Merge branch 'sa/dialyzer-behaviours'

* sa/dialyzer-behaviours:
  Wrap up behaviours patch for Dialyzer
  Detection of callback-spec discrepancies
  Allow none() as return value in callbacks
  Behaviour callback discrepancy detection for Dialyzer
  Add lookup function for callbacks
  Store callbacks in codeserver and PLT
  Collect callback definitions during compilation
  Update inets results

OTP-9731

12 files changed, 387 insertions, 358 deletions

diff --git a/lib/dialyzer/src/dialyzer.erl b/lib/dialyzer/src/dialyzer.erl
index 5014a4244c..3e3c12405f 100644
--- a/lib/dialyzer/src/dialyzer.erl
+++ b/lib/dialyzer/src/dialyzer.erl
@@ -442,23 +442,29 @@ message_to_string({opaque_type_test, [Fun, Opaque]}) ->
 message_to_string({race_condition, [M, F, Args, Reason]}) ->
   io_lib:format("The call ~w:~w~s ~s\n", [M, F, Args, Reason]);
 %%----- Warnings for behaviour errors --------------------
-message_to_string({callback_type_mismatch, [B, F, A, O]}) ->
-  io_lib:format("The inferred return type of the ~w/~w callback includes the"
-		" type ~s which is not a valid return for the ~w behaviour\n",
-		[F, A, erl_types:t_to_string(O), B]);
-message_to_string({callback_arg_type_mismatch, [B, F, A, N, O]}) ->
-  io_lib:format("The inferred type of the ~s argument of ~w/~w callback"
-		" includes the type ~s which is not valid for the ~w behaviour"
-		"\n", [ordinal(N), F, A, erl_types:t_to_string(O), B]);
+message_to_string({callback_type_mismatch, [B, F, A, ST, CT]}) ->
+  io_lib:format("The inferred return type of ~w/~w (~s) has nothing in common"
+		" with ~s, which is the expected return type for the callback of"
+		" ~w behaviour\n", [F, A, ST, CT, B]);
+message_to_string({callback_arg_type_mismatch, [B, F, A, N, ST, CT]}) ->
+  io_lib:format("The inferred type for the ~s argument of ~w/~w (~s) is"
+		" not a supertype of ~s, which is expected type for this"
+		" argument in the callback of the ~w behaviour\n",
+		[ordinal(N), F, A, ST, CT, B]);
+message_to_string({callback_spec_type_mismatch, [B, F, A, ST, CT]}) ->
+  io_lib:format("The return type ~s in the specification of ~w/~w is not a"
+		" subtype of ~s, which is the expected return type for the"
+		" callback of ~w behaviour\n", [ST, F, A, CT, B]);
+message_to_string({callback_spec_arg_type_mismatch, [B, F, A, N, ST, CT]}) ->
+  io_lib:format("The specified type for the ~s argument of ~w/~w (~s) is"
+		" not a supertype of ~s, which is expected type for this"
+		" argument in the callback of the ~w behaviour\n",
+		[ordinal(N), F, A, ST, CT, B]);
 message_to_string({callback_missing, [B, F, A]}) ->
   io_lib:format("Undefined callback function ~w/~w (behaviour '~w')\n",
 		[F, A, B]);
-message_to_string({invalid_spec, [B, F, A, R]}) ->
-  io_lib:format("The spec for the ~w:~w/~w callback is not correct: ~s\n",
-		[B, F, A, R]);
-message_to_string({spec_missing, [B, F, A]}) ->
-  io_lib:format("Type info about ~w:~w/~w callback is not available\n",
-		[B, F, A]).
+message_to_string({callback_info_missing, [B]}) ->
+  io_lib:format("Callback info about the ~w behaviour is not available\n", [B]).
 
 %%-----------------------------------------------------------------------------
 %% Auxiliary functions below
diff --git a/lib/dialyzer/src/dialyzer.hrl b/lib/dialyzer/src/dialyzer.hrl
index 9d2e554981..5e089d1773 100644
--- a/lib/dialyzer/src/dialyzer.hrl
+++ b/lib/dialyzer/src/dialyzer.hrl
@@ -57,6 +57,7 @@
 -define(WARN_UNMATCHED_RETURN, warn_umatched_return).
 -define(WARN_RACE_CONDITION, warn_race_condition).
 -define(WARN_BEHAVIOUR, warn_behaviour).
+-define(WARN_UNDEFINED_CALLBACK, warn_undefined_callbacks).
 
 %%
 %% The following type has double role:
@@ -71,7 +72,8 @@
                        | ?WARN_CONTRACT_NOT_EQUAL | ?WARN_CONTRACT_SUBTYPE
                        | ?WARN_CONTRACT_SUPERTYPE | ?WARN_CALLGRAPH
                        | ?WARN_UNMATCHED_RETURN | ?WARN_RACE_CONDITION
-                       | ?WARN_BEHAVIOUR | ?WARN_CONTRACT_RANGE.
+                       | ?WARN_BEHAVIOUR | ?WARN_CONTRACT_RANGE
+		       | ?WARN_UNDEFINED_CALLBACK.
 
 %%
 %% This is the representation of each warning as they will be returned
diff --git a/lib/dialyzer/src/dialyzer_analysis_callgraph.erl b/lib/dialyzer/src/dialyzer_analysis_callgraph.erl
index abad1f3a75..62153fa176 100644
--- a/lib/dialyzer/src/dialyzer_analysis_callgraph.erl
+++ b/lib/dialyzer/src/dialyzer_analysis_callgraph.erl
@@ -43,8 +43,7 @@
 	  parent                        :: pid(),
 	  plt                           :: dialyzer_plt:plt(),
 	  start_from     = byte_code    :: start_from(),
-	  use_contracts  = true         :: boolean(),
-	  behaviours     = {false,[]}   :: {boolean(),[atom()]}
+	  use_contracts  = true         :: boolean()
 	 }).
 
 -record(server_state, {parent :: pid(), legal_warnings :: [dial_warn_tag()]}).
@@ -57,9 +56,7 @@
 
 start(Parent, LegalWarnings, Analysis) ->
   RacesOn = ordsets:is_element(?WARN_RACE_CONDITION, LegalWarnings),
-  BehavOn = ordsets:is_element(?WARN_BEHAVIOUR, LegalWarnings),
-  Analysis0 = Analysis#analysis{race_detection = RacesOn,
-				behaviours_chk = BehavOn},
+  Analysis0 = Analysis#analysis{race_detection = RacesOn},
   Analysis1 = expand_files(Analysis0),
   Analysis2 = run_analysis(Analysis1),
   State = #server_state{parent = Parent, legal_warnings = LegalWarnings},
@@ -125,8 +122,7 @@ analysis_start(Parent, Analysis) ->
 			  plt = Plt,
 			  parent = Parent,
 			  start_from = Analysis#analysis.start_from,
-			  use_contracts = Analysis#analysis.use_contracts,
-			  behaviours = {Analysis#analysis.behaviours_chk, []}
+			  use_contracts = Analysis#analysis.use_contracts
 			 },
   Files = ordsets:from_list(Analysis#analysis.files),
   {Callgraph, NoWarn, TmpCServer0} = compile_and_store(Files, State),
@@ -180,8 +176,8 @@ analysis_start(Parent, Analysis) ->
   send_analysis_done(Parent, Plt4, State3#analysis_state.doc_plt).
 
