Have you ever found an odd warning after a build or clean in Xcode like the following?

Dependency cycle for target ‘[target]’ detected: [target] -> [target]


Under the scheme settings, in particular the Build phase you should see the following options:

  1. Parllelize Build
  2. Find Implicit Dependendencies

Turn both of these off and the warning should go away.

It is worth noting that the project in question had a UnitTest target.