Merge branch 'siri/unicode-merge' into maint

* siri/unicode-merge: (28 commits)
  stdlib: use 'unicode' option for regexp in ets
  ct: use 'unicode' option for regexps
  syntax_tools: add 'unicode' option to re:run for matching paths
  kernel: update simple error logger to print Unicode strings
  stdlib: add Unicode translation modifier in error_logger_tty_h
  wx: add Unicode translation modifier to wx_object
  stdlib: add Unicode translation modifier in debug format funs
  sasl: set encoding of SASL report log
  stdlib: use Unicode translation modifier in error_logger_file_h
  observer: Improve handling of Unicode
  mnesia: Improve handling of Unicode
  stdlib : Improve handling of Unicode
  kernel: Improve handling of Unicode
  hipe: Improve handling of Unicode
  edoc: Improve handling of Unicode
  syntax_tools: Improve handling of Unicode
  dialyzer: Improve handling of Unicode
  et: Improve handling of Unicode
  xref: Improve handling of Unicode
  fprof: Modify handling of Unicode
  eprof: Improve handling of Unicode
  eunit: Improve handling of Unicode
  stdlib: Improve handling of Unicode in escript
  stdlib: Improve handling of Unicode in edlin_expand
  stdlib: Modify handling of Unicode in proc_lib
  sasl: Improve handling of Unicode
  edoc: Improve handling of Unicode
  debugger: Improve handling of Unicode

OTP-14462
OTP-14464

22 files changed, 262 insertions, 206 deletions

diff --git a/lib/stdlib/src/dets.erl b/lib/stdlib/src/dets.erl
index 10e8c9c800..4e3fe0e5c1 100644
--- a/lib/stdlib/src/dets.erl
+++ b/lib/stdlib/src/dets.erl
@@ -1354,7 +1354,7 @@ open_file_loop2(Head, N) ->
                                   ?MODULE, [], Head);
         Message ->
             error_logger:format("** dets: unexpected message"
-                                "(ignored): ~w~n", [Message]),
+                                "(ignored): ~tw~n", [Message]),
             open_file_loop(Head, N)
     end.
 