 analyze_callgraph(Callgraph, State) ->
-  Plt = State#analysis_state.plt,
   Codeserver = State#analysis_state.codeserver,
+  Plt = dialyzer_plt:insert_callbacks(State#analysis_state.plt, Codeserver),
   Parent = State#analysis_state.parent,
   case State#analysis_state.analysis_type of
     plt_build ->
@@ -192,13 +188,11 @@ analyze_callgraph(Callgraph, State) ->
       State#analysis_state{plt = NewPlt};
     succ_typings ->
       NoWarn = State#analysis_state.no_warn_unused,
-      {BehavioursChk, _Known} = State#analysis_state.behaviours,
       DocPlt = State#analysis_state.doc_plt,
       Callgraph1 = dialyzer_callgraph:finalize(Callgraph),
       {Warnings, NewPlt, NewDocPlt} = 
 	dialyzer_succ_typings:get_warnings(Callgraph1, Plt, DocPlt,
-					   Codeserver, NoWarn, Parent,
-					   BehavioursChk),
+					   Codeserver, NoWarn, Parent),
       dialyzer_callgraph:delete(Callgraph1),
       send_warnings(State#analysis_state.parent, Warnings),
       State#analysis_state{plt = NewPlt, doc_plt = NewDocPlt}
@@ -213,8 +207,7 @@ compile_and_store(Files, #analysis_state{codeserver = CServer,
 					 include_dirs = Dirs,
 					 parent = Parent,
 					 use_contracts = UseContracts,
-					 start_from = StartFrom,
-					 behaviours = {BehChk, _}
+					 start_from = StartFrom
 					} = State) ->
   send_log(Parent, "Reading files and computing callgraph... "),
   {T1, _} = statistics(runtime),
@@ -263,37 +256,26 @@ compile_and_store(Files, #analysis_state{codeserver = CServer,
   {T2, _} = statistics(runtime),
   Msg1 = io_lib:format("done in ~.2f secs\nRemoving edges... ", [(T2-T1)/1000]),
   send_log(Parent, Msg1),
-  {KnownBehaviours, UnknownBehaviours} =
-    dialyzer_behaviours:get_behaviours(Modules, NewCServer),
-  if UnknownBehaviours =:= [] -> ok;
-     true -> send_unknown_behaviours(Parent, UnknownBehaviours)
-  end,
-  State1 = State#analysis_state{behaviours = {BehChk, KnownBehaviours}},
-  NewCallgraph2 = cleanup_callgraph(State1, NewCServer, NewCallgraph1, Modules),
+  NewCallgraph2 = cleanup_callgraph(State, NewCServer, NewCallgraph1, Modules),
   {T3, _} = statistics(runtime),
   Msg2 = io_lib:format("done in ~.2f secs\n", [(T3-T2)/1000]),
   send_log(Parent, Msg2),
   {NewCallgraph2, sets:from_list(NoWarn), NewCServer}.
 
 cleanup_callgraph(#analysis_state{plt = InitPlt, parent = Parent,
-				  codeserver = CodeServer,
-				  behaviours = {BehChk, KnownBehaviours}
+				  codeserver = CodeServer
 				 },
 		  CServer, Callgraph, Modules) ->
   ModuleDeps = dialyzer_callgraph:module_deps(Callgraph),
   send_mod_deps(Parent, ModuleDeps),
   {Callgraph1, ExtCalls} = dialyzer_callgraph:remove_external(Callgraph),
-  if BehChk ->
-      RelevantAPICalls =
-	dialyzer_behaviours:get_behaviour_apis(KnownBehaviours),
-      BehaviourAPICalls = [Call || {_From, To} = Call <- ExtCalls,
-				   lists:member(To, RelevantAPICalls)],
-      Callgraph2 =
-	dialyzer_callgraph:put_behaviour_api_calls(BehaviourAPICalls,
-						   Callgraph1);
-     true ->
-      Callgraph2 = Callgraph1
-  end,
+  RelevantAPICalls =
+    dialyzer_behaviours:get_behaviour_apis([gen_server]),
+  BehaviourAPICalls = [Call || {_From, To} = Call <- ExtCalls,
+			       lists:member(To, RelevantAPICalls)],
+  Callgraph2 =
+    dialyzer_callgraph:put_behaviour_api_calls(BehaviourAPICalls,
+					       Callgraph1),
   ExtCalls1 = [Call || Call = {_From, To} <- ExtCalls,
 		       not dialyzer_plt:contains_mfa(InitPlt, To)],
   {BadCalls1, RealExtCalls} =
@@ -325,63 +307,42 @@ compile_src(File, Includes, Defines, Callgraph, CServer, UseContracts) ->
   case dialyzer_utils:get_abstract_code_from_src(File, CompOpts) of
     {error, _Msg} = Error -> Error;
     {ok, AbstrCode} ->
-      case dialyzer_utils:get_core_from_abstract_code(AbstrCode, CompOpts) of
-	error -> {error, "  Could not find abstract code for: " ++ File};
-	{ok, Core} ->
-          Mod = cerl:concrete(cerl:module_name(Core)),
-	  NoWarn = abs_get_nowarn(AbstrCode, Mod),
-	  case dialyzer_utils:get_record_and_type_info(AbstrCode) of
-	    {error, _} = Error -> Error;
-	    {ok, RecInfo} ->
-	      CServer2 =
-		dialyzer_codeserver:store_temp_records(Mod, RecInfo, CServer),
-	      case UseContracts of
-		true ->
-		  case dialyzer_utils:get_spec_info(Mod, AbstrCode, RecInfo) of
-		    {error, _} = Error -> Error;
-		    {ok, SpecInfo} ->
-		      CServer3 =
-			dialyzer_codeserver:store_temp_contracts(Mod,
-								 SpecInfo,
-								 CServer2),
-		      store_core(Mod, Core, NoWarn, Callgraph, CServer3)
-		  end;
-		false ->
-		  store_core(Mod, Core, NoWarn, Callgraph, CServer2)
-	      end
-	  end
-      end
+      compile_common(File, AbstrCode, CompOpts, Callgraph, CServer, UseContracts)
   end.
 
 compile_byte(File, Callgraph, CServer, UseContracts) ->
   case dialyzer_utils:get_abstract_code_from_beam(File) of
     error ->
       {error, "  Could not get abstract code for: " ++ File ++ "\n" ++
-       "  Recompile with +debug_info or analyze starting from source code"};
+	 "  Recompile with +debug_info or analyze starting from source code"};
     {ok, AbstrCode} ->
-      case dialyzer_utils:get_core_from_abstract_code(AbstrCode) of
-	error -> {error, "  Could not get core for: "++File};
-	{ok, Core} ->
-          Mod = cerl:concrete(cerl:module_name(Core)),
-          NoWarn = abs_get_nowarn(AbstrCode, Mod),
-	  case dialyzer_utils:get_record_and_type_info(AbstrCode) of
-	    {error, _} = Error -> Error;
-	    {ok, RecInfo} ->
-	      CServer1 =
-		dialyzer_codeserver:store_temp_records(Mod, RecInfo, CServer),
-	      case UseContracts of
-		true ->
-		  case dialyzer_utils:get_spec_info(Mod, AbstrCode, RecInfo) of
-		    {error, _} = Error -> Error;
-		    {ok, SpecInfo} ->
-		      CServer2 =
-			dialyzer_codeserver:store_temp_contracts(Mod, SpecInfo,
-								 CServer1),
-		      store_core(Mod, Core, NoWarn, Callgraph, CServer2)
-		  end;
-		false ->
-		  store_core(Mod, Core, NoWarn, Callgraph, CServer1)
-	      end
+      compile_common(File, AbstrCode, [], Callgraph, CServer, UseContracts)
+  end.
+
+compile_common(File, AbstrCode, CompOpts, Callgraph, CServer, UseContracts) ->
+  case dialyzer_utils:get_core_from_abstract_code(AbstrCode, CompOpts) of
+    error -> {error, "  Could not get core Erlang code for: " ++ File};
+    {ok, Core} ->
+      Mod = cerl:concrete(cerl:module_name(Core)),
+      NoWarn = abs_get_nowarn(AbstrCode, Mod),
+      case dialyzer_utils:get_record_and_type_info(AbstrCode) of
+	{error, _} = Error -> Error;
+	{ok, RecInfo} ->
+	  CServer1 =
+	    dialyzer_codeserver:store_temp_records(Mod, RecInfo, CServer),
+	  case UseContracts of
+	    true ->
+	      case dialyzer_utils:get_spec_info(Mod, AbstrCode, RecInfo) of
+		{error, _} = Error -> Error;
+		{ok, SpecInfo, CallbackInfo} ->
+		  CServer2 =
+		    dialyzer_codeserver:store_temp_contracts(Mod, SpecInfo,
+							     CallbackInfo,
+							     CServer1),
+		  store_core(Mod, Core, NoWarn, Callgraph, CServer2)
+	      end;
+	    false ->
+	      store_core(Mod, Core, NoWarn, Callgraph, CServer1)
 	  end
       end
   end.
diff --git a/lib/dialyzer/src/dialyzer_behaviours.erl b/lib/dialyzer/src/dialyzer_behaviours.erl
index 47ce9ba6eb..56eb46d78a 100644
--- a/lib/dialyzer/src/dialyzer_behaviours.erl
+++ b/lib/dialyzer/src/dialyzer_behaviours.erl
@@ -30,7 +30,7 @@
 
