Merge branch 'ks/dialyzer-r14b02-final-touches' into dev

* ks/dialyzer-r14b02-final-touches:
  Release notes and new version for R14B02
  More descriptive warning when a tuple pattern matches a typed record
  Better blame assignment when a spec is erroneous
  Generate better warnings for failing guards
  Fix an erroneous warning
  Refactoring so that a flat string() is returned
  Renamed error/1 function and added specs
  Renamed error/1 function and added specs

OTP-9126

10 files changed, 194 insertions, 90 deletions

diff --git a/lib/dialyzer/RELEASE_NOTES b/lib/dialyzer/RELEASE_NOTES
index 3fd5e9cc7d..4e311bb543 100644
--- a/lib/dialyzer/RELEASE_NOTES
+++ b/lib/dialyzer/RELEASE_NOTES
@@ -3,6 +3,18 @@
 		(in reversed chronological order)
 ==============================================================================
 
+Version 2.4.2 (in Erlang/OTP R14B02)
+------------------------------------
+ - Added --fullpath option to display files with warnings with their full
+   file names (thanks to Magnus Henoch for the original patch).
+ - Better handling of 'and'/'or'/'not' guards that generate warnings
+   (thanks to Stavros Aronis).
+ - Better blame assignment for cases when a function's spec is erroneous
+   (thanks to Stavros Aronis).
+ - More descriptive warnings when a tuple/record pattern contains subterms
+   that violate the declared types of record fields (thanks to Matthias Lang
+   for the test case and for Stavros Aronis for the actual fix).
+
 Version 2.4.0 (in Erlang/OTP R14B01)
 ------------------------------------
  - Added ability to supply multiple PLTs for the analysis (option --plts).
diff --git a/lib/dialyzer/src/dialyzer.erl b/lib/dialyzer/src/dialyzer.erl
index dde0c17c39..5014a4244c 100644
--- a/lib/dialyzer/src/dialyzer.erl
+++ b/lib/dialyzer/src/dialyzer.erl
@@ -334,6 +334,9 @@ message_to_string({guard_fail, []}) ->
   "Clause guard cannot succeed.\n";
 message_to_string({guard_fail, [Arg1, Infix, Arg2]}) ->
   io_lib:format("Guard test ~s ~s ~s can never succeed\n", [Arg1, Infix, Arg2]);
+message_to_string({neg_guard_fail, [Arg1, Infix, Arg2]}) ->
+  io_lib:format("Guard test not(~s ~s ~s) can never succeed\n",
+		[Arg1, Infix, Arg2]);
 message_to_string({guard_fail, [Guard, Args]}) ->
   io_lib:format("Guard test ~w~s can never succeed\n", [Guard, Args]);
 message_to_string({neg_guard_fail, [Guard, Args]}) ->
@@ -365,6 +368,9 @@ message_to_string({record_constr, [Name, Field, Type]}) ->
 message_to_string({record_matching, [String, Name]}) ->
   io_lib:format("The ~s violates the"
 		" declared type for #~w{}\n", [String, Name]);
+message_to_string({record_match, [Pat, Type]}) ->
+  io_lib:format("Matching of ~s tagged with a record name violates the declared"
+		" type of ~s\n", [Pat, Type]);
 message_to_string({pattern_match, [Pat, Type]}) ->
   io_lib:format("The ~s can never match the type ~s\n", [Pat, Type]);
 message_to_string({pattern_match_cov, [Pat, Type]}) ->
@@ -391,6 +397,10 @@ message_to_string({contract_supertype, [M, F, _A, Contract, Sig]}) ->
   io_lib:format("Type specification ~w:~w~s"
 		" is a supertype of the success typing: ~w:~w~s\n",
 		[M, F, Contract, M, F, Sig]);
+message_to_string({contract_range, [Contract, M, F, ArgStrings, Line, CRet]}) ->
+  io_lib:format("The contract ~w:~w~s cannot be right because the inferred"
+		" return for ~w~s on line ~w is ~s\n",
+		[M, F, Contract, F, ArgStrings, Line, CRet]);
 message_to_string({invalid_contract, [M, F, A, Sig]}) ->
   io_lib:format("Invalid type specification for function ~w:~w/~w."
 		" The success typing is ~s\n", [M, F, A, Sig]);
diff --git a/lib/dialyzer/src/dialyzer.hrl b/lib/dialyzer/src/dialyzer.hrl
index aa3f703af2..9d2e554981 100644
--- a/lib/dialyzer/src/dialyzer.hrl
+++ b/lib/dialyzer/src/dialyzer.hrl
@@ -52,10 +52,11 @@
 -define(WARN_CONTRACT_NOT_EQUAL, warn_contract_not_equal).
 -define(WARN_CONTRACT_SUBTYPE, warn_contract_subtype).
 -define(WARN_CONTRACT_SUPERTYPE, warn_contract_supertype).
+-define(WARN_CONTRACT_RANGE, warn_contract_range).
 -define(WARN_CALLGRAPH, warn_callgraph).
 -define(WARN_UNMATCHED_RETURN, warn_umatched_return).
 -define(WARN_RACE_CONDITION, warn_race_condition).
--define(WARN_BEHAVIOUR,warn_behaviour).
+-define(WARN_BEHAVIOUR, warn_behaviour).
 
