anchor.diff:  %
   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   
  +% https://github.com/erlang/otp/commit/1315c6457e49595fdd3f91693c0506964416c9f0
  +% erts: Add new module 'atomics'
  +
   %% OTP 21.2
   
   -ifdef(have_atomics_new).
  
positive.code: %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  % maps:get/2, OTP-17
  has_maps_get_2() ->
      code:ensure_loaded(maps),
  
negative.code: %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  % https://github.com/erlang/otp/commit/fefb5d039e87ff7137e78b3d5f2eaf01e498ec4d
  % erts: Add new module 'counters'
  
  %% OTP 21.2
  
  -ifdef(have_counters_get).
  