 -module(dialyzer_behaviours).
 
--export([check_callbacks/4, get_behaviours/2, get_behaviour_apis/1,
+-export([check_callbacks/4, get_behaviour_apis/1,
 	 translate_behaviour_api_call/5, translatable_behaviours/1,
 	 translate_callgraph/3]).
 
@@ -51,12 +51,6 @@
 
 %%--------------------------------------------------------------------
 
--spec get_behaviours([module()], dialyzer_codeserver:codeserver()) ->
-  {[behaviour()], [behaviour()]}.
-
-get_behaviours(Modules, Codeserver) ->
-  get_behaviours(Modules, Codeserver, [], []).
-
 -spec check_callbacks(module(), [{cerl:cerl(), cerl:cerl()}],
 		      dialyzer_plt:plt(),
 		      dialyzer_codeserver:codeserver()) -> [dial_warning()].
@@ -69,12 +63,165 @@ check_callbacks(Module, Attrs, Plt, Codeserver) ->
       MFA = {Module,module_info,0},
       {_Var,Code} = dialyzer_codeserver:lookup_mfa_code(MFA, Codeserver),
       File = get_file(cerl:get_ann(Code)),
-      State = #state{plt = Plt, codeserver = Codeserver, filename = File,
-		     behlines = BehLines},
+      State = #state{plt = Plt, filename = File, behlines = BehLines,
+		     codeserver = Codeserver},
       Warnings = get_warnings(Module, Behaviours, State),
       [add_tag_file_line(Module, W, State) || W <- Warnings]
   end.
 
+%%--------------------------------------------------------------------
+
+get_behaviours(Attrs) ->
+  BehaviourListsAndLine = [{cerl:concrete(L2), hd(cerl:get_ann(L2))} ||
+		  {L1, L2} <- Attrs, cerl:is_literal(L1),
+		  cerl:is_literal(L2), cerl:concrete(L1) =:= 'behaviour'],
+  Behaviours = lists:append([Behs || {Behs,_} <- BehaviourListsAndLine]),
+  BehLines = [{B,L} || {L1,L} <- BehaviourListsAndLine, B <- L1],
+  {Behaviours, BehLines}.
+
+get_warnings(Module, Behaviours, State) ->
+  get_warnings(Module, Behaviours, State, []).
+
+get_warnings(_, [], _, Acc) ->
+  Acc;
+get_warnings(Module, [Behaviour|Rest], State, Acc) ->
+  NewAcc = check_behaviour(Module, Behaviour, State, Acc),
+  get_warnings(Module, Rest, State, NewAcc).
+
+check_behaviour(Module, Behaviour, #state{plt = Plt} = State, Acc) ->
+  case dialyzer_plt:lookup_callbacks(Plt, Behaviour) of
+    [] -> [{callback_info_missing, [Behaviour]}|Acc];
+    Callbacks -> check_all_callbacks(Module, Behaviour, Callbacks, State, Acc)
+  end.
+
+check_all_callbacks(_Module, _Behaviour, [], _State, Acc) ->
+  Acc;
+check_all_callbacks(Module, Behaviour, [Cb|Rest],
+		    #state{plt = Plt, codeserver = Codeserver} = State, Acc) ->
+  {{Behaviour, Function, Arity},
+   {{_BehFile, _BehLine}, Callback}} = Cb,
+  CbMFA = {Module, Function, Arity},
+  CbReturnType = dialyzer_contracts:get_contract_return(Callback),
+  CbArgTypes = dialyzer_contracts:get_contract_args(Callback),
+  Records =
+    case dict:find(Module, dialyzer_codeserver:get_records(Codeserver)) of
+      {ok, V} -> V;
+      error -> dict:new()
+    end,
+  Acc0 = Acc,
+  Acc1 = 
+    case dialyzer_plt:lookup(Plt, CbMFA) of
+      'none' -> [{callback_missing, [Behaviour, Function, Arity]}|Acc0];
+      {'value', RetArgTypes} ->
+	Acc00 = Acc0,
+	{ReturnType, ArgTypes} = RetArgTypes,
+	Acc01 =
+	  case erl_types:t_is_subtype(ReturnType, CbReturnType) of
+	    true -> Acc00;
+	    false ->
+	      case erl_types:t_is_none(
+		     erl_types:t_inf(ReturnType, CbReturnType)) of
+		false -> Acc00;
+		true ->
+		  [{callback_type_mismatch,
+		    [Behaviour, Function, Arity,
+		     erl_types:t_to_string(ReturnType, Records),
+		     erl_types:t_to_string(CbReturnType, Records)]}|Acc00]
+	      end
+	  end,
+	Acc02 =
+	  case erl_types:any_none(
+		 erl_types:t_inf_lists(ArgTypes, CbArgTypes)) of
+	    false -> Acc01;
+	    true ->
+	      find_mismatching_args(type, ArgTypes, CbArgTypes, Behaviour,
+				    Function, Arity, Records, 1, Acc01)
+	  end,
+	Acc02
+    end,
+  Acc2 =
+    case dialyzer_codeserver:lookup_mfa_contract(CbMFA, Codeserver) of
+      'error' -> Acc1;
+      {ok, {{File, Line}, Contract}} ->
+	Acc10 = Acc1,
+	SpecReturnType = dialyzer_contracts:get_contract_return(Contract),
+	SpecArgTypes = dialyzer_contracts:get_contract_args(Contract),
+	Acc11 =
+	  case erl_types:t_is_subtype(SpecReturnType, CbReturnType) of
+	    true -> Acc10;
+	    false -> [{callback_spec_type_mismatch,
+		       [File, Line, Behaviour, Function, Arity,
+			erl_types:t_to_string(SpecReturnType, Records),
+			erl_types:t_to_string(CbReturnType, Records)]}|Acc10]
+	  end,
+	Acc12 =
+	  case erl_types:any_none(
+		 erl_types:t_inf_lists(SpecArgTypes, CbArgTypes)) of
+	    false -> Acc11;
+	    true ->
+	      find_mismatching_args({spec, File, Line}, SpecArgTypes,
+				    CbArgTypes, Behaviour, Function,
+				    Arity, Records, 1, Acc11)
+	  end,
+	Acc12
+    end,
+  NewAcc = Acc2,
+  check_all_callbacks(Module, Behaviour, Rest, State, NewAcc).
+
+find_mismatching_args(_, [], [], _Beh, _Function, _Arity, _Records, _N, Acc) ->
+  Acc;
+find_mismatching_args(Kind, [Type|Rest], [CbType|CbRest], Behaviour,
+		      Function, Arity, Records, N, Acc) ->
+  case erl_types:t_is_none(erl_types:t_inf(Type, CbType)) of
+    false ->
+      find_mismatching_args(Kind, Rest, CbRest, Behaviour, Function,
+			    Arity, Records, N+1, Acc);
+    true ->
+      Info =
+	[Behaviour, Function, Arity, N,
+	 erl_types:t_to_string(Type, Records),
+	 erl_types:t_to_string(CbType, Records)],
+      NewAcc =
+	[case Kind of
+	   type -> {callback_arg_type_mismatch, Info};
+	   {spec, File, Line} ->
+	     {callback_spec_arg_type_mismatch, [File, Line | Info]}
+	 end | Acc],
+      find_mismatching_args(Kind, Rest, CbRest, Behaviour, Function,
+			    Arity, Records, N+1, NewAcc)
+  end.
+
+add_tag_file_line(_Module, {Tag, [B|_R]} = Warn, State)
+  when Tag =:= callback_missing;
+       Tag =:= callback_info_missing ->
+  {B, Line} = lists:keyfind(B, 1, State#state.behlines),
+  Category =
+    case Tag of
+      callback_missing -> ?WARN_BEHAVIOUR;
+      callback_info_missing -> ?WARN_UNDEFINED_CALLBACK
+    end,
+  {Category, {State#state.filename, Line}, Warn};
+add_tag_file_line(_Module, {Tag, [File, Line|R]}, _State)
+  when Tag =:= callback_spec_type_mismatch;
+       Tag =:= callback_spec_arg_type_mismatch ->
+  {?WARN_BEHAVIOUR, {File, Line}, {Tag, R}};
+add_tag_file_line(Module, {_Tag, [_B, Fun, Arity|_R]} = Warn, State) ->
+  {_A, FunCode} =
+    dialyzer_codeserver:lookup_mfa_code({Module, Fun, Arity},
+					State#state.codeserver),
+  Anns = cerl:get_ann(FunCode),
+  FileLine = {get_file(Anns), get_line(Anns)},
+  {?WARN_BEHAVIOUR, FileLine, Warn}.
+
+get_line([Line|_]) when is_integer(Line) -> Line;
+get_line([_|Tail]) -> get_line(Tail);
+get_line([]) -> -1.
+
+get_file([{file, File}|_]) -> File;
+get_file([_|Tail]) -> get_file(Tail).
+
+%%-----------------------------------------------------------------------------
+
 -spec translatable_behaviours(cerl:c_module()) -> behaviour_api_dict().
 
