anchor.diff:  
   icrt_clauses(Cs, In, Vt, St0) ->
       {Csvt,St1} = icrt_clauses(Cs, Vt, St0),
  -    UpdVt = icrt_export(Csvt, Vt, In),
  +    UpdVt = icrt_export(Csvt, Vt, In, St1),
       {UpdVt,St1}.
   
   %% icrt_clauses(Clauses, ImportVarTable, State) ->
  
positive.code: %%  Return all new variables in UpdVarTable as unsafe.
  
  vtunsafe({Tag,FileLine}, Uvt, Vt) ->
      {_File,Line} = loc(FileLine),
      [{V,{{unsafe,{Tag,Line}},U,Ls}} || {V,{_,U,Ls}} <- vtnew(Uvt, Vt)].
  
  %% vtmerge(VarTable, VarTable) -> VarTable.
  
negative.code: -spec call_function(line(), atom(), arity(), lint_state()) -> lint_state().
  %%  Add to both called and calls.
  
  call_function(Line, F, A, #lint{usage=Usage0,called=Cd,func=Func,file=File}=St) ->
      #usage{calls = Cs} = Usage0,
      NA = {F,A},
      Usage = case Cs of
  		undefined -> Usage0;
  		_ -> Usage0#usage{calls=dict:append(Func, NA, Cs)}
  	    end,
      Anno = erl_anno:set_file(File, Line),
      St#lint{called=[{NA,Anno}|Cd], usage=Usage}.
  
  %% function(Line, Name, Arity, Clauses, State) -> State.
  
  