On 22Jun.2019 1404, Phil Thompson wrote:

The implementation of issue 36085 breaks PyQt on Windows as it relies on PATH to find the Qt DLLs. The problem is that PyQt is built using the stable ABI and a single wheel is supposed to support all versions of Python starting with v3.5. On the assumption (perhaps naive) that using the stable ABI would avoid future compatibility issues, the existing PyPI wheels have long been tagged with cp38.

Was this issue considered at the time? What is the official view?

The official view is that using PATH to locate DLL dependencies is a security risk and has been deprecated by Windows. The new Store package already ignores PATH when resolving DLLs, and the change to 3.8 brings all deployments of Python on Windows into line, as well as adding the os.add_dll_directory() function that your package can use to add *only* the directory it needs. I'm sorry we didn't promote the change widely enough for you to hear about it prior to 3.8.0b1 being released, but it was made deliberately. As far as I'm aware, there are no interactions with the stable ABI here. The compatibility issue is that Windows is (slowly) dropping support for the search path you were relying on, and ultimately there is no way around that. Rather than having to tell some subset of end-users that your package won't work for them, we decided to aim for consistency and provide package developers with the means to fix it themselves. Developers from numpy, scipy and Anaconda were involved in the discussion. The section of the porting notes dealing with this issue is https://docs.python.org/3.8/whatsnew/3.8.html#bpo-36085-whatsnew Cheers, Steve

Carol, I'm "happy" with Steve's position. Fundamentally I am at fault for assuming that a combination of the stable ABI and Python's deprecation policy meant that I could assume that a wheel for Python v3.x would continue to work for v3.x+1. For this particular change I don't see how a normal deprecation warning could have been implemented. The only alternative would have been to delay the implementation for v3.9 and have loud warnings in the v3.8 docs about the upcoming change. Phil On 23/06/2019 00:06, Carol Willing wrote:

Hi Phil,

Thanks for trying the beta. Please file this as an issue at bugs.python.org. Doing so would be helpful for folks who can look into the issue.

Thanks,

Carol

On 6/22/19 2:04 PM, Phil Thompson wrote:

...

The implementation of issue 36085 breaks PyQt on Windows as it relies on PATH to find the Qt DLLs. The problem is that PyQt is built using the stable ABI and a single wheel is supposed to support all versions of Python starting with v3.5. On the assumption (perhaps naive) that using the stable ABI would avoid future compatibility issues, the existing PyPI wheels have long been tagged with cp38.

Was this issue considered at the time? What is the official view?

Thanks, Phil _______________________________________________ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-leave@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/YFNKFRJG...