 translatable_behaviours(Tree) ->
@@ -133,182 +280,6 @@ translate_callgraph([{Behaviour,_}|Behaviours], Module, Callgraph) ->
 translate_callgraph([], _Module, Callgraph) ->
   Callgraph.
 
-%%--------------------------------------------------------------------
-
-get_behaviours(Attrs) ->
-  BehaviourListsAndLine = [{cerl:concrete(L2), hd(cerl:get_ann(L2))} ||
-		  {L1, L2} <- Attrs, cerl:is_literal(L1),
-		  cerl:is_literal(L2), cerl:concrete(L1) =:= 'behaviour'],
-  Behaviours = lists:append([Behs || {Behs,_} <- BehaviourListsAndLine]),
-  BehLines = [{B,L} || {L1,L} <- BehaviourListsAndLine, B <- L1],
-  {Behaviours, BehLines}.
-
-get_warnings(Module, Behaviours, State) ->
-  get_warnings(Module, Behaviours, State, []).
-
-get_warnings(_, [], _, Acc) ->
-  Acc;
-get_warnings(Module, [Behaviour|Rest], State, Acc) ->
-  Warnings = check_behaviour(Module, Behaviour, State),
-  get_warnings(Module, Rest, State, Warnings ++ Acc).
-
-check_behaviour(Module, Behaviour, State) ->
-  try
-    Callbacks = Behaviour:behaviour_info(callbacks),
-    Fun = fun({_,_,_}) -> true;
-	     (_)       -> false
-	  end,
-    case lists:any(Fun, Callbacks) of
-      true ->  check_all_callbacks(Module, Behaviour, Callbacks, State);
-      false -> []
-    end
-  catch
-    _:_ -> []
-  end.
-
-check_all_callbacks(Module, Behaviour, Callbacks, State) ->
-  check_all_callbacks(Module, Behaviour, Callbacks, State, []).
-
-check_all_callbacks(_Module, _Behaviour, [], _State, Acc) ->
-  Acc;
-check_all_callbacks(Module, Behaviour, [{Fun, Arity, Spec}|Rest],
-                    #state{codeserver = CServer} = State, Acc) ->
-  Records = dialyzer_codeserver:get_records(CServer),
-  ExpTypes = dialyzer_codeserver:get_exported_types(CServer),
-  case parse_spec(Spec, ExpTypes, Records) of
-    {ok, Fun, Type} ->
-      RetType = erl_types:t_fun_range(Type),
-      ArgTypes = erl_types:t_fun_args(Type),
-      Warns = check_callback(Module, Behaviour, Fun, Arity, RetType,
-			     ArgTypes, State#state.plt);
-    Else ->
-      Warns = [{invalid_spec, [Behaviour, Fun, Arity, reason_spec_error(Else)]}]
-  end,
-  check_all_callbacks(Module, Behaviour, Rest, State, Warns ++ Acc);
-check_all_callbacks(Module, Behaviour, [{Fun, Arity}|Rest], State, Acc) ->
-  Warns = {spec_missing, [Behaviour, Fun, Arity]},
-  check_all_callbacks(Module, Behaviour, Rest, State, [Warns|Acc]).
-
-parse_spec(String, ExpTypes, Records) ->
-  case erl_scan:string(String) of
-    {ok, Tokens, _} ->
-      case erl_parse:parse(Tokens) of
-	{ok, Form} ->
-	  case Form of
-	    {attribute, _, 'spec', {{Fun, _}, [TypeForm|_Constraint]}} ->
-	      MaybeRemoteType = erl_types:t_from_form(TypeForm),
-	      try
-		Type = erl_types:t_solve_remote(MaybeRemoteType, ExpTypes,
-                                                Records),
-		{ok, Fun, Type}
-	      catch
-		throw:{error,Msg} -> {spec_remote_error, Msg}
-	      end;
-	    _Other -> not_a_spec
-	  end;
-	{error, {Line, _, Msg}} -> {spec_parser_error, Line, Msg}
-      end;
-    _Other ->
-      lexer_error
-  end.
-
-reason_spec_error({spec_remote_error, Msg}) ->
-  io_lib:format("Remote type solver error: ~s. Make sure the behaviour source is included in the analysis or the plt",[Msg]);
-reason_spec_error(not_a_spec) ->
-  "This is not a spec";
-reason_spec_error({spec_parser_error, Line, Msg}) ->
-  io_lib:format("~s line of the spec: ~s", [ordinal(Line),Msg]);
-reason_spec_error(lexer_error) ->
-  "Lexical error".
-
-ordinal(1) -> "1st";
-ordinal(2) -> "2nd";
-ordinal(3) -> "3rd";
-ordinal(N) when is_integer(N) -> io_lib:format("~wth",[N]).
-
-check_callback(Module, Behaviour, Fun, Arity, XRetType, XArgTypes, Plt) ->
-  LookupType = dialyzer_plt:lookup(Plt, {Module, Fun, Arity}),
-  case LookupType of
-    {value, {Type,Args}} ->
-      Warn1 = case unifiable(Type, XRetType) of
-		[] -> [];
-		Offenders ->
-		  [{callback_type_mismatch,
-		   [Behaviour, Fun, Arity, erl_types:t_sup(Offenders)]}]
-	      end,
-      ZipArgs = lists:zip3(lists:seq(1, Arity), Args, XArgTypes),
-      Warn2 = [{callback_arg_type_mismatch,
-		[Behaviour, Fun, Arity, N,
-		 erl_types:t_sup(Offenders)]} ||
-		{Offenders, N} <- [check_callback_1(V) || V <- ZipArgs],
-		Offenders =/= []],
-      Warn1 ++ Warn2;
-    _ -> [{callback_missing, [Behaviour, Fun, Arity]}]
-  end.
-
-check_callback_1({N, T1, T2}) ->
-  {unifiable(T1, T2), N}.
-
-unifiable(Type1, Type2) ->
-  List1 = erl_types:t_elements(Type1),
-  List2 = erl_types:t_elements(Type2),
-  [T || T <- List1,
-	lists:all(fun(T1) ->
-		      erl_types:t_is_none(erl_types:t_inf(T, T1, opaque))
-		  end, List2)].
-
-add_tag_file_line(_Module, {Tag, [B|_R]} = Warn, State)
-  when Tag =:= spec_missing;
-       Tag =:= invalid_spec;
-       Tag =:= callback_missing ->
-  {B, Line} = lists:keyfind(B, 1, State#state.behlines),
-  {?WARN_BEHAVIOUR, {State#state.filename, Line}, Warn};
-add_tag_file_line(Module, {_Tag, [_B, Fun, Arity|_R]} = Warn, State) ->
-  {_A, FunCode} =
-    dialyzer_codeserver:lookup_mfa_code({Module, Fun, Arity},
-					State#state.codeserver),
-  Anns = cerl:get_ann(FunCode),
-  FileLine = {get_file(Anns), get_line(Anns)},
-  {?WARN_BEHAVIOUR, FileLine, Warn}.
-
-get_line([Line|_]) when is_integer(Line) -> Line;
-get_line([_|Tail]) -> get_line(Tail);
-get_line([]) -> -1.
-
-get_file([{file, File}|_]) -> File;
-get_file([_|Tail]) -> get_file(Tail).
-
-%%-----------------------------------------------------------------------------
-
-get_behaviours([], _Codeserver, KnownAcc, UnknownAcc) ->
-  {KnownAcc, UnknownAcc};
-get_behaviours([M|Rest], Codeserver, KnownAcc, UnknownAcc) ->
-  Tree = dialyzer_codeserver:lookup_mod_code(M, Codeserver),
-  Attrs = cerl:module_attrs(Tree),
-  {Behaviours, _BehLines} = get_behaviours(Attrs),
-  {Known, Unknown} = call_behaviours(Behaviours),
-  get_behaviours(Rest, Codeserver, Known ++ KnownAcc, Unknown ++ UnknownAcc).
-
-call_behaviours(Behaviours) ->
-  call_behaviours(Behaviours, [], []).
-call_behaviours([], KnownAcc, UnknownAcc) ->
-  {lists:reverse(KnownAcc), lists:reverse(UnknownAcc)};
-call_behaviours([Behaviour|Rest], KnownAcc, UnknownAcc) ->
-  try
-    Callbacks = Behaviour:behaviour_info(callbacks),
-    Fun = fun({_,_,_}) -> true;
-	     (_)       -> false
-	  end,
-    case lists:any(Fun, Callbacks) of
-      false -> call_behaviours(Rest, KnownAcc, [Behaviour | UnknownAcc]);
-      true  -> call_behaviours(Rest, [Behaviour | KnownAcc], UnknownAcc)
-    end
-  catch
-    _:_ -> call_behaviours(Rest, KnownAcc, [Behaviour | UnknownAcc])
-  end.
-
-%------------------------------------------------------------------------------
-
 get_behaviour_apis([], Acc) ->
   Acc;
 get_behaviour_apis([Behaviour | Rest], Acc) ->
diff --git a/lib/dialyzer/src/dialyzer_cl.erl b/lib/dialyzer/src/dialyzer_cl.erl
index 8d61216b7a..e638e2fff2 100644
--- a/lib/dialyzer/src/dialyzer_cl.erl
+++ b/lib/dialyzer/src/dialyzer_cl.erl
@@ -754,15 +754,13 @@ print_unknown_behaviours(#cl_state{output = Output,
 	true -> io:nl(Output); %% Need to do a newline first
 	false -> ok
       end,
-      case Format of
-	formatted ->
-	  io:put_chars(Output, "Unknown behaviours (behaviour_info(callbacks)"
-		       " does not return any specs):\n"),
-	  do_print_unknown_behaviours(Output, Behaviours, "  ");
-	raw ->
-	  io:put_chars(Output, "%% Unknown behaviours:\n"),
-	  do_print_unknown_behaviours(Output, Behaviours, "%%  ")
-      end
+      {Prompt, Prefix} =
+	case Format of
+	  formatted -> {"Unknown behaviours:\n","  "};
+	  raw -> {"%% Unknown behaviours:\n","%%  "}
+	end,
+      io:put_chars(Output, Prompt),
+      do_print_unknown_behaviours(Output, Behaviours, Prefix)
   end.
 
