Two computers running cygwin; on one python venv sets up fine and on the other an error

Am 2026-06-19 17:10:19, schrieb Soren via Cygwin:
> Hello Cygwinstas,
> 
> As in the Subject: I have two systems with Windows 11 and with Cygwin
> installed. I am attempting to reproduce the execution of a series of steps
> leading to meson being installed on the second computer, so I can do some
> code building. I've tried it multiple times and keep getting this failure
> message:
> 
> $ type -p python3 && python3 --version
> /usr/bin/python3
> Python 3.12.12
> $ python3 -m venv ~/Devel/python.venv/beleriand
> Error: Command
> '['/cygdrive/c/Users/soren/Devel/python.venv/beleriand/bin/python', '-m',
> 'ensurepip', '--upgrade', '--default-pip']' returned non-zero exit status 1.
> 
> 
> On the first system, where the virtual env works fine, I see this:
> 
> $ type -p python3 && python3 --version
> /usr/bin/python3
> Python 3.12.12
> 
> It's the same version of python, yep. What could be wrong? TIA.
> -- 
> somian / Soren

Hi Soren, 

the error message seems similar to thread "python3.12 ensurepip fails" from 2026-02-07 and later. The fix was a workaround in python{3.9,3.12}-virtualenv.

You may check if python312-virtualenv-20.36.1-1 is installed. Then something like (from my machine):

    $ python3.12 -m ensurepip
    Looking in links: /tmp/tmprfwr8cps
    Requirement already satisfied: pip in /usr/lib/python3.12/site-packages (26.0.1)

    $ python3.12 -m venv venv3.12

    $ ls ~/venv3.12/bin/
    activate      activate.fish  pip   pip3.12  python3
    activate.csh  Activate.ps1   pip3  python   python3.12

    $ source ~/venv3.12/bin/activate
    ...

HTH
Harald

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