 %%
 %% The following type has double role:
@@ -70,7 +71,7 @@
                        | ?WARN_CONTRACT_NOT_EQUAL | ?WARN_CONTRACT_SUBTYPE
                        | ?WARN_CONTRACT_SUPERTYPE | ?WARN_CALLGRAPH
                        | ?WARN_UNMATCHED_RETURN | ?WARN_RACE_CONDITION
-                       | ?WARN_BEHAVIOUR.
+                       | ?WARN_BEHAVIOUR | ?WARN_CONTRACT_RANGE.
 
 %%
 %% This is the representation of each warning as they will be returned
diff --git a/lib/dialyzer/src/dialyzer_cl_parse.erl b/lib/dialyzer/src/dialyzer_cl_parse.erl
index b68d6d190e..690ad7b8d3 100644
--- a/lib/dialyzer/src/dialyzer_cl_parse.erl
+++ b/lib/dialyzer/src/dialyzer_cl_parse.erl
@@ -20,10 +20,8 @@
 
 -module(dialyzer_cl_parse).
 
-%% Avoid warning for local function error/1 clashing with autoimported BIF.
--compile({no_auto_import,[error/1]}).
 -export([start/0, get_lib_dir/1]).
--export([collect_args/1]).	% used also by typer_options.erl
+-export([collect_args/1]).	% used also by typer
 
 -include("dialyzer.hrl").
 
@@ -32,9 +30,11 @@
 -type dial_cl_parse_ret() :: {'check_init', #options{}}
                            | {'plt_info', #options{}}
                            | {'cl', #options{}}
-                           | {{'gui', 'gs' | 'wx'}, #options{}} 
+                           | {{'gui', 'gs' | 'wx'}, #options{}}
                            | {'error', string()}.
 
+-type deep_string() :: string() | [deep_string()].
+
 %%-----------------------------------------------------------------------
 
 -spec start() -> dial_cl_parse_ret().
@@ -82,7 +82,7 @@ cl(["--get_warnings"|T]) ->
   put(dialyzer_options_get_warnings, true),
   cl(T);
 cl(["-D"|_]) ->
-  error("No defines specified after -D");
+  cl_error("No defines specified after -D");
 cl(["-D"++Define|T]) ->
   Def = re:split(Define, "=", [{return, list}]),
   append_defines(Def),
@@ -92,7 +92,7 @@ cl(["-h"|_]) ->
 cl(["--help"|_]) ->
   help_message();
 cl(["-I"]) ->
-  error("no include directory specified after -I");
+  cl_error("no include directory specified after -I");
 cl(["-I", Dir|T]) ->
   append_include(Dir),
   cl(T);
@@ -113,14 +113,14 @@ cl(["--com"++_|T]) ->
   NewTail = command_line(T),
   cl(NewTail);
 cl(["--output"]) ->
-  error("No outfile specified");
+  cl_error("No outfile specified");
 cl(["-o"]) ->
-  error("No outfile specified");
+  cl_error("No outfile specified");
 cl(["--output",Output|T]) ->
   put(dialyzer_output, Output),
   cl(T);
 cl(["--output_plt"]) ->
-  error("No outfile specified for --output_plt");
+  cl_error("No outfile specified for --output_plt");
 cl(["--output_plt",Output|T]) ->
   put(dialyzer_output_plt, Output),
   cl(T);
@@ -139,7 +139,7 @@ cl(["--fullpath"|T]) ->
 cl(["-pa", Path|T]) ->
   case code:add_patha(Path) of
     true -> cl(T);
-    {error, _} -> error("Bad directory for -pa: "++Path)
+    {error, _} -> cl_error("Bad directory for -pa: " ++ Path)
   end;
 cl(["--plt"]) ->
   error("No plt specified for --plt");
@@ -174,14 +174,14 @@ cl(["--verbose"|T]) ->
   put(dialyzer_options_report_mode, verbose),
   cl(T);
 cl(["-W"|_]) ->
-  error("-W given without warning");
+  cl_error("-W given without warning");
 cl(["-Whelp"|_]) ->
   help_warnings();
 cl(["-W"++Warn|T]) ->
   append_var(dialyzer_warnings, [list_to_atom(Warn)]),
   cl(T);
 cl(["--dump_callgraph"]) ->
-  error("No outfile specified for --dump_callgraph");
+  cl_error("No outfile specified for --dump_callgraph");
 cl(["--dump_callgraph", File|T]) ->
   put(dialyzer_callgraph_file, File),
   cl(T);
@@ -197,7 +197,7 @@ cl([H|_] = L) ->
       NewTail = command_line(L),
       cl(NewTail);
     false ->
-      error("Unknown option: " ++ H)
+      cl_error("Unknown option: " ++ H)
   end;
 cl([]) ->
   {RetTag, Opts} =
@@ -216,7 +216,7 @@ cl([]) ->
 	end
     end,
   case dialyzer_options:build(Opts) of
-    {error, Msg} -> error(Msg);
+    {error, Msg} -> cl_error(Msg);
     OptsRecord -> {RetTag, OptsRecord}
   end.
 
