Avoid creating a circular dependency between shared subtasks.

gradle/generation/regenerate.gradle

@@ -48,8 +48,11 @@ configure([
           }
         }
         
-        def otherDeps = deps - [tidy]
-        visited.each { Task t -> t.mustRunAfter(otherDeps) }
+        def intersection = visited.intersect(deps)
+        def tidyDeps = visited - intersection + [tidy]
+        def genDeps = deps - intersection
+
+        tidyDeps.each { Task t -> t.mustRunAfter(genDeps) }
       }
     }
 }