`SystemSupportedProcessorArchitectures2` was added in Windows 11. As far as I can tell, the only difference between `SystemSupportedProcessorArchitectures` and `SystemSupportedProcessorArchitectures2` is on ARM64, where `SystemSupportedProcessorArchitectures` does not return x86_64 as a supported architecture. If you get `SystemSupportedProcessorArchitectures` for an emulated x86_64 process, it reports being an ARM64 process. `SystemSupportedProcessorArchitectures2` returns all 3 architectures, with flags set as expected. The ultimate goal here is to implement `GetMachineTypeAttributes()`, which Steam needs to correctly use the x86_64 version on ARM64. -- v2: server: Add x86_64 as a supported machine on ARM64. ntdll: Implement NtQuerySystemInformation(SystemSupportedProcessorArchitectures2). ntdll/tests: Add tests for NtQuerySystemInformation(SystemSupportedProcessorArchitectures2). ntdll/tests: In wow64, factor the SYSTEM_INFORMATION_CLASS out of test_query_architectures(). https://gitlab.winehq.org/wine/wine/-/merge_requests/10526