 do_print_unknown_behaviours(Output, [B|T], Before) ->
diff --git a/lib/dialyzer/src/dialyzer_cl_parse.erl b/lib/dialyzer/src/dialyzer_cl_parse.erl
index f80eb81ac6..ff8fc39a5e 100644
--- a/lib/dialyzer/src/dialyzer_cl_parse.erl
+++ b/lib/dialyzer/src/dialyzer_cl_parse.erl
@@ -491,6 +491,12 @@ warning_options_msg() ->
      Suppress warnings for patterns that are unused or cannot match.
   -Wno_opaque
      Suppress warnings for violations of opaqueness of data types.
+  -Wno_behaviours
+     Suppress warnings about behaviour callbacks which drift from the published
+     recommended interfaces.
+  -Wno_undefined_callbacks
+     Suppress warnings about behaviours that have no -callback attributes for
+     their callbacks.
   -Wunmatched_returns ***
      Include warnings for function calls which ignore a structured return
      value or do not match against one of many possible return value(s).
@@ -498,9 +504,6 @@ warning_options_msg() ->
      Include warnings for functions that only return by means of an exception.
   -Wrace_conditions ***
      Include warnings for possible race conditions.
-  -Wbehaviours ***
-     Include warnings about behaviour callbacks which drift from the published
-     recommended interfaces.
   -Wunderspecs ***
      Warn about underspecified functions
      (those whose -spec is strictly more allowing than the success typing).
diff --git a/lib/dialyzer/src/dialyzer_codeserver.erl b/lib/dialyzer/src/dialyzer_codeserver.erl
index b2097f7e53..c34a9f0b7d 100644
--- a/lib/dialyzer/src/dialyzer_codeserver.erl
+++ b/lib/dialyzer/src/dialyzer_codeserver.erl
@@ -28,10 +28,11 @@
 -module(dialyzer_codeserver).
 
 -export([delete/1,
-	 finalize_contracts/2,
+	 finalize_contracts/3,
          finalize_exported_types/2,
 	 finalize_records/2,
 	 get_contracts/1,
+	 get_callbacks/1,
          get_exported_types/1,
 	 get_exports/1,
 	 get_records/1,
@@ -54,7 +55,7 @@
 	 store_records/3,
 	 store_temp_records/3,
 	 store_contracts/3,
-	 store_temp_contracts/3]).
+	 store_temp_contracts/4]).
 
 -export_type([codeserver/0]).
 
@@ -70,7 +71,10 @@
 		     records             = dict:new() :: dict(),
 		     temp_records        = dict:new() :: dict(),
 		     contracts           = dict:new() :: dict(),
-		     temp_contracts      = dict:new() :: dict()}).
+		     callbacks           = dict:new() :: dict(),
+		     temp_contracts      = dict:new() :: dict(),
+		     temp_callbacks      = dict:new() :: dict()
+		    }).
 
 -opaque codeserver() :: #codeserver{}.
 
