anchor.diff:  			      #c_tuple{es=[Xs, Avar]},
   			      Match(#c_apply{anno=Anno, op=F, args=[X, Avar]},
   				    #c_tuple{es=[X, 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
   %%% 		   body=#c_let{vars=[Xs,A],
   %%% 			       %% The tuple will be optimised away
  
positive.code: 					     op=Loop,
  					     args=[Xs, Avar]},
  				    #c_tuple{es=[Xs, Avar]},
  				    #c_tuple{es=[#c_cons{hd=X, tl=Xs}, Avar]})
  %%% Multiple-value version
  %%% 			      #c_let{vars=[Xs,A],
  %%% 				     %% The tuple here will be optimised
  
negative.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{anno=[compiler_generated], 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},
  