using git-bash, and a normal installation, some users see this:
```
*** This command executed from D:\someproject\dev (project development repo) ***
$ arc upgrade --trace
libphutil loaded from 'D:\Arcanist\libphutil\src'.
arcanist loaded from 'D:\Arcanist\arcanist\src'.
Config: Reading user configuration file "C:\Users\<censored>\AppData\Roaming/.arcrc"...
Config: Reading system configuration file "C:\ProgramData\phabricator\arcanist\config"...
Working Copy: Reading .arcconfig from "D:\someproject\dev/.arcconfig".
Working Copy: Path "d:\someproject\dev" is part of `git` working copy "D:\someproject\dev".
Working Copy: Project root is at "D:\someproject\dev".
Config: Did not find local configuration at "D:\someproject\dev\.git\arc/config".
Upgrading libphutil...
Working Copy: No candidate locations for .arcconfig from this working directory.
Working Copy: Path "D:\Arcanist\libphutil" is not in any working copy.
[2015-09-22 20:19:13] EXCEPTION: (Exception) The current working directory is not part of a working copy for a supported version control system (Git, Subversion or Mercurial). at [<arcanist>\src\repository\api\ArcanistRepositoryAPI.php:82]
arcanist(head=master, ref.master=28b89785fe5f), phutil(head=master, ref.master=c72eb747e706)
#0 ArcanistRepositoryAPI::newAPIFromConfigurationManager(ArcanistConfigurationManager) called at [<arcanist>\src\workflow\ArcanistUpgradeWorkflow.php:42]
#1 ArcanistUpgradeWorkflow::run() called at [<arcanist>\scripts\arcanist.php:382]
```