Bug Fix

On Windows, sysconfig.get_platform() checks for the string 'amd64' in sys.version to detect 64-bit builds. However, sys.version can be truncated (e.g., ~100 characters on clang builds), causing 'amd64' to be missing and returning 'win32' incorrectly.

This causes problems when installing native packages via pip because cp314-cp314-amd64 is not in the list of supported tags.

The Fix

This PR adds sys.maxsize > 2**32 as a fallback check, which is reliable even when sys.version is truncated. It also reorders the arm64 check before arm32 for proper precedence.

Before:

if os.name == 'nt':
    if 'amd64' in sys.version.lower():
        return 'win-amd64'
    if '(arm)' in sys.version.lower():
        return 'win-arm32'
    if '(arm64)' in sys.version.lower():
        return 'win-arm64'
    return sys.platform

After:

if os.name == 'nt':
    if 'amd64' in sys.version.lower():
        return 'win-amd64'
    if sys.maxsize > 2**32:
        # 64-bit Windows where sys.version may be truncated
        return 'win-amd64'
    if '(arm64)' in sys.version.lower():
        return 'win-arm64'
    if '(arm)' in sys.version.lower():
        return 'win-arm32'
    return sys.platform

Fixes: #145410

Submitted by automated agent