@@ -232,7 +232,9 @@ command_line(T0) ->
   end,
   T.
 
-error(Str) ->
+-spec cl_error(deep_string()) -> no_return().
+
+cl_error(Str) ->
   Msg = lists:flatten(Str),
   throw({dialyzer_cl_parse_error, Msg}).
 
@@ -330,11 +332,15 @@ get_plts([], Acc) -> {lists:reverse(Acc), []}.
 
 %%-----------------------------------------------------------------------
 
+-spec help_warnings() -> no_return().
+
 help_warnings() ->
   S = warning_options_msg(),
   io:put_chars(S),
   erlang:halt(?RET_NOTHING_SUSPICIOUS).
 
+-spec help_message() -> no_return().
+
 help_message() ->
   S = "Usage: dialyzer [--help] [--version] [--shell] [--quiet] [--verbose]
 		[-pa dir]* [--plt plt] [--plts plt*] [-Ddefine]*
@@ -494,13 +500,13 @@ warning_options_msg() ->
      Include warnings about behaviour callbacks which drift from the published
      recommended interfaces.
   -Wunderspecs ***
-     Warn about underspecified functions 
+     Warn about underspecified functions
      (those whose -spec is strictly more allowing than the success typing).
 
 The following options are also available but their use is not recommended:
 (they are mostly for Dialyzer developers and internal debugging)
   -Woverspecs ***
-     Warn about overspecified functions 
+     Warn about overspecified functions
      (those whose -spec is strictly less allowing than the success typing).
   -Wspecdiffs ***
      Warn when the -spec is different than the success typing.
diff --git a/lib/dialyzer/src/dialyzer_dataflow.erl b/lib/dialyzer/src/dialyzer_dataflow.erl
index 2ffbcd3e82..7137dbc036 100644
--- a/lib/dialyzer/src/dialyzer_dataflow.erl
+++ b/lib/dialyzer/src/dialyzer_dataflow.erl
@@ -2,7 +2,7 @@
 %%--------------------------------------------------------------------
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2006-2010. All Rights Reserved.
+%% Copyright Ericsson AB 2006-2011. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -657,7 +657,8 @@ handle_apply_or_call([{TypeOfApply, {Fun, Sig, Contr, LocalRet}}|Left],
       true  -> opaque;
       false -> structured
     end,
-  RetWithoutLocal = t_inf(t_inf(ContrRet, BifRet, RetMode), SigRange, RetMode),
+  RetWithoutContr = t_inf(SigRange, BifRet, RetMode),
+  RetWithoutLocal = t_inf(ContrRet, RetWithoutContr, RetMode),
   ?debug("--------------------------------------------------------\n", []),
   ?debug("Fun: ~p\n", [Fun]),
   ?debug("Args: ~s\n", [erl_types:t_to_string(t_product(ArgTypes))]),
@@ -666,6 +667,7 @@ handle_apply_or_call([{TypeOfApply, {Fun, Sig, Contr, LocalRet}}|Left],
 	 [erl_types:t_to_string(t_product(NewArgsContract))]),
   ?debug("NewArgsBif: ~s\n", [erl_types:t_to_string(t_product(NewArgsBif))]),
   ?debug("NewArgTypes: ~s\n", [erl_types:t_to_string(t_product(NewArgTypes))]),
+  ?debug("RetWithoutContr: ~s\n",[erl_types:t_to_string(RetWithoutContr)]),
   ?debug("RetWithoutLocal: ~s\n", [erl_types:t_to_string(RetWithoutLocal)]),
   ?debug("BifRet: ~s\n", [erl_types:t_to_string(BifRange(NewArgTypes))]),
   ?debug("ContrRet: ~s\n", [erl_types:t_to_string(CRange(TmpArgTypes))]),
@@ -700,22 +702,39 @@ handle_apply_or_call([{TypeOfApply, {Fun, Sig, Contr, LocalRet}}|Left],
   State2 =
     case FailedConj andalso not (IsFailBif orelse IsFailSig) of
       true ->
-	FailedSig = any_none(NewArgsSig),
-	FailedContract = any_none([CRange(TmpArgsContract)|NewArgsContract]),
-	FailedBif = any_none([BifRange(NewArgsBif)|NewArgsBif]),
-	InfSig = t_inf(t_fun(SigArgs, SigRange),
-		       t_fun(BifArgs, BifRange(BifArgs))),
-	FailReason = apply_fail_reason(FailedSig, FailedBif, FailedContract),
-        Msg = get_apply_fail_msg(Fun, Args, ArgTypes, NewArgTypes, InfSig,
-				 Contr, CArgs, State1, FailReason),
-	WarnType = case Msg of
-		     {call, _} -> ?WARN_FAILING_CALL;
-		     {apply, _} -> ?WARN_FAILING_CALL;