@@ -1403,7 +1403,7 @@ apply_op(Op, From, Head, N) ->
 		    Head;
 		_Dirty when N =:= 0 -> % dirty or new_dirty
 		    %% The updates seems to have declined
-		    dets_utils:vformat("** dets: Auto save of ~p\n", 
+		    dets_utils:vformat("** dets: Auto save of ~tp\n",
                                        [Head#head.name]), 
 		    {NewHead, _Res} = perform_save(Head, true),
 		    erlang:garbage_collect(),
@@ -1587,13 +1587,13 @@ bug_found(Name, Op, Bad, From) ->
             %% If stream_op/5 found more requests, this is not
             %% the last operation.
             error_logger:format
-              ("** dets: Bug was found when accessing table ~w,~n"
-               "** dets: operation was ~p and reply was ~w.~n"
-               "** dets: Stacktrace: ~w~n",
+              ("** dets: Bug was found when accessing table ~tw,~n"
+               "** dets: operation was ~tp and reply was ~tw.~n"
+               "** dets: Stacktrace: ~tw~n",
                [Name, Op, Bad, erlang:get_stacktrace()]);
         false ->
             error_logger:format
-              ("** dets: Bug was found when accessing table ~w~n",
+              ("** dets: Bug was found when accessing table ~tw~n",
                [Name])
     end,
     if
@@ -2117,7 +2117,7 @@ do_open_file([Fname, Verbose], Parent, Server, Ref) ->
 	    Error;
 	Bad ->
 	    error_logger:format
-	      ("** dets: Bug was found in open_file/1, reply was ~w.~n", 
+	      ("** dets: Bug was found in open_file/1, reply was ~tw.~n",
 	       [Bad]),
 	    {error, {dets_bug, Fname, Bad}}
     end;
@@ -2135,7 +2135,7 @@ do_open_file([Tab, OpenArgs, Verb], Parent, Server, _Ref) ->
 	Bad ->
 	    error_logger:format
 	      ("** dets: Bug was found in open_file/2, arguments were~n"
-	       "** dets: ~w and reply was ~w.~n", 
+	       "** dets: ~tw and reply was ~tw.~n",
 	       [OpenArgs, Bad]),
 	    {error, {dets_bug, Tab, {open_file, OpenArgs}, Bad}}
     end.
@@ -3123,7 +3123,7 @@ check_safe_fixtable(Head) ->
          ((get(verbose) =:= yes) orelse dets_utils:debug_mode()) of
         true ->
             error_logger:format
-              ("** dets: traversal of ~p needs safe_fixtable~n",
+              ("** dets: traversal of ~tp needs safe_fixtable~n",
                [Head#head.name]);
         false ->
             ok
@@ -3189,7 +3189,7 @@ scan_read(H, From, _To, Min, _L, Ts, R, C) ->
 err(Error) ->
     case get(verbose) of
 	yes -> 
-	    error_logger:format("** dets: failed with ~w~n", [Error]),
+	    error_logger:format("** dets: failed with ~tw~n", [Error]),
 	    Error;
 	undefined  ->
 	    Error
diff --git a/lib/stdlib/src/dets_utils.erl b/lib/stdlib/src/dets_utils.erl
index da6ebd18f2..17f55ebdc2 100644
--- a/lib/stdlib/src/dets_utils.erl
+++ b/lib/stdlib/src/dets_utils.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 2001-2016. All Rights Reserved.
+%% Copyright Ericsson AB 2001-2017. All Rights Reserved.
 %% 
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -387,7 +387,7 @@ corrupt_reason(Head, Reason0) ->
 corrupt(Head, Error) ->
     case get(verbose) of
 	yes -> 
-	    error_logger:format("** dets: Corrupt table ~p: ~tp\n", 
+	    error_logger:format("** dets: Corrupt table ~tp: ~tp\n",
 				[Head#head.name, Error]);
 	_ -> ok
     end,
diff --git a/lib/stdlib/src/edlin_expand.erl b/lib/stdlib/src/edlin_expand.erl
index a1a97af4c5..bdcefda6e5 100644
--- a/lib/stdlib/src/edlin_expand.erl
+++ b/lib/stdlib/src/edlin_expand.erl
@@ -23,7 +23,7 @@
 
 -export([expand/1, format_matches/1]).
 
--import(lists, [reverse/1, nthtail/2, prefix/2]).
+-import(lists, [reverse/1, prefix/2]).
 
 %% expand(CurrentBefore) ->
 %%	{yes, Expansion, Matches} | {no, Matches}
@@ -75,15 +75,15 @@ to_atom(Str) ->
     end.
 
 match(Prefix, Alts, Extra0) ->
-    Len = length(Prefix),
+    Len = string:length(Prefix),
     Matches = lists:sort(
 		[{S, A} || {H, A} <- Alts,
-			   prefix(Prefix, S=hd(io_lib:fwrite("~w",[H])))]),
+			   prefix(Prefix, S=flat_write(H))]),
     case longest_common_head([N || {N, _} <- Matches]) of
  	{partial, []} ->
  	    {no, [], Matches}; % format_matches(Matches)};
  	{partial, Str} ->
- 	    case nthtail(Len, Str) of
+            case string:slice(Str, Len) of
  		[] ->
 		    {yes, [], Matches}; % format_matches(Matches)};
  		Remain ->
@@ -94,18 +94,21 @@ match(Prefix, Alts, Extra0) ->
 			{"(",[{Str,0}]} -> "()";
 			{_,_} -> Extra0
 		    end,
-	    {yes, nthtail(Len, Str) ++ Extra, []};
+	    {yes, string:slice(Str, Len) ++ Extra, []};
  	no ->
  	    {no, [], []}
     end.
 
