebook needs to import all modules for each cell

Thank you. I got it. Wei-Ting On Friday, November 21, 2025 at 12:49:24 AM UTC-6 Jerome Kieffer wrote:

Difference between Cython 3.2.0 and 3.1.6?

Thanks for the information! Regards Fredrik onsdag 26 november 2025 kl. 20:04:32 UTC+1 skrev D Woods:

Performance impact of passing around reshaped memory views of the same underlying array

Dear Adam Li, Please accept my apologies for the delayed response — I was away for a while and couldn

Transition from setup.py to pyproject.toml only, with dynamic args to cythonize

Thanks Oscar and Jerome, Really helps ! So I've implemented the scipy solution, which presumably

Cython 3.2 - Function signature does not match previous declaration

That's a bug - I've just made a PR for a fix. On 11/11/2025 09:08, David Lawson wrote: I'

"Tuples" of fused types

That works! Thanks. On Nov 5, 2025, at 15:35, da-woods <dw-...@d-woods.co.uk> wrote: You might

help with struct arrays and buffer formats

Hi again; I managed to get something ultra-simple working which is just fine for my purposes. This

Using Cython CFLAGS to enable some feature

In the past I've found that "set" (https://learn.microsoft.com/en-us/windows-server/

Dealing with python version differences across cythonization/compilation/runtime

On Sat, Oct 25, 2025 at 3:17 PM Nils Bruin <bruin...@gmail.com> wrote: > in principle it

Parallel Programming and Cython talk

I have just watched it. Awesome talk! D Woods schrieb am Dienstag, 21. Oktober 2025 um 15:27:05 UTC-3

Question about specialization logic for object types in Cython codebase/Cython compiler optimisations

Thanks a lot for the detailed explanation, that's very helpful. I'll definitely benchmark

Kivymd app crashing when building kivy on google colab

I've replied on the Github issue that you also posted (https://github.com/cython/cython/issues/

C-style characters

They will get translated into a character literal in C (ie ' '). I don't think we have a

cython multithread behavior

Finally,I used with nogil: FspFileSystemStopDispatcher() That's useful! da-woods <dw-git@d-

Fixing types on the Python side.

I will poke around and see what I can find then. On Sun, Sep 7, 2025, 1:57 PM da-woods <dw-git@d-