-		     {call_with_opaque, _} -> ?WARN_OPAQUE;
-		     {call_without_opaque, _} -> ?WARN_OPAQUE;
-		     {opaque_type_test, _} -> ?WARN_OPAQUE
-		   end,
-	state__add_warning(State1, WarnType, Tree, Msg);
+	case t_is_none(RetWithoutLocal) andalso
+	  not t_is_none(RetWithoutContr) andalso
+	  not any_none(NewArgTypes) of
+	  true ->
+	    {value, C1} = Contr,
+	    Contract = dialyzer_contracts:contract_to_string(C1),
+	    {M1, F1, A1} = state__lookup_name(Fun, State),
+	    ArgStrings = format_args(Args, ArgTypes, State),
+	    CRet = erl_types:t_to_string(RetWithoutContr),
+	    %% This Msg will be post_processed by dialyzer_succ_typings
+	    Msg =
+	      {contract_range, [Contract, M1, F1, A1, ArgStrings, CRet]},
+	    state__add_warning(State1, ?WARN_CONTRACT_RANGE, Tree, Msg);
+	  false ->
+	    FailedSig = any_none(NewArgsSig),
+	    FailedContract =
+	      any_none([CRange(TmpArgsContract)|NewArgsContract]),
+	    FailedBif = any_none([BifRange(NewArgsBif)|NewArgsBif]),
+	    InfSig = t_inf(t_fun(SigArgs, SigRange),
+			   t_fun(BifArgs, BifRange(BifArgs))),
+	    FailReason =
+	      apply_fail_reason(FailedSig, FailedBif, FailedContract),
+	    Msg = get_apply_fail_msg(Fun, Args, ArgTypes, NewArgTypes, InfSig,
+				     Contr, CArgs, State1, FailReason),
+	    WarnType = case Msg of
+			 {call, _} -> ?WARN_FAILING_CALL;
+			 {apply, _} -> ?WARN_FAILING_CALL;
+			 {call_with_opaque, _} -> ?WARN_OPAQUE;
+			 {call_without_opaque, _} -> ?WARN_OPAQUE;
+			 {opaque_type_test, _} -> ?WARN_OPAQUE
+		       end,
+	    state__add_warning(State1, WarnType, Tree, Msg)
+	end;
       false -> State1
     end,
   State3 =
@@ -1350,7 +1369,7 @@ do_clause(C, Arg, ArgType0, OrigArgType, Map,
 	bind_pat_vars(Pats, ArgTypes, [], Map1, State1)
     end,
   case BindRes of
-    {error, BindOrOpaque, NewPats, Type, OpaqueTerm} ->
+    {error, ErrorType, NewPats, Type, OpaqueTerm} ->
       ?debug("Failed binding pattern: ~s\nto ~s\n",
 	     [cerl_prettypr:format(C), format_type(ArgType0, State1)]),
       case state__warning_mode(State1) of
@@ -1358,8 +1377,9 @@ do_clause(C, Arg, ArgType0, OrigArgType, Map,
           {State1, Map, t_none(), ArgType0};
 	true ->
 	  PatString =
-	    case BindOrOpaque of
+	    case ErrorType of
 	      bind   -> format_patterns(Pats);
+	      record -> format_patterns(Pats);
 	      opaque -> format_patterns(NewPats)
 	    end,
 	  {Msg, Force} =
@@ -1399,13 +1419,15 @@ do_clause(C, Arg, ArgType0, OrigArgType, Map,
 		    false ->
 		      true
 		  end,
-		PatTypes = case BindOrOpaque of
+		PatTypes = case ErrorType of
 			     bind -> [PatString, format_type(ArgType0, State1)];
+			     record -> [PatString, format_type(Type, State1)];
 			     opaque -> [PatString, format_type(Type, State1),
 					format_type(OpaqueTerm, State1)]
-			      end,
-		FailedMsg = case BindOrOpaque of
+			   end,
+		FailedMsg = case ErrorType of
 			      bind  -> {pattern_match, PatTypes};
+			      record -> {record_match, PatTypes};
 			      opaque -> {opaque_match, PatTypes}
 			    end,
 		{FailedMsg, Force0}
@@ -1413,6 +1435,7 @@ do_clause(C, Arg, ArgType0, OrigArgType, Map,
 	  WarnType = case Msg of
 		       {opaque_match, _} -> ?WARN_OPAQUE;
 		       {pattern_match, _} -> ?WARN_MATCHING;
+		       {record_match, _} -> ?WARN_MATCHING;
 		       {pattern_match_cov, _} -> ?WARN_MATCHING
 		     end,
           {state__add_warning(State1, WarnType, C, Msg, Force),
@@ -1506,14 +1529,18 @@ bind_pat_vars(Pats, Types, Acc, Map, State) ->
   try
     bind_pat_vars(Pats, Types, Acc, Map, State, false)
   catch
-    throw:Error -> Error % Error = {error, bind | opaque, ErrorPats, ErrorType}
+    throw:Error -> 
+      %% Error = {error, bind | opaque | record, ErrorPats, ErrorType}
+      Error 
   end.
 