+flat_write(T) ->
+    lists:flatten(io_lib:fwrite("~tw",[T])).
+
 %% Return the list of names L in multiple columns.
 format_matches(L) ->
     {S1, Dots} = format_col(lists:sort(L), []),
     S = case Dots of
             true ->
                 {_, Prefix} = longest_common_head(vals(L)),
-                PrefixLen = length(Prefix),
+                PrefixLen = string:length(Prefix),
                 case PrefixLen =< 3 of
                     true -> S1; % Do not replace the prefix with "...".
                     false ->
@@ -128,7 +131,7 @@ format_col([A|T], Width, Len, Acc0, LL, Dots) ->
     {H0, R} = format_val(A),
     Hmax = LL - length(R),
     {H, NewDots} =
-        case length(H0) > Hmax of
+        case string:length(H0) > Hmax of
             true -> {io_lib:format("~-*ts", [Hmax - 3, H0]) ++ "...", true};
             false -> {H0, Dots}
         end,
@@ -149,12 +152,12 @@ format_val(H) ->
 field_width(L, LL) -> field_width(L, 0, LL).
 
 field_width([{H,_}|T], W, LL) ->
-    case length(H) of
+    case string:length(H) of
         L when L > W -> field_width(T, L, LL);
         _ -> field_width(T, W, LL)
     end;
 field_width([H|T], W, LL) ->
-    case length(H) of
+    case string:length(H) of
         L when L > W -> field_width(T, L, LL);
         _ -> field_width(T, W, LL)
     end;
@@ -169,10 +172,11 @@ vals([S|L]) -> [S|vals(L)].
 
 leading_dots([], _Len) -> [];
 leading_dots([{H, I}|L], Len) ->
-    [{"..." ++ nthtail(Len, H), I}|leading_dots(L, Len)];
+    [{"..." ++ string:slice(H, Len), I}|leading_dots(L, Len)];
 leading_dots([H|L], Len) ->
-    ["..." ++ nthtail(Len, H)|leading_dots(L, Len)].
+    ["..." ++ string:slice(H, Len)|leading_dots(L, Len)].
 
+%% Strings are handled naively, but it should be OK here.
 longest_common_head([]) ->
     no;
 longest_common_head(LL) ->
diff --git a/lib/stdlib/src/error_logger_file_h.erl b/lib/stdlib/src/error_logger_file_h.erl
index b7c193f965..58da0cbdd6 100644
--- a/lib/stdlib/src/error_logger_file_h.erl
+++ b/lib/stdlib/src/error_logger_file_h.erl
@@ -126,7 +126,7 @@ format_body(State, [{Format,Args}|T]) ->
 		S0
 	catch
 	    _:_ ->
-		format(State, "ERROR: ~p - ~p\n", [Format,Args])
+		format(State, "ERROR: ~tp - ~tp\n", [Format,Args])
 	end,
     [S|format_body(State, T)];
 format_body(_State, []) ->
@@ -165,44 +165,26 @@ parse_event({warning_report, _GL, {Pid, std_warning, Args}}) ->
 parse_event(_) -> ignore.
 
 format_term(Term) when is_list(Term) ->
-    case string_p(Term) of
+    case string_p(lists:flatten(Term)) of
 	true ->
-	    [{"~s\n",[Term]}];
+	    [{"~ts\n",[Term]}];
 	false ->
 	    format_term_list(Term)
     end;
 format_term(Term) ->
-    [{"~p\n",[Term]}].
+    [{"~tp\n",[Term]}].
 
 format_term_list([{Tag,Data}|T]) ->
-    [{"    ~p: ~p\n",[Tag,Data]}|format_term_list(T)];
+    [{"    ~tp: ~tp\n",[Tag,Data]}|format_term_list(T)];
 format_term_list([Data|T]) ->
-    [{"    ~p\n",[Data]}|format_term_list(T)];
+    [{"    ~tp\n",[Data]}|format_term_list(T)];
 format_term_list([]) ->
-    [];
-format_term_list(_) ->
-    %% Continue to allow non-proper lists for now.
-    %% FIXME: Remove this clause in OTP 19.
     [].
 
 string_p([]) ->
     false;
-string_p(Term) ->
-    string_p1(Term).
-
-string_p1([H|T]) when is_integer(H), H >= $\s, H < 255 ->
-    string_p1(T);
-string_p1([$\n|T]) -> string_p1(T);
-string_p1([$\r|T]) -> string_p1(T);
-string_p1([$\t|T]) -> string_p1(T);
-string_p1([$\v|T]) -> string_p1(T);
-string_p1([$\b|T]) -> string_p1(T);
-string_p1([$\f|T]) -> string_p1(T);
-string_p1([$\e|T]) -> string_p1(T);
-string_p1([H|T]) when is_list(H) ->
-    string_p1(H) andalso string_p1(T);
-string_p1([]) -> true;
-string_p1(_) ->  false.
+string_p(FlatList) ->
+    io_lib:printable_list(FlatList).
 