@@ -227,24 +231,42 @@ lookup_mfa_contract({M,_F,_A} = MFA, #codeserver{contracts = ContDict}) ->
 get_contracts(#codeserver{contracts = ContDict}) ->
   ContDict.
 
--spec store_temp_contracts(atom(), dict(), codeserver()) -> codeserver().
+-spec get_callbacks(codeserver()) -> dict().
 
-store_temp_contracts(Mod, Dict, #codeserver{temp_contracts = C} = CS)
+get_callbacks(#codeserver{callbacks = CallbDict}) ->
+  CallbDict.
+
+-spec store_temp_contracts(atom(), dict(), dict(), codeserver()) ->
+	 codeserver().
+
+store_temp_contracts(Mod, SpecDict, CallbackDict,
+		     #codeserver{temp_contracts = Cn,
+				 temp_callbacks = Cb} = CS)
   when is_atom(Mod) ->
-  case dict:size(Dict) =:= 0 of
-    true -> CS;
-    false -> CS#codeserver{temp_contracts = dict:store(Mod, Dict, C)}
+  CS1 =
+    case dict:size(SpecDict) =:= 0 of
+      true -> CS;
+      false -> CS#codeserver{temp_contracts = dict:store(Mod, SpecDict, Cn)}
+    end,
+  case dict:size(CallbackDict) =:= 0 of
+    true -> CS1;
+    false -> CS1#codeserver{temp_callbacks = dict:store(Mod, CallbackDict, Cb)}
   end.
 
--spec get_temp_contracts(codeserver()) -> dict().
+-spec get_temp_contracts(codeserver()) -> {dict(), dict()}.
 
-get_temp_contracts(#codeserver{temp_contracts = TempContDict}) ->
-  TempContDict.
+get_temp_contracts(#codeserver{temp_contracts = TempContDict,
+			       temp_callbacks = TempCallDict}) ->
+  {TempContDict, TempCallDict}.
 
--spec finalize_contracts(dict(), codeserver()) -> codeserver().
+-spec finalize_contracts(dict(), dict(), codeserver()) -> codeserver().
 
-finalize_contracts(Dict, CS)  ->
-  CS#codeserver{contracts = Dict, temp_contracts = dict:new()}.
+finalize_contracts(CnDict, CbDict, CS)  ->
+  CS#codeserver{contracts = CnDict,
+		callbacks = CbDict,
+		temp_contracts = dict:new(),
+		temp_callbacks = dict:new()
+	       }.
 
 table__new() ->
   spawn_link(fun() -> table__loop(none, dict:new()) end).
diff --git a/lib/dialyzer/src/dialyzer_contracts.erl b/lib/dialyzer/src/dialyzer_contracts.erl
index 84b926a17a..3469d70a4d 100644
--- a/lib/dialyzer/src/dialyzer_contracts.erl
+++ b/lib/dialyzer/src/dialyzer_contracts.erl
@@ -141,7 +141,8 @@ sequence([H|T], Delimiter) -> H ++ Delimiter ++ sequence(T, Delimiter).
 	  dialyzer_codeserver:codeserver().
 
 process_contract_remote_types(CodeServer) ->
-  TmpContractDict = dialyzer_codeserver:get_temp_contracts(CodeServer),
+  {TmpContractDict, TmpCallbackDict} =
+    dialyzer_codeserver:get_temp_contracts(CodeServer),
   ExpTypes = dialyzer_codeserver:get_exported_types(CodeServer),
   RecordDict = dialyzer_codeserver:get_records(CodeServer),
   ContractFun =
@@ -155,7 +156,9 @@ process_contract_remote_types(CodeServer) ->
 	dict:map(ContractFun, ContractDict)
     end,
   NewContractDict = dict:map(ModuleFun, TmpContractDict),
-  dialyzer_codeserver:finalize_contracts(NewContractDict, CodeServer).
+  NewCallbackDict = dict:map(ModuleFun, TmpCallbackDict),
+  dialyzer_codeserver:finalize_contracts(NewContractDict, NewCallbackDict,
+					 CodeServer).
 
 -spec check_contracts([{mfa(), file_contract()}],
 		      dialyzer_callgraph:callgraph(), dict()) -> plt_contracts().
diff --git a/lib/dialyzer/src/dialyzer_options.erl b/lib/dialyzer/src/dialyzer_options.erl
index b2a67de8bd..866650a0b2 100644
--- a/lib/dialyzer/src/dialyzer_options.erl
+++ b/lib/dialyzer/src/dialyzer_options.erl
@@ -49,7 +49,9 @@ build(Opts) ->
 		  ?WARN_CALLGRAPH,
 		  ?WARN_CONTRACT_RANGE,
 		  ?WARN_CONTRACT_TYPES,
-		  ?WARN_CONTRACT_SYNTAX],
+		  ?WARN_CONTRACT_SYNTAX,
+		  ?WARN_BEHAVIOUR,
+		  ?WARN_UNDEFINED_CALLBACK],
   DefaultWarns1 = ordsets:from_list(DefaultWarns),
   InitPlt = dialyzer_plt:get_default_plt(),
   DefaultOpts = #options{},
@@ -275,14 +277,16 @@ build_warnings([Opt|Opts], Warnings) ->
       no_contracts ->
 	Warnings1 = ordsets:del_element(?WARN_CONTRACT_SYNTAX, Warnings),
 	ordsets:del_element(?WARN_CONTRACT_TYPES, Warnings1);
+      no_behaviours ->
+	ordsets:del_element(?WARN_BEHAVIOUR, Warnings);
+      no_undefined_callbacks ->
+	ordsets:del_element(?WARN_UNDEFINED_CALLBACK, Warnings);
       unmatched_returns ->
 	ordsets:add_element(?WARN_UNMATCHED_RETURN, Warnings);
       error_handling ->
 	ordsets:add_element(?WARN_RETURN_ONLY_EXIT, Warnings);
       race_conditions ->
 	ordsets:add_element(?WARN_RACE_CONDITION, Warnings);
-      behaviours ->
-	ordsets:add_element(?WARN_BEHAVIOUR, Warnings);
       specdiffs ->
 	S = ordsets:from_list([?WARN_CONTRACT_SUBTYPE, 
 			       ?WARN_CONTRACT_SUPERTYPE,
diff --git a/lib/dialyzer/src/dialyzer_plt.erl b/lib/dialyzer/src/dialyzer_plt.erl
index 6033d7f17c..206c43e4e2 100644
--- a/lib/dialyzer/src/dialyzer_plt.erl
+++ b/lib/dialyzer/src/dialyzer_plt.erl
@@ -43,10 +43,12 @@
 	 %% insert/3,
 	 insert_list/2,
 	 insert_contract_list/2,
+	 insert_callbacks/2,
 	 insert_types/2,
          insert_exported_types/2,
 	 lookup/2,
 	 lookup_contract/2,
+	 lookup_callbacks/2,
 	 lookup_module/2,
 	 merge_plts/1,
          merge_plts_or_report_conflicts/2,
@@ -79,6 +81,7 @@
 -record(plt, {info           = table_new() :: dict(),
 	      types          = table_new() :: dict(),
 	      contracts      = table_new() :: dict(),
+	      callbacks      = table_new() :: dict(),
               exported_types = sets:new()  :: set()}).
 -opaque plt() :: #plt{}.
 
@@ -91,6 +94,7 @@
 		   file_md5_list = []          :: [file_md5()],
 		   info = dict:new()           :: dict(),
 		   contracts = dict:new()      :: dict(),
+		   callbacks = dict:new()      :: dict(),
 		   types = dict:new()          :: dict(),
                    exported_types = sets:new() :: set(),
 		   mod_deps                    :: mod_deps(),
@@ -105,20 +109,26 @@ new() ->
 
 -spec delete_module(plt(), atom()) -> plt().
 