 bind_pat_vars_reverse(Pats, Types, Acc, Map, State) ->
   try
     bind_pat_vars(Pats, Types, Acc, Map, State, true)
   catch
-    throw:Error -> Error % Error = {error, bind | opaque, ErrorPats, ErrorType}
+    throw:Error -> 
+      %% Error = {error, bind | opaque | record, ErrorPats, ErrorType}
+      Error
   end.
 
 bind_pat_vars([Pat|PatLeft], [Type|TypeLeft], Acc, Map, State, Rev) ->
@@ -1568,18 +1595,21 @@ bind_pat_vars([Pat|PatLeft], [Type|TypeLeft], Acc, Map, State, Rev) ->
 	end;
       tuple ->
 	Es = cerl:tuple_es(Pat),
-	Prototype =
+	{TypedRecord, Prototype} =
 	  case Es of
-	    [] -> t_tuple([]);
+	    [] -> {false, t_tuple([])};
 	    [Tag|Left] ->
 	      case cerl:is_c_atom(Tag) of
 		true ->
 		  TagAtom = cerl:atom_val(Tag),
 		  case state__lookup_record(TagAtom, length(Left), State) of
-		    error -> t_tuple(length(Es));
-		    {ok, Record} -> Record
+		    error -> {false, t_tuple(length(Es))};
+		    {ok, Record} ->
+		      [_Head|AnyTail] = [t_any() || _ <- Es],
+		      UntypedRecord = t_tuple([t_atom(TagAtom)|AnyTail]),
+		      {not erl_types:t_is_equal(Record, UntypedRecord), Record}
 		  end;
-		false -> t_tuple(length(Es))
+		false -> {false, t_tuple(length(Es))}
 	      end
 	  end,
 	Tuple = t_inf(Prototype, Type),
@@ -1604,7 +1634,11 @@ bind_pat_vars([Pat|PatLeft], [Type|TypeLeft], Acc, Map, State, Rev) ->
 		bind_error([Pat], Tuple, Opaque, opaque);
 	      false ->
 		case [M || {M, _} <- Results, M =/= error] of
-		  [] -> bind_error([Pat], Tuple, t_none(), bind);
+		  [] ->
+		    case TypedRecord of
+		      true -> bind_error([Pat], Tuple, Prototype, record);
+		      false -> bind_error([Pat], Tuple, t_none(), bind)
+		    end;
 		  Maps ->
 		    Map1 = join_maps(Maps, Map),
 		    TupleType = t_sup([t_tuple(EsTypes)
@@ -2087,7 +2121,10 @@ handle_guard_eq(Guard, Map, Env, Eval, State) ->
 	true ->
 	  if
 	    Eval =:= pos -> {Map, t_atom(true)};
-	    Eval =:= neg -> throw({fail, none});
+	    Eval =:= neg ->
+	      ArgTypes = [t_from_term(cerl:concrete(Arg1)),
+			  t_from_term(cerl:concrete(Arg2))],
+	      signal_guard_fail(Eval, Guard, ArgTypes, State);
 	    Eval =:= dont_know -> {Map, t_atom(true)}
 	  end;
 	false ->
@@ -2142,7 +2179,10 @@ handle_guard_eqeq(Guard, Map, Env, Eval, State) ->
     {literal, literal} ->
       case cerl:concrete(Arg1) =:= cerl:concrete(Arg2) of
 	true ->
-	  if Eval =:= neg -> throw({fail, none});
+	  if Eval =:= neg ->
+	      ArgTypes = [t_from_term(cerl:concrete(Arg1)),
+			  t_from_term(cerl:concrete(Arg2))],
+	      signal_guard_fail(Eval, Guard, ArgTypes, State);
 	     Eval =:= pos -> {Map, t_atom(true)};
 	     Eval =:= dont_know -> {Map, t_atom(true)}
 	  end;
@@ -2217,7 +2257,7 @@ bind_eqeq_guard_lit_other(Guard, Arg1, Arg2, Map, Env, State) ->
 	true -> {Map1, t_atom(true)};
 	false ->
 	  {_, Type0} = bind_guard(Arg2, Map, Env, Eval, State),
-	  signal_guard_fail(Eval, Guard, [Type0, t_atom(true)], State)
+	  signal_guard_fail(Eval, Guard, [Type0, t_atom(false)], State)
       end;
     Term ->
       LitType = t_from_term(Term),
@@ -2238,11 +2278,11 @@ handle_guard_and(Guard, Map, Env, Eval, State) ->
     pos ->
       {Map1, Type1} = bind_guard(Arg1, Map, Env, Eval, State),
       case t_is_atom(true, Type1) of
-	false -> throw({fail, none});
+	false -> signal_guard_fail(Eval, Guard, [Type1, t_any()], State);
 	true ->
 	  {Map2, Type2} = bind_guard(Arg2, Map1, Env, Eval, State),
 	  case t_is_atom(true, Type2) of
-	    false -> throw({fail, none});
+	    false -> signal_guard_fail(Eval, Guard, [Type1, Type2], State);
 	    true -> {Map2, t_atom(true)}
 	  end
       end;
@@ -2257,7 +2297,7 @@ handle_guard_and(Guard, Map, Env, Eval, State) ->
 	end,
       case t_is_atom(false, Type1) orelse t_is_atom(false, Type2) of