 get_utc_config() ->
     %% SASL utc_log configuration overrides stdlib config
@@ -225,7 +207,7 @@ header(Time, Title) ->
     end.
 
 header({{Y,Mo,D},{H,Mi,S}}, Title, UTC) ->
-    io_lib:format("~n=~s==== ~p-~s-~p::~s:~s:~s ~s===~n",
+    io_lib:format("~n=~ts==== ~p-~s-~p::~s:~s:~s ~s===~n",
                   [Title,D,month(Mo),Y,t(H),t(Mi),t(S),UTC]).
 
 t(X) when is_integer(X) ->
diff --git a/lib/stdlib/src/error_logger_tty_h.erl b/lib/stdlib/src/error_logger_tty_h.erl
index 8f0d7b0362..fa940b7264 100644
--- a/lib/stdlib/src/error_logger_tty_h.erl
+++ b/lib/stdlib/src/error_logger_tty_h.erl
@@ -39,13 +39,16 @@
 	{user,
 	 prev_handler,
 	 io_mod=io,
-	 depth=unlimited}).
+	 depth=unlimited,
+         modifier=""}).
 
 %% This one is used when we takeover from the simple error_logger.
 init({[], {error_logger, Buf}}) ->
     User = set_group_leader(),
     Depth = error_logger:get_format_depth(),
-    State = #st{user=User,prev_handler=error_logger,depth=Depth},
+    Modifier = modifier(),
+    State = #st{user=User,prev_handler=error_logger,
+                depth=Depth,modifier=Modifier},
     write_events(State, Buf),
     {ok, State};
 %% This one is used if someone took over from us, and now wants to
@@ -57,7 +60,8 @@ init({[], {error_logger_tty_h, PrevHandler}}) ->
 init([]) ->
     User = set_group_leader(),
     Depth = error_logger:get_format_depth(),
-    {ok, #st{user=User,prev_handler=[],depth=Depth}}.
+    Modifier = modifier(),
+    {ok, #st{user=User,prev_handler=[],depth=Depth,modifier=Modifier}}.
 
 handle_event({_Type, GL, _Msg}, State) when node(GL) =/= node() ->
     {ok, State};
@@ -91,8 +95,9 @@ code_change(_OldVsn, State, _Extra) ->
 write_event(Event, IoMod) ->
     do_write_event(#st{io_mod=IoMod}, Event).
 
-write_event(Event, IoMod, Depth) ->
-    do_write_event(#st{io_mod=IoMod,depth=Depth}, Event).
+write_event(Event, IoMod, {Depth, Enc}) ->
+    Modifier = modifier(Enc),
+    do_write_event(#st{io_mod=IoMod,depth=Depth,modifier=Modifier}, Event).
 
 
 %%% ------------------------------------------------------
@@ -120,12 +125,12 @@ write_events(State, [Ev|Es]) ->
 write_events(_State, []) ->
     ok.
 
-do_write_event(State, {Time, Event}) ->
-    case parse_event(Event) of
+do_write_event(#st{modifier=M}=State, {Time, Event}) ->
+    case parse_event(Event,M) of
 	ignore ->
 	    ok;
 	{Title,Pid,FormatList} ->
-	    Header = header(Time, Title),
+	    Header = header(Time, Title, M),
 	    Body = format_body(State, FormatList),
 	    AtNode = if
 			 node(Pid) =/= node() ->
@@ -144,13 +149,13 @@ do_write_event(State, {Time, Event}) ->
 do_write_event(_, _) ->
     ok.
 
-format_body(State, [{Format,Args}|T]) ->
+format_body(#st{modifier=M}=State, [{Format,Args}|T]) ->
     S = try format(State, Format, Args) of
 	    S0 ->
 		S0
 	catch
 	    _:_ ->
-		format(State, "ERROR: ~p - ~p\n", [Format,Args])
+		format(State, "ERROR: ~"++M++"p - ~"++M++"p\n", [Format,Args])
 	end,
     [S|format_body(State, T)];
 format_body(_State, []) ->
@@ -174,62 +179,41 @@ limit_format([H|T], Depth) ->
 limit_format([], _) ->
     [].
 
