My Jenkins root is C:\Program Files (x86)\Jenkins , but since I'm building a UE4 project that thas long paths, I set the job's workspace to C:\UE4.

When building, this works (mostly) as you'd expect, and the perforce client is created correctly and all seems good.

However, when the polling routine comes around it seems to mess with the client configuration sets the workspace root it to Jenkins root, which seems to confuse the perforce GUI, and at best tries to confirm if I want to do an initial sync (because the root's changed) or constantly complain that stuff that I'm trying to work with isn't in the client workspace directory.

Now, obviously I understand you're not supposed to be mucking around in the generated workspace at all, but I'm troubleshooting an issue on UE4's side that seems to silently corrupt files when building, an issue that's only detected/resolved by using perforce's Reconcile Offline Work function and reverting all the changes it finds.