 	true -> {join_maps([Map1, Map2], Map), t_atom(false)};
-	false -> throw({fail, none})
+	false -> signal_guard_fail(Eval, Guard, [Type1, Type2], State)
       end;
     dont_know ->
       {Map1, Type1} = bind_guard(Arg1, Map, Env, dont_know, State),
@@ -2297,16 +2337,16 @@ handle_guard_or(Guard, Map, Env, Eval, State) ->
 	    orelse
 	    (t_is_atom(true, Bool2) andalso t_is_boolean(Bool1))) of
 	true -> {join_maps([Map1, Map2], Map), t_atom(true)};
-	false -> throw({fail, none})
+	false -> signal_guard_fail(Eval, Guard, [Bool1, Bool2], State)
       end;
     neg ->
       {Map1, Type1} = bind_guard(Arg1, Map, Env, neg, State),
       case t_is_atom(false, Type1) of
-	false -> throw({fail, none});
+	false -> signal_guard_fail(Eval, Guard, [Type1, t_any()], State);
 	true ->
 	  {Map2, Type2} = bind_guard(Arg2, Map1, Env, neg, State),
 	  case t_is_atom(false, Type2) of
-	    false -> throw({fail, none});
+	    false -> signal_guard_fail(Eval, Guard, [Type1, Type2], State);
 	    true -> {Map2, t_atom(false)}
 	  end
       end;
@@ -2337,13 +2377,17 @@ handle_guard_not(Guard, Map, Env, Eval, State) ->
       {Map1, Type} = bind_guard(Arg, Map, Env, pos, State),
       case t_is_atom(true, Type) of
 	true -> {Map1, t_atom(false)};
-	false -> throw({fail, none})
+	false ->
+	  {_, Type0} = bind_guard(Arg, Map, Env, Eval, State),
+	  signal_guard_fail(Eval, Guard, [Type0], State)
       end;
     pos ->
       {Map1, Type} = bind_guard(Arg, Map, Env, neg, State),
       case t_is_atom(false, Type) of
 	true -> {Map1, t_atom(true)};
-	false -> throw({fail, none})
+	false ->
+	  {_, Type0} = bind_guard(Arg, Map, Env, Eval, State),
+	  signal_guard_fail(Eval, Guard, [Type0], State)
       end;
     dont_know ->
       {Map1, Type} = bind_guard(Arg, Map, Env, dont_know, State),
@@ -2382,9 +2426,15 @@ signal_guard_fail(Eval, Guard, ArgTypes, State) ->
       true ->
 	[ArgType1, ArgType2] = ArgTypes,
 	[Arg1, Arg2] = Args,
-	{guard_fail, [format_args_1([Arg1], [ArgType1], State),
-		      atom_to_list(F),
-		      format_args_1([Arg2], [ArgType2], State)]};
+	Kind = 
+	  case Eval of
+	    neg -> neg_guard_fail;
+	    pos -> guard_fail;
+	    dont_know -> guard_fail
+	  end,
+	{Kind, [format_args_1([Arg1], [ArgType1], State),
+		atom_to_list(F),
+		format_args_1([Arg2], [ArgType2], State)]};
       false ->
 	mk_guard_msg(Eval, F, Args, ArgTypes, State)
     end,
@@ -2767,8 +2817,6 @@ state__new(Callgraph, Tree, Plt, Module, Records, BehaviourTranslations) ->
   FunTab = init_fun_tab(Funs, dict:new(), TreeMap, Callgraph, Plt, Opaques),
   Work = init_work([get_label(Tree)]),
   Env = dict:store(top, map__new(), dict:new()),
-  Opaques = erl_types:module_builtin_opaques(Module) ++
-    erl_types:t_opaque_from_records(Records),
   #state{callgraph = Callgraph, envs = Env, fun_tab = FunTab, opaques = Opaques,
 	 plt = Plt, races = dialyzer_races:new(), records = Records,
 	 warning_mode = false, warnings = [], work = Work, tree_map = TreeMap,
diff --git a/lib/dialyzer/src/dialyzer_options.erl b/lib/dialyzer/src/dialyzer_options.erl
index 29e164628a..b2a67de8bd 100644
--- a/lib/dialyzer/src/dialyzer_options.erl
+++ b/lib/dialyzer/src/dialyzer_options.erl
@@ -47,6 +47,7 @@ build(Opts) ->
 		  ?WARN_FAILING_CALL,
 		  ?WARN_BIN_CONSTRUCTION,
 		  ?WARN_CALLGRAPH,
+		  ?WARN_CONTRACT_RANGE,
 		  ?WARN_CONTRACT_TYPES,
 		  ?WARN_CONTRACT_SYNTAX],
   DefaultWarns1 = ordsets:from_list(DefaultWarns),
diff --git a/lib/dialyzer/src/dialyzer_plt.erl b/lib/dialyzer/src/dialyzer_plt.erl
index a7ba270c41..807c9af44f 100644
--- a/lib/dialyzer/src/dialyzer_plt.erl
+++ b/lib/dialyzer/src/dialyzer_plt.erl
@@ -28,8 +28,6 @@
 %%%-------------------------------------------------------------------
 -module(dialyzer_plt).
 