-parse_event({error, _GL, {Pid, Format, Args}}) ->
+parse_event({error, _GL, {Pid, Format, Args}},_) ->
     {"ERROR REPORT",Pid,[{Format,Args}]};
-parse_event({info_msg, _GL, {Pid, Format, Args}}) ->
+parse_event({info_msg, _GL, {Pid, Format, Args}},_) ->
     {"INFO REPORT",Pid,[{Format, Args}]};
-parse_event({warning_msg, _GL, {Pid, Format, Args}}) ->
+parse_event({warning_msg, _GL, {Pid, Format, Args}},_) ->
     {"WARNING REPORT",Pid,[{Format,Args}]};
-parse_event({error_report, _GL, {Pid, std_error, Args}}) ->
-    {"ERROR REPORT",Pid,format_term(Args)};
-parse_event({info_report, _GL, {Pid, std_info, Args}}) ->
-    {"INFO REPORT",Pid,format_term(Args)};
-parse_event({warning_report, _GL, {Pid, std_warning, Args}}) ->
-    {"WARNING REPORT",Pid,format_term(Args)};
-parse_event(_) -> ignore.
-
-format_term(Term) when is_list(Term) ->
-    case string_p(Term) of
+parse_event({error_report, _GL, {Pid, std_error, Args}},M) ->
+    {"ERROR REPORT",Pid,format_term(Args,M)};
+parse_event({info_report, _GL, {Pid, std_info, Args}},M) ->
+    {"INFO REPORT",Pid,format_term(Args,M)};
+parse_event({warning_report, _GL, {Pid, std_warning, Args}},M) ->
+    {"WARNING REPORT",Pid,format_term(Args,M)};
+parse_event(_,_) -> ignore.
+
+format_term(Term,M) when is_list(Term) ->
+    case string_p(lists:flatten(Term)) of
 	true ->
-	    [{"~s\n",[Term]}];
+	    [{"~"++M++"s\n",[Term]}];
 	false ->
-	    format_term_list(Term)
+	    format_term_list(Term,M)
     end;
-format_term(Term) ->
-    [{"~p\n",[Term]}].
-
-format_term_list([{Tag,Data}|T]) ->
-    [{"    ~p: ~p\n",[Tag,Data]}|format_term_list(T)];
-format_term_list([Data|T]) ->
-    [{"    ~p\n",[Data]}|format_term_list(T)];
-format_term_list([]) ->
-    [];
-format_term_list(_) ->
-    %% Continue to allow non-proper lists for now.
-    %% FIXME: Remove this clause in OTP 19.
+format_term(Term,M) ->
+    [{"~"++M++"p\n",[Term]}].
+
+format_term_list([{Tag,Data}|T],M) ->
+    [{"    ~"++M++"p: ~"++M++"p\n",[Tag,Data]}|format_term_list(T,M)];
+format_term_list([Data|T],M) ->
+    [{"    ~"++M++"p\n",[Data]}|format_term_list(T,M)];
+format_term_list([],_) ->
     [].
 
 string_p([]) ->
     false;
-string_p(Term) ->
-    string_p1(Term).
-
-string_p1([H|T]) when is_integer(H), H >= $\s, H < 255 ->
-    string_p1(T);
-string_p1([$\n|T]) -> string_p1(T);
-string_p1([$\r|T]) -> string_p1(T);
-string_p1([$\t|T]) -> string_p1(T);
-string_p1([$\v|T]) -> string_p1(T);
-string_p1([$\b|T]) -> string_p1(T);
-string_p1([$\f|T]) -> string_p1(T);
-string_p1([$\e|T]) -> string_p1(T);
-string_p1([H|T]) when is_list(H) ->
-    case string_p1(H) of
-	true -> string_p1(T);
-	_    -> false
-    end;
-string_p1([]) -> true;
-string_p1(_) ->  false.
+string_p(FlatList) ->
+    io_lib:printable_list(FlatList).
 
 get_utc_config() ->
     %% SASL utc_log configuration overrides stdlib config
@@ -243,16 +227,16 @@ get_utc_config() ->
             end
     end.
 
