gh-145410: Use _sysconfig.get_platform() in the platform module

[vstinner]

• Issue: sysconfig.get_platform() could return wrong value because sys.version is truncated #145410

[vstinner]

The change avoids the WMI query (SELECT Architecture FROM Win32_Processor) in platform.machine() for these 4 sysconfig platforms: win32, win-amd64, win-arm32 and win-arm64.

cc @zooba

[vstinner]

See also issues gh-102536 and gh-98962.

[malemburg]

This looks fine, but can we be sure that the output does not change across supported Windows platforms ?

[vstinner]

According to #98962 (comment) comment, platform.architecture() is always ARM64, whereas sysconfig.get_platform() can be win-arm64, win-amd64 or win32 when Python is built for different architectures and run on ARM64 Windows. So it seems like platform.architecture() is not directly related to sysconfig.get_platform(), they can be different and my change is wrong.

[vstinner]

cc @diegorusso

[diegorusso]

I'm OK with the changes, just a minor comment on win-arm32 (that in my opinion we shouldn't need)

[diegorusso]

Do we really care about Windows on Arm 32bit? This is specifically Windows RT 8.1 which ended support in 2023.

[diegorusso]

From https://learn.microsoft.com/en-us/windows/arm/arm32-to-arm64

Windows devices running on an Arm processor (...) no longer support AArch32 (Arm32). This change impacts Universal Windows Platform apps that presently target AArch32 (Arm32). Support for 32-bit Arm versions of applications is removed in a future release of Windows 11.

[diegorusso]

Actually while we are here, we should update the documentation as well (if it is found to be inconsistent)

[malemburg]

According to #98962 (comment) comment, platform.architecture() is always ARM64, whereas sysconfig.get_platform() can be win-arm64, win-amd64 or win32 when Python is built for different architectures and run on ARM64 Windows. So it seems like platform.architecture() is not directly related to sysconfig.get_platform(), they can be different and my change is wrong.

The platform module is meant for inspecting the platform Python runs on, sysconfig normally refers to the platform and settings it was compiled with.

As for return values, "win-arm64" is not an architecture. The "win-" part refers to the OS.