-%% Avoid warning for local function error/1 clashing with autoimported BIF.
--compile({no_auto_import,[error/1]}).
 -export([check_plt/3,
 	 compute_md5_from_files/1,
 	 contains_mfa/2,
@@ -56,8 +54,7 @@
 	 plt_and_info_from_file/1,
 	 get_specs/1,
 	 get_specs/4,
-	 to_file/4
-	]).
+	 to_file/4]).
 
 %% Debug utilities
 -export([pp_non_returning/0, pp_mod/1]).
@@ -68,6 +65,8 @@
 
 -type mod_deps() :: dict().
 
+-type deep_string() :: string() | [deep_string()].
+
 %% The following are used for searching the PLT when using the GUI
 %% (e.g. in show or search PLT contents). The user might be searching
 %% with a partial specification, in which case the missing items
@@ -203,8 +202,8 @@ get_default_plt() ->
     false ->
       case os:getenv("HOME") of
 	false ->
-	  error("The HOME environment variable needs to be set " ++
-		"so that Dialyzer knows where to find the default PLT");
+	  plt_error("The HOME environment variable needs to be set " ++
+		    "so that Dialyzer knows where to find the default PLT");
 	HomeDir -> filename:join(HomeDir, ".dialyzer_plt")
       end;
     UserSpecPlt -> UserSpecPlt
@@ -226,7 +225,7 @@ from_file(FileName, ReturnInfo) ->
       case check_version(Rec) of
 	error ->
 	  Msg = io_lib:format("Old PLT file ~s\n", [FileName]),
-	  error(Msg);
+	  plt_error(Msg);
 	ok ->
 	  Plt = #plt{info = Rec#file_plt.info,
 		     types = Rec#file_plt.types,
@@ -241,8 +240,9 @@ from_file(FileName, ReturnInfo) ->
 	  end
       end;
     {error, Reason} ->
-      error(io_lib:format("Could not read PLT file ~s: ~p\n",
-			  [FileName, Reason]))
+      Msg = io_lib:format("Could not read PLT file ~s: ~p\n",
+			  [FileName, Reason]),
+      plt_error(Msg)
   end.
 
 -type err_rsn() :: 'not_valid' | 'no_such_file' | 'read_error'.
@@ -518,7 +518,9 @@ expand_args([ArgType|Left]) ->
    end ++
    ","|expand_args(Left)].
 
-error(Msg) ->
+-spec plt_error(deep_string()) -> no_return().
+
+plt_error(Msg) ->
   throw({dialyzer_error, lists:flatten(Msg)}).
 
 %%---------------------------------------------------------------------------
diff --git a/lib/dialyzer/src/dialyzer_succ_typings.erl b/lib/dialyzer/src/dialyzer_succ_typings.erl
index 8bfc66fc39..daf68d24f0 100644
--- a/lib/dialyzer/src/dialyzer_succ_typings.erl
+++ b/lib/dialyzer/src/dialyzer_succ_typings.erl
@@ -131,8 +131,9 @@ get_warnings_from_modules([M|Ms], State, DocPlt,
   %% Check if there are contracts for functions that do not exist
   Warnings1 = 
     dialyzer_contracts:contracts_without_fun(Contracts, AllFuns, Callgraph),
-  {Warnings2, FunTypes, RaceCode, PublicTables, NamedTables} =
+  {RawWarnings2, FunTypes, RaceCode, PublicTables, NamedTables} =
     dialyzer_dataflow:get_warnings(ModCode, Plt, Callgraph, Records, NoWarnUnused),
+  {NewAcc, Warnings2} = postprocess_dataflow_warns(RawWarnings2, State, Acc),
   Attrs = cerl:module_attrs(ModCode),
   Warnings3 = if BehavioursChk ->
 		  dialyzer_behaviours:check_callbacks(M, Attrs,
@@ -145,10 +146,31 @@ get_warnings_from_modules([M|Ms], State, DocPlt,
                                        NamedTables),
   State1 = st__renew_state_calls(NewCallgraph, State),
   get_warnings_from_modules(Ms, State1, NewDocPlt, BehavioursChk,
-			    [Warnings1, Warnings2, Warnings3|Acc]);
+			    [Warnings1, Warnings2, Warnings3|NewAcc]);
 get_warnings_from_modules([], #st{plt = Plt}, DocPlt, _, Acc) ->
   {lists:flatten(Acc), Plt, DocPlt}.
 