-header(Time, Title) ->
+header(Time, Title, M) ->
     case get_utc_config() of
         true ->
-            header(Time, Title, "UTC ");
+            header(Time, Title, "UTC ", M);
         _ ->
-            header(calendar:universal_time_to_local_time(Time), Title, "")
+            header(calendar:universal_time_to_local_time(Time), Title, "", M)
     end.
 
-header({{Y,Mo,D},{H,Mi,S}}, Title, UTC) ->
-    io_lib:format("~n=~s==== ~p-~s-~p::~s:~s:~s ~s===~n",
+header({{Y,Mo,D},{H,Mi,S}}, Title, UTC, M) ->
+    io_lib:format("~n=~"++M++"s==== ~p-~s-~p::~s:~s:~s ~s===~n",
                  [Title,D,month(Mo),Y,t(H),t(Mi),t(S),UTC]).
 
 t(X) when is_integer(X) ->
@@ -274,3 +258,13 @@ month(9) -> "Sep";
 month(10) -> "Oct";
 month(11) -> "Nov";
 month(12) -> "Dec".
+
+modifier() ->
+    modifier(encoding()).
+modifier(latin1) ->
+    "";
+modifier(_) ->
+    "t".
+
+encoding() ->
+    proplists:get_value(encoding,io:getopts(),latin1).
diff --git a/lib/stdlib/src/escript.erl b/lib/stdlib/src/escript.erl
index 2093916a7c..2b9d8ff65b 100644
--- a/lib/stdlib/src/escript.erl
+++ b/lib/stdlib/src/escript.erl
@@ -860,7 +860,7 @@ code_handler(Name, Args, Dict, File) ->
                     %% io:format("Calling:~p~n",[{Mod,Name,Args}]),
                     apply(Mod, Name, Args);
                 error ->
-                    io:format("Script does not export ~w/~w\n", [Name,Arity]),
+                    io:format("Script does not export ~tw/~w\n", [Name,Arity]),
                     my_halt(127)
             end
     end.
diff --git a/lib/stdlib/src/ets.erl b/lib/stdlib/src/ets.erl
index 898b2f5bba..b5d3cd3c8d 100644
--- a/lib/stdlib/src/ets.erl
+++ b/lib/stdlib/src/ets.erl
@@ -1693,7 +1693,7 @@ choice(Height, Width, P, Mode, Tab, Key, Turn, Opos) ->
 		  end,
 	    choice(Height, Width, P, Mode, Tab, Key, Turn, Opos);
 	[$/|Regexp]   -> %% from regexp
-	    case re:compile(nonl(Regexp)) of
+	    case re:compile(nonl(Regexp),[unicode]) of
 		{ok,Re} ->
 		    re_search(Height, Width, Tab, ets:first(Tab), Re, 1, 1);
 		{error,{ErrorString,_Pos}} ->
diff --git a/lib/stdlib/src/gen.erl b/lib/stdlib/src/gen.erl
index 32f43fc706..33af0aed8f 100644
--- a/lib/stdlib/src/gen.erl
+++ b/lib/stdlib/src/gen.erl
@@ -422,7 +422,7 @@ debug_options(Name, Opts) ->
 	    try sys:debug_options(Options)
 	    catch _:_ ->
 		    error_logger:format(
-		      "~p: ignoring erroneous debug options - ~p~n",
+		      "~tp: ignoring erroneous debug options - ~tp~n",
 		      [Name,Options]),
 		    []
 	    end;
diff --git a/lib/stdlib/src/gen_event.erl b/lib/stdlib/src/gen_event.erl
index da2b0da3ca..a9b98911e2 100644
--- a/lib/stdlib/src/gen_event.erl
+++ b/lib/stdlib/src/gen_event.erl
@@ -441,15 +441,15 @@ system_replace_state(StateFun, [ServerName, MSL, HibernateAfterTimeout, Hib]) ->
 print_event(Dev, {in, Msg}, Name) ->
     case Msg of
 	{notify, Event} ->
-	    io:format(Dev, "*DBG* ~p got event ~p~n", [Name, Event]);
+	    io:format(Dev, "*DBG* ~tp got event ~tp~n", [Name, Event]);
 	{_,_,{call, Handler, Query}} ->
-	    io:format(Dev, "*DBG* ~p(~p) got call ~p~n",
+	    io:format(Dev, "*DBG* ~tp(~tp) got call ~tp~n",
 		      [Name, Handler, Query]);
 	_ ->
-	    io:format(Dev, "*DBG* ~p got ~p~n", [Name, Msg])
+	    io:format(Dev, "*DBG* ~tp got ~tp~n", [Name, Msg])
     end;
 print_event(Dev, Dbg, Name) ->
-    io:format(Dev, "*DBG* ~p : ~p~n", [Name, Dbg]).
+    io:format(Dev, "*DBG* ~tp : ~tp~n", [Name, Dbg]).
 