-delete_module(#plt{info = Info, types = Types, contracts = Contracts,
+delete_module(#plt{info = Info, types = Types,
+		   contracts = Contracts,
+		   callbacks = Callbacks,
                    exported_types = ExpTypes}, Mod) ->
   #plt{info = table_delete_module(Info, Mod),
        types = table_delete_module2(Types, Mod),
        contracts = table_delete_module(Contracts, Mod),
+       callbacks = table_delete_module(Callbacks, Mod),
        exported_types = table_delete_module1(ExpTypes, Mod)}.
 
 -spec delete_list(plt(), [mfa() | integer()]) -> plt().
 
-delete_list(#plt{info = Info, types = Types, contracts = Contracts,
+delete_list(#plt{info = Info, types = Types,
+		 contracts = Contracts,
+		 callbacks = Callbacks,
                  exported_types = ExpTypes}, List) ->
   #plt{info = table_delete_list(Info, List),
        types = Types,
        contracts = table_delete_list(Contracts, List),
+       callbacks = table_delete_list(Callbacks, List),
        exported_types = ExpTypes}.
 
 -spec insert_contract_list(plt(), dialyzer_contracts:plt_contracts()) -> plt().
@@ -126,16 +136,42 @@ delete_list(#plt{info = Info, types = Types, contracts = Contracts,
 insert_contract_list(#plt{contracts = Contracts} = PLT, List) ->
   PLT#plt{contracts = table_insert_list(Contracts, List)}.
 
+-spec insert_callbacks(plt(), dialyzer_codeserver:codeserver()) -> plt().
+
+insert_callbacks(#plt{callbacks = Callbacks} = Plt, Codeserver) ->
+  FunPreferNew = fun(_Key, _Val1, Val2) -> Val2 end,
+  FunDictMerger =
+    fun(_Key, Value, AccIn) -> dict:merge(FunPreferNew, Value, AccIn) end,
+  MergedCallbacks = dict:fold(FunDictMerger, dict:new(),
+			      dialyzer_codeserver:get_callbacks(Codeserver)),
+  List = dict:to_list(MergedCallbacks),
+  Plt#plt{callbacks = table_insert_list(Callbacks, List)}.
+
 -spec lookup_contract(plt(), mfa_patt()) -> 'none' | {'value', #contract{}}.
 
 lookup_contract(#plt{contracts = Contracts},
 		{M, F, _} = MFA) when is_atom(M), is_atom(F) ->
   table_lookup(Contracts, MFA).
 
+-spec lookup_callbacks(plt(), module()) -> [{mfa(),
+					     {{Filename::string(),
+					       Line::pos_integer()},
+					      #contract{}}}].
+
+lookup_callbacks(#plt{callbacks = Callbacks}, Mod) when is_atom(Mod) ->
+  FunModFilter =
+    fun({M, _F, _A}, _Val) -> M =:= Mod;
+       (       _Key, _Val) -> false
+    end,
+  ModCallbacks = dict:filter(FunModFilter, Callbacks),
+  dict:to_list(ModCallbacks).
+
 -spec delete_contract_list(plt(), [mfa()]) -> plt().
 
-delete_contract_list(#plt{contracts = Contracts} = PLT, List) ->
-  PLT#plt{contracts = table_delete_list(Contracts, List)}.
+delete_contract_list(#plt{contracts = Contracts,
+			  callbacks = Callbacks} = PLT, List) ->
+  PLT#plt{contracts = table_delete_list(Contracts, List),
+	  callbacks = table_delete_list(Callbacks, List)}.
 
 %% -spec insert(plt(), mfa() | integer(), {_, _}) -> plt().
 %%
@@ -230,6 +266,7 @@ from_file(FileName, ReturnInfo) ->
 	  Plt = #plt{info = Rec#file_plt.info,
 		     types = Rec#file_plt.types,
 		     contracts = Rec#file_plt.contracts,
+		     callbacks = Rec#file_plt.callbacks,
                      exported_types = Rec#file_plt.exported_types},
 	  case ReturnInfo of
 	    false -> Plt;
@@ -284,26 +321,34 @@ get_record_from_file(FileName) ->
 -spec merge_plts([plt()]) -> plt().
 
 merge_plts(List) ->
-  InfoList = [Info || #plt{info = Info} <- List],
-  TypesList = [Types || #plt{types = Types} <- List],
-  ExpTypesList = [ExpTypes || #plt{exported_types = ExpTypes} <- List],
-  ContractsList = [Contracts || #plt{contracts = Contracts} <- List],
+  {InfoList, TypesList, ExpTypesList, ContractsList, CallbacksList} =
+    group_fields(List),
   #plt{info = table_merge(InfoList),
        types = table_merge(TypesList),
        exported_types = sets_merge(ExpTypesList),
-       contracts = table_merge(ContractsList)}.
+       contracts = table_merge(ContractsList),
+       callbacks = table_merge(CallbacksList)
+      }.
 
 -spec merge_disj_plts([plt()]) -> plt().
 
 merge_disj_plts(List) ->
+  {InfoList, TypesList, ExpTypesList, ContractsList, CallbacksList} =
+    group_fields(List),
+  #plt{info = table_disj_merge(InfoList),
+       types = table_disj_merge(TypesList),
+       exported_types = sets_disj_merge(ExpTypesList),
+       contracts = table_disj_merge(ContractsList),
+       callbacks = table_disj_merge(CallbacksList)
+      }.
+
+group_fields(List) ->
   InfoList = [Info || #plt{info = Info} <- List],
   TypesList = [Types || #plt{types = Types} <- List],
   ExpTypesList = [ExpTypes || #plt{exported_types = ExpTypes} <- List],
   ContractsList = [Contracts || #plt{contracts = Contracts} <- List],
-  #plt{info = table_disj_merge(InfoList),
-       types = table_disj_merge(TypesList),
-       exported_types = sets_disj_merge(ExpTypesList),
-       contracts = table_disj_merge(ContractsList)}.
+  CallbacksList = [Callbacks || #plt{callbacks = Callbacks} <- List],
+  {InfoList, TypesList, ExpTypesList, ContractsList, CallbacksList}.
 
 -spec merge_plts_or_report_conflicts([file:filename()], [plt()]) -> plt().
 
@@ -329,7 +374,7 @@ find_duplicates(List) ->
 
 to_file(FileName,
 	#plt{info = Info, types = Types, contracts = Contracts,
-             exported_types = ExpTypes},
+	     callbacks = Callbacks, exported_types = ExpTypes},
 	ModDeps, {MD5, OldModDeps}) ->
   NewModDeps = dict:merge(fun(_Key, OldVal, NewVal) ->
 			      ordsets:union(OldVal, NewVal)
@@ -340,6 +385,7 @@ to_file(FileName,
 		     file_md5_list = MD5,
 		     info = Info,
 		     contracts = Contracts,
+		     callbacks = Callbacks,
 		     types = Types,
                      exported_types = ExpTypes,
 		     mod_deps = NewModDeps,
diff --git a/lib/dialyzer/src/dialyzer_succ_typings.erl b/lib/dialyzer/src/dialyzer_succ_typings.erl
index dc5a3fed37..4d86bb34a7 100644
--- a/lib/dialyzer/src/dialyzer_succ_typings.erl
+++ b/lib/dialyzer/src/dialyzer_succ_typings.erl
@@ -29,7 +29,7 @@
 
 -export([analyze_callgraph/3, 
 	 analyze_callgraph/4,
-	 get_warnings/7]).
+	 get_warnings/6]).
 
 %% These are only intended as debug functions.
 -export([doit/1,
@@ -106,21 +106,19 @@ get_refined_success_typings(State) ->
 -type doc_plt() :: 'undefined' | dialyzer_plt:plt().
 -spec get_warnings(dialyzer_callgraph:callgraph(), dialyzer_plt:plt(),
 		   doc_plt(), dialyzer_codeserver:codeserver(), set(),
-		   pid(), boolean()) ->
+		   pid()) ->
 	 {[dial_warning()], dialyzer_plt:plt(), doc_plt()}.
 