+postprocess_dataflow_warns(RawWarnings, State, WarnAcc) ->
+  postprocess_dataflow_warns(RawWarnings, State, WarnAcc, []).
+
+postprocess_dataflow_warns([], _State, WAcc, Acc) ->
+  {WAcc, lists:reverse(Acc)};
+postprocess_dataflow_warns([{?WARN_CONTRACT_RANGE, {File, CallL}, Msg}|Rest],
+			   #st{codeserver = Codeserver} = State, WAcc, Acc) ->
+  {contract_range, [Contract, M, F, A, ArgStrings, CRet]} = Msg,
+  {ok, {{File, _ContrL} = FileLine, _C}} =
+    dialyzer_codeserver:lookup_mfa_contract({M,F,A}, Codeserver),
+  NewMsg =
+    {contract_range, [Contract, M, F, ArgStrings, CallL, CRet]},
+  W = {?WARN_CONTRACT_RANGE, FileLine, NewMsg},
+  Filter =
+    fun({?WARN_CONTRACT_TYPES, FL, _}) when FL =:= FileLine -> false;
+       (_) -> true
+    end,
+  postprocess_dataflow_warns(Rest, State, lists:filter(Filter, WAcc), [W|Acc]);
+postprocess_dataflow_warns([W|Rest], State, Wacc, Acc) ->
+  postprocess_dataflow_warns(Rest, State, Wacc, [W|Acc]).
+  
 refine_succ_typings(ModulePostorder, State) ->
   ?debug("Module postorder: ~p\n", [ModulePostorder]),
   refine_succ_typings(ModulePostorder, State, []).
diff --git a/lib/dialyzer/src/dialyzer_utils.erl b/lib/dialyzer/src/dialyzer_utils.erl
index 248fdf6835..12f8dec67e 100644
--- a/lib/dialyzer/src/dialyzer_utils.erl
+++ b/lib/dialyzer/src/dialyzer_utils.erl
@@ -2,7 +2,7 @@
 %%-----------------------------------------------------------------------
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2006-2010. All Rights Reserved.
+%% Copyright Ericsson AB 2006-2011. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -214,14 +214,13 @@ get_record_and_type_info([], _Module, Records, RecDict) ->
       ?debug(_NewRecDict),
       Ok;
     {error, Name, Error} ->
-      {error, lists:flatten(io_lib:format("  Error while parsing #~w{}: ~s\n",
-					  [Name, Error]))}
+      {error, flat_format("  Error while parsing #~w{}: ~s\n", [Name, Error])}
   end.
 
 add_new_type(TypeOrOpaque, Name, TypeForm, ArgForms, Module, RecDict) ->
   case erl_types:type_is_defined(TypeOrOpaque, Name, RecDict) of
     true ->
-      throw({error, io_lib:format("Type already defined: ~w\n", [Name])});
+      throw({error, flat_format("Type ~s already defined\n", [Name])});
     false ->
       ArgTypes = [erl_types:t_from_form(X) || X <- ArgForms],
       case lists:all(fun erl_types:t_is_var/1, ArgTypes) of
@@ -229,8 +228,8 @@ add_new_type(TypeOrOpaque, Name, TypeForm, ArgForms, Module, RecDict) ->
 	  ArgNames = [erl_types:t_var_name(X) || X <- ArgTypes],
 	  dict:store({TypeOrOpaque, Name}, {Module, TypeForm, ArgNames}, RecDict);
 	false ->
-	  throw({error, io_lib:format("Type declaration for ~w does not "
-				      "have variables as parameters", [Name])})
+	  throw({error, flat_format("Type declaration for ~w does not "
+				    "have variables as parameters", [Name])})
       end
   end.
 
@@ -338,14 +337,14 @@ get_spec_info([{attribute, Ln, spec, {Id, TypeSpec}}|Left],
       get_spec_info(Left, NewSpecDict, RecordsDict, ModName, File);
     {ok, {{OtherFile, L},_C}} ->
       {Mod, Fun, Arity} = MFA,
-      Msg = io_lib:format("  Contract for function ~w:~w/~w "
-			  "already defined in ~s:~w\n",
-			  [Mod, Fun, Arity, OtherFile, L]),
+      Msg = flat_format("  Contract for function ~w:~w/~w "
+			"already defined in ~s:~w\n",
+			[Mod, Fun, Arity, OtherFile, L]),
       throw({error, Msg})
   catch
     throw:{error, Error} ->
-      {error, lists:flatten(io_lib:format("  Error while parsing contract "
-					  "in line ~w: ~s\n", [Ln, Error]))}
+      {error, flat_format("  Error while parsing contract in line ~w: ~s\n",
+			  [Ln, Error])}
   end;
 get_spec_info([{attribute, _, file, {IncludeFile, _}}|Left],
 	      SpecDict, RecordsDict, ModName, _File) ->
@@ -419,6 +418,9 @@ format_sig(Type, RecDict) ->
   ")" ++ RevSig = lists:reverse(Sig),
   lists:reverse(RevSig).
 
+flat_format(Fmt, Lst) ->
+  lists:flatten(io_lib:format(Fmt, Lst)).
+
 %%-------------------------------------------------------------------
 %% Author      : Per Gustafsson <[email protected]>
 %% Description : Provides better printing of binaries.
diff --git a/lib/dialyzer/vsn.mk b/lib/dialyzer/vsn.mk
index b2902e95ed..53b6f8c553 100644
--- a/lib/dialyzer/vsn.mk
+++ b/lib/dialyzer/vsn.mk
@@ -1 +1 @@
-DIALYZER_VSN = 2.4.0
+DIALYZER_VSN = 2.4.2