 
 %% server_add_handler(Handler, Args, MSL) -> {Ret, MSL'}.
@@ -582,8 +582,8 @@ server_update(Handler1, Func, Event, SName) ->
 			 remove, SName, normal),
 	    no;
         {'EXIT', {undef, [{Mod1, handle_info, [_,_], _}|_]}} ->
-            error_logger:warning_msg("** Undefined handle_info in ~p~n"
-                                     "** Unhandled message: ~p~n", [Mod1, Event]),
+            error_logger:warning_msg("** Undefined handle_info in ~tp~n"
+                                     "** Unhandled message: ~tp~n", [Mod1, Event]),
            {ok, Handler1};
 	Other ->
 	    do_terminate(Mod1, Handler1, {error, Other}, State,
@@ -767,10 +767,10 @@ report_error(Handler, Reason, State, LastIn, SName) ->
 		       State
 	       end,
     error_msg("** gen_event handler ~p crashed.~n"
-	      "** Was installed in ~p~n"
-	      "** Last event was: ~p~n"
-	      "** When handler state == ~p~n"
-	      "** Reason == ~p~n",
+	      "** Was installed in ~tp~n"
+	      "** Last event was: ~tp~n"
+	      "** When handler state == ~tp~n"
+	      "** Reason == ~tp~n",
 	      [handler(Handler),SName,LastIn,FmtState,Reason1]).
 
 handler(Handler) when not Handler#handler.id ->
diff --git a/lib/stdlib/src/gen_fsm.erl b/lib/stdlib/src/gen_fsm.erl
index 9ef0ca818c..96a53426e2 100644
--- a/lib/stdlib/src/gen_fsm.erl
+++ b/lib/stdlib/src/gen_fsm.erl
@@ -452,30 +452,30 @@ system_replace_state(StateFun, [Name, StateName, StateData, Mod, Time, Hibernate
 print_event(Dev, {in, Msg}, {Name, StateName}) ->
     case Msg of
 	{'$gen_event', Event} ->
-	    io:format(Dev, "*DBG* ~p got event ~p in state ~w~n",
+	    io:format(Dev, "*DBG* ~tp got event ~tp in state ~tw~n",
 		      [Name, Event, StateName]);
 	{'$gen_all_state_event', Event} ->
 	    io:format(Dev,
-		      "*DBG* ~p got all_state_event ~p in state ~w~n",
+		      "*DBG* ~tp got all_state_event ~tp in state ~tw~n",
 		      [Name, Event, StateName]);
 	{timeout, Ref, {'$gen_timer', Message}} ->
 	    io:format(Dev,
-		      "*DBG* ~p got timer ~p in state ~w~n",
+		      "*DBG* ~tp got timer ~tp in state ~tw~n",
 		      [Name, {timeout, Ref, Message}, StateName]);
 	{timeout, _Ref, {'$gen_event', Event}} ->
 	    io:format(Dev,
-		      "*DBG* ~p got timer ~p in state ~w~n",
+		      "*DBG* ~tp got timer ~tp in state ~tw~n",
 		      [Name, Event, StateName]);
 	_ ->
-	    io:format(Dev, "*DBG* ~p got ~p in state ~w~n",
+	    io:format(Dev, "*DBG* ~tp got ~tp in state ~tw~n",
 		      [Name, Msg, StateName])
     end;
 print_event(Dev, {out, Msg, To, StateName}, Name) ->
-    io:format(Dev, "*DBG* ~p sent ~p to ~w~n"
-	           "      and switched to state ~w~n",
+    io:format(Dev, "*DBG* ~tp sent ~tp to ~tw~n"
+	           "      and switched to state ~tw~n",
 	      [Name, Msg, To, StateName]);
 print_event(Dev, return, {Name, StateName}) ->
-    io:format(Dev, "*DBG* ~p switched to state ~w~n",
+    io:format(Dev, "*DBG* ~tp switched to state ~tw~n",
 	      [Name, StateName]).
 
