Got `Unable to find package 'pythonx86'` Error While Compiling Python on Windows 11

[YTKme]

Bug report

Bug description:

Trying to compile Python main branch for Windows 11 and got error for Unable to find package 'pythonx86'

Step To Reproduce:

1. Clone Python source
2. Execute PCbuild\build.bat -c Debug -p x64

Full Error:

Using "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\MSBuild\Current\Bin\amd64\MSBuild.exe"  (found in the PATH)
Installing Python via nuget...
Feeds used:

Installing package 'pythonx86' to 'C:\Users\Aries\Desktop\Project\Repository\P\cpython\externals'.
Unable to find package 'pythonx86'
Cannot locate python.exe on PATH or as PYTHON variable

CPython versions tested on:

3.12

Operating systems tested on:

Windows

Linked PRs

• gh-114073: How to skip nuget.config #154039

[amkarn258]

Not able to reproduce the issue, this build succeeded for me with the latest MSBuild tools installed.

Cpython version tested on: 3.12
Operating system: Windows 11

[terryjreedy]

I have used PCbuild\build.bat -d for years with no problem. Does this give the same error? I believe you need to install some python.exe first, because it says Using py -3.11. I am puzzled that it is expecting pythonx86 in externals.

[zooba]

@YTKme Do you have a nuget config file somewhere that is removing nuget.org from its sources? If you don't actually have access to Nuget, then you won't be able to do this.

Specify the HOST_PYTHON environment variable to an existing Python install (3.10 or later) and it should skip it completely.

[YTKme]

@YTKme Do you have a nuget config file somewhere that is removing nuget.org from its sources? If you don't actually have access to Nuget, then you won't be able to do this.

Specify the HOST_PYTHON environment variable to an existing Python install (3.10 or later) and it should skip it completely.

I do not believe so because I never did any config for nuget. I just installed VS 2022 and cloned the source and fresh compile.

[YTKme]

I have used PCbuild\build.bat -d for years with no problem. Does this give the same error? I believe you need to install some python.exe first, because it says Using py -3.11. I am puzzled that it is expecting pythonx86 in externals.

It gave same error.

I am wondering why does it need pythonx86 to just compile python?

[zooba]

I'd check for a Nuget configuration file. Your output should show a feed here:

Installing Python via nuget...
Feeds used:  <--- where are the feeds???

Installing package 'pythonx86' to 'C:\Users\Aries\Desktop\Project\Repository\P\cpython\externals'.

Or try installing a copy of Python 3.11 first.

I am wondering why does it need pythonx86 to just compile python?

Because some download steps and code generation steps involve a Python script. Technically they aren't necessary if you haven't modified any of the code, but we can't detect that, and nobody has written an option for Windows to skip that part of the build entirely. Also you'd have to download 3rd party dependencies manually and set up their paths, since you wouldn't have the script to do it for you.

If you really need to work around this requirement, I suggest starting with the get_externals.bat file and the regen.targets file in PCbuild. You'll have to hack the build system a bit.

(Or you can fix your Nuget, or install a copy of Python.)

[YTKme]

I'd check for a Nuget configuration file. Your output should show a feed here:

Installing Python via nuget...
Feeds used:  <--- where are the feeds???

Installing package 'pythonx86' to 'C:\Users\Aries\Desktop\Project\Repository\P\cpython\externals'.

Or try installing a copy of Python 3.11 first.

I am wondering why does it need pythonx86 to just compile python?

Because some download steps and code generation steps involve a Python script. Technically they aren't necessary if you haven't modified any of the code, but we can't detect that, and nobody has written an option for Windows to skip that part of the build entirely. Also you'd have to download 3rd party dependencies manually and set up their paths, since you wouldn't have the script to do it for you.

If you really need to work around this requirement, I suggest starting with the get_externals.bat file and the regen.targets file in PCbuild. You'll have to hack the build system a bit.

(Or you can fix your Nuget, or install a copy of Python.)

I checked the output externals directory, other externals like bzip, libffi, openssl-bin, etc. seem to have installed fine though?

I found a nuget.config under %APPDATA%\Roaming\NuGet, but seem to be blank

<?xml version="1.0"?>
<configuration>
  <packageSources>
  </packageSources>
</configuration>

[zooba]

I found a nuget.config under %APPDATA%\Roaming\NuGet, but seem to be blank

That will be the problem.

other externals like bzip, libffi, openssl-bin, etc. seem to have installed fine

Looks like we have a fallback on Git in case Python isn't available. That obviously doesn't help with the other scripts, so probably we could drop the fallback and fail earlier.

[YTKme]

I found a nuget.config under %APPDATA%\Roaming\NuGet, but seem to be blank

That will be the problem.

other externals like bzip, libffi, openssl-bin, etc. seem to have installed fine

Looks like we have a fallback on Git in case Python isn't available. That obviously doesn't help with the other scripts, so probably we could drop the fallback and fail earlier.

Is there a documentation on what should be the correct config for nuget? This is a fresh installed system, so nuget should be default config. Same with VS 2022, it is also fresh installed.

If there's a correct configuration, I can try updating and see as well

[zooba]

The docs are https://learn.microsoft.com/en-us/nuget/reference/nuget-config-file

But since the file is nearly empty, I'd expect deleting it to fully restore the default settings. I'm not sure how it got emptied - is this your own personal system, or a work/IT-managed system?

[YTKme]

is this your own personal system, or a work/IT-managed system?

is a personal system that's just freshly installed

[zooba]

No idea how the file got changed then. But deleting it and re-running should get you back to default settings no problem. (A work-managed system might have done it on purpose, which could make things harder...)