-get_warnings(Callgraph, Plt, DocPlt, Codeserver,
-	     NoWarnUnused, Parent, BehavioursChk) ->
+get_warnings(Callgraph, Plt, DocPlt, Codeserver, NoWarnUnused, Parent) ->
   InitState = #st{callgraph = Callgraph, codeserver = Codeserver,
 		  no_warn_unused = NoWarnUnused, parent = Parent, plt = Plt},
   NewState = get_refined_success_typings(InitState),
   Mods = dialyzer_callgraph:modules(NewState#st.callgraph),
   CWarns = dialyzer_contracts:get_invalid_contract_warnings(Mods, Codeserver,
 							    NewState#st.plt),
-  get_warnings_from_modules(Mods, NewState, DocPlt, BehavioursChk, CWarns).
+  get_warnings_from_modules(Mods, NewState, DocPlt, CWarns).
 
-get_warnings_from_modules([M|Ms], State, DocPlt,
-			  BehavioursChk, Acc) when is_atom(M) ->
+get_warnings_from_modules([M|Ms], State, DocPlt, Acc) when is_atom(M) ->
   send_log(State#st.parent, io_lib:format("Getting warnings for ~w\n", [M])),
   #st{callgraph = Callgraph, codeserver = Codeserver,
       no_warn_unused = NoWarnUnused, plt = Plt} = State,
@@ -135,19 +133,15 @@ get_warnings_from_modules([M|Ms], State, DocPlt,
     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,
-						      Plt, Codeserver);
-		 true -> []
-	      end,
+  Warnings3 = dialyzer_behaviours:check_callbacks(M, Attrs, Plt, Codeserver),
   NewDocPlt = insert_into_doc_plt(FunTypes, Callgraph, DocPlt),
   NewCallgraph =
     dialyzer_callgraph:renew_race_info(Callgraph, RaceCode, PublicTables,
                                        NamedTables),
   State1 = st__renew_state_calls(NewCallgraph, State),
-  get_warnings_from_modules(Ms, State1, NewDocPlt, BehavioursChk,
+  get_warnings_from_modules(Ms, State1, NewDocPlt,
 			    [Warnings1, Warnings2, Warnings3|NewAcc]);
-get_warnings_from_modules([], #st{plt = Plt}, DocPlt, _, Acc) ->
+get_warnings_from_modules([], #st{plt = Plt}, DocPlt, Acc) ->
   {lists:flatten(Acc), Plt, DocPlt}.
 
 postprocess_dataflow_warns(RawWarnings, State, WarnAcc) ->
@@ -476,7 +470,7 @@ doit(Module) ->
   {ok, Code} = dialyzer_utils:get_core_from_abstract_code(AbstrCode),
   {ok, Records} = dialyzer_utils:get_record_and_type_info(AbstrCode),
   %% contract typing info in dictionary format
-  {ok, Contracts} =
+  {ok, Contracts, _Callbacks} =
     dialyzer_utils:get_spec_info(cerl:concrete(cerl:module_name(Code)),
                                  AbstrCode, Records),
   Sigs0 = get_top_level_signatures(Code, Records, Contracts),
diff --git a/lib/dialyzer/src/dialyzer_utils.erl b/lib/dialyzer/src/dialyzer_utils.erl
index 12f8dec67e..2a248fb028 100644
--- a/lib/dialyzer/src/dialyzer_utils.erl
+++ b/lib/dialyzer/src/dialyzer_utils.erl
@@ -311,11 +311,15 @@ merge_records(NewRecords, OldRecords) ->
 %%
 %% ============================================================================
 
+-type spec_dict()     :: dict().
+-type callback_dict() :: dict().
+
 -spec get_spec_info(atom(), abstract_code(), dict()) ->
-        {'ok', dict()} | {'error', string()}.
+        {'ok', spec_dict(), callback_dict()} | {'error', string()}.
 
 get_spec_info(ModName, AbstractCode, RecordsDict) ->
-  get_spec_info(AbstractCode, dict:new(), RecordsDict, ModName, "nofile").
+  get_spec_info(AbstractCode, dict:new(), dict:new(),
+		RecordsDict, ModName, "nofile").
 
 %% TypeSpec is a list of conditional contracts for a function.
 %% Each contract is of the form {[Argument], Range, [Constraint]} where
@@ -323,21 +327,34 @@ get_spec_info(ModName, AbstractCode, RecordsDict) ->
 %%  - Constraint is of the form {subtype, T1, T2} where T1 and T2
 %%    are erl_types:erl_type()
 
-get_spec_info([{attribute, Ln, spec, {Id, TypeSpec}}|Left],
-	      SpecDict, RecordsDict, ModName, File) when is_list(TypeSpec) ->
+get_spec_info([{attribute, Ln, Contract, {Id, TypeSpec}}|Left],
+	      SpecDict, CallbackDict, RecordsDict, ModName, File)
+  when ((Contract =:= 'spec') or (Contract =:= 'callback')),
+       is_list(TypeSpec) ->
   MFA = case Id of
 	  {_, _, _} = T -> T;
 	  {F, A} -> {ModName, F, A}
 	end,
-  try dict:find(MFA, SpecDict) of
+  ActiveDict =
+    case Contract of
+      spec     -> SpecDict;
+      callback -> CallbackDict
+    end,
+  try dict:find(MFA, ActiveDict) of
     error ->
-      NewSpecDict =
+      NewActiveDict =
 	dialyzer_contracts:store_tmp_contract(MFA, {File, Ln}, TypeSpec,
-					      SpecDict, RecordsDict),
-      get_spec_info(Left, NewSpecDict, RecordsDict, ModName, File);
+					      ActiveDict, RecordsDict),
+      {NewSpecDict, NewCallbackDict} =
+	case Contract of
+	  spec     -> {NewActiveDict, CallbackDict};
+	  callback -> {SpecDict, NewActiveDict}
+	end,
+      get_spec_info(Left, NewSpecDict, NewCallbackDict,
+		    RecordsDict, ModName,File);
     {ok, {{OtherFile, L},_C}} ->
       {Mod, Fun, Arity} = MFA,
-      Msg = flat_format("  Contract for function ~w:~w/~w "
+      Msg = flat_format("  Contract/callback for function ~w:~w/~w "
 			"already defined in ~s:~w\n",
 			[Mod, Fun, Arity, OtherFile, L]),
       throw({error, Msg})
@@ -347,12 +364,14 @@ get_spec_info([{attribute, Ln, spec, {Id, TypeSpec}}|Left],
 			  [Ln, Error])}
   end;
 get_spec_info([{attribute, _, file, {IncludeFile, _}}|Left],
-	      SpecDict, RecordsDict, ModName, _File) ->
-  get_spec_info(Left, SpecDict, RecordsDict, ModName, IncludeFile);
-get_spec_info([_Other|Left], SpecDict, RecordsDict, ModName, File) ->
-  get_spec_info(Left, SpecDict, RecordsDict, ModName, File);
-get_spec_info([], SpecDict, _RecordsDict, _ModName, _File) ->
-  {ok, SpecDict}.
+	      SpecDict, CallbackDict, RecordsDict, ModName, _File) ->
+  get_spec_info(Left, SpecDict, CallbackDict,
+		RecordsDict, ModName, IncludeFile);
+get_spec_info([_Other|Left], SpecDict, CallbackDict,
+	      RecordsDict, ModName, File) ->
+  get_spec_info(Left, SpecDict, CallbackDict, RecordsDict, ModName, File);
+get_spec_info([], SpecDict, CallbackDict, _RecordsDict, _ModName, _File) ->
+  {ok, SpecDict, CallbackDict}.
 
 %% ============================================================================
 %%