 handle_msg(Msg, Parent, Name, StateName, StateData, Mod, _Time, HibernateAfterTimeout) -> %No debug here
@@ -500,7 +500,7 @@ handle_msg(Msg, Parent, Name, StateName, StateData, Mod, _Time, HibernateAfterTi
 	    exit(R);
         {'EXIT', {undef, [{Mod, handle_info, [_,_,_], _}|_]}} ->
             error_logger:warning_msg("** Undefined handle_info in ~p~n"
-                                     "** Unhandled message: ~p~n", [Mod, Msg]),
+                                     "** Unhandled message: ~tp~n", [Mod, Msg]),
             loop(Parent, Name, StateName, StateData, Mod, infinity, HibernateAfterTimeout, []);
 	{'EXIT', What} ->
 	    terminate(What, Name, Msg, Mod, StateName, StateData, []);
@@ -620,29 +620,29 @@ error_info(Reason, Name, Msg, StateName, StateData, Debug) ->
 	    _ ->
 		Reason
 	end,
-    Str = "** State machine ~p terminating \n" ++
+    Str = "** State machine ~tp terminating \n" ++
 	get_msg_str(Msg) ++
-	"** When State == ~p~n"
-        "**      Data  == ~p~n"
-        "** Reason for termination = ~n** ~p~n",
+	"** When State == ~tp~n"
+        "**      Data  == ~tp~n"
+        "** Reason for termination = ~n** ~tp~n",
     format(Str, [Name, get_msg(Msg), StateName, StateData, Reason1]),
     sys:print_log(Debug),
     ok.
 
 get_msg_str({'$gen_event', _Event}) ->
-    "** Last event in was ~p~n";
+    "** Last event in was ~tp~n";
 get_msg_str({'$gen_sync_event', _Event}) ->
-    "** Last sync event in was ~p~n";
+    "** Last sync event in was ~tp~n";
 get_msg_str({'$gen_all_state_event', _Event}) ->
-    "** Last event in was ~p (for all states)~n";
+    "** Last event in was ~tp (for all states)~n";
 get_msg_str({'$gen_sync_all_state_event', _Event}) ->
-    "** Last sync event in was ~p (for all states)~n";
+    "** Last sync event in was ~tp (for all states)~n";
 get_msg_str({timeout, _Ref, {'$gen_timer', _Msg}}) ->
-    "** Last timer event in was ~p~n";
+    "** Last timer event in was ~tp~n";
 get_msg_str({timeout, _Ref, {'$gen_event', _Msg}}) ->
-    "** Last timer event in was ~p~n";
+    "** Last timer event in was ~tp~n";
 get_msg_str(_Msg) ->
-    "** Last message in was ~p~n".
+    "** Last message in was ~tp~n".
 
 get_msg({'$gen_event', Event}) -> Event;
 get_msg({'$gen_sync_event', Event}) -> Event;
diff --git a/lib/stdlib/src/gen_server.erl b/lib/stdlib/src/gen_server.erl
index a3d53efd0d..7daa7a9fe4 100644
--- a/lib/stdlib/src/gen_server.erl
+++ b/lib/stdlib/src/gen_server.erl
@@ -621,7 +621,7 @@ try_dispatch(Mod, Func, Msg, State) ->
             case erlang:function_exported(Mod, handle_info, 2) of
                 false ->
                     error_logger:warning_msg("** Undefined handle_info in ~p~n"
-                                             "** Unhandled message: ~p~n",
+                                             "** Unhandled message: ~tp~n",
                                              [