GCI of extended-length path "\\?\" returns incorrect items

Steps to reproduce

Get-ChildItem -LiteralPath '\\?\D:\'
Get-ChildItem -LiteralPath '\\?\UNC\server\share'

Expected behavior

Gets the items in the specified location.

Actual behavior

Gets the items in the root of the current drive (e.g. C:\).  Same cmdlet in PSVersion 5.1 gets the items in the specified location.

Environment data

Name                           Value
----                           -----
PSVersion                      7.1.1
PSEdition                      Core
GitCommitId                    7.1.1
OS                             Microsoft Windows 10.0.14393
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

[daxian-dbw]

Definitely a bug that needs to be fixed in my opinion. #14078 doesn’t seem to include the specific problem this issue is about – Get-ChildItem -LiteralPath '\\?\D:\' shows files/folders under C:\ instead, so I think we should not close this issue as a dup.

@SteveL-MSFT mentioned in https://github.com/PowerShell/PowerShell/issues/10805#issuecomment-579516971

I get that users may want to use the \?\ legacy syntax, but it’s not clear to me how impactful that is to motivate spending the time to fix this.

I’m not sure if that statement also applies to this issue. Happy to see other people’s thoughts.

[msftbot[bot]]

This issue has been marked as fixed and has not had any activity for 1 day. It has been closed for housekeeping purposes.