We recently got a new warning -fwarn-unticked-promoted-constructors (see #9778 and D534). This warning is enabled with -Wall but I think that this is not a good idea. I strongly propose to remove it with -Wall. Rationale: 1. I feel that ticks add unnecessary noise: prDictOfPReprInstTyCon :: Type -> CoAxiom 'Unbranched -> [Type] -> VM CoreExpr To me it feels awkward to have Unbranched with a tick but CoreExpr without a tick (both are types after all). Moreover, ticks also trip many syntax highlighters, which further degrades code readability. 2. I've been refactoring some of GHC code to use promoted types instead of empty data types (see CoAxiom.BranchList). This would have been a fairly local change, except that I have to add ticks in every place that mentiones promoted types. That's a Royal Pain and a "good" example how this warning can get in people's way. Janek