Non-determinism in Ord TyLit

The Ord TyLit instance uses uniqCompareFS, which is non-deterministic:

instance Ord TyLit where
  compare (NumTyLit x) (NumTyLit y)   = compare x y
  compare (StrTyLit x) (StrTyLit y)   = uniqCompareFS x y
  compare (CharTyLit x) (CharTyLit y) = compare x y
  compare a b = compare (tag a) (tag b)
    where
      tag :: TyLit -> Int
      tag NumTyLit{}  = 0
      tag StrTyLit{}  = 1
      tag CharTyLit{} = 2

That is very easy to misuse. This comparison should be called nonDetCmpTyLit.