anchor.diff:  					     op=Loop,
   					     args=[Xs, Avar]},
   				    #c_tuple{es=[Xs, Avar]},
  -				    #c_tuple{es=[#c_cons{hd=X, tl=Xs}, Avar]})
  +				    #c_tuple{anno=[compiler_generated],
  +					     es=[#c_cons{anno=[compiler_generated],
  +							 hd=X, tl=Xs},
  +						 Avar]})
   %%% Multiple-value version
   %%% 			      #c_let{vars=[Xs,A],
   %%% 				     %% The tuple here will be optimised
  
positive.code:     B = #c_var{name='B'},
      Err1 = #c_tuple{es=[#c_literal{val='case_clause'}, X]},
      CC1 = #c_clause{pats=[#c_literal{val=true}], guard=#c_literal{val=true},
  		    body=#c_cons{hd=X, tl=Xs}},
      CC2 = #c_clause{pats=[#c_literal{val=false}], guard=#c_literal{val=true},
  		    body=Xs},
      CC3 = #c_clause{pats=[X], guard=#c_literal{val=true},
  
negative.code: 			     )},
      C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
  %%% Tuple passing version
  		   body=#c_tuple{anno=[compiler_generated],
  				 es=[#c_literal{val=[]}, Avar]}},
  %%% Multiple-value version
  %%% 		   body=#c_values{es=[#c_literal{val=[]}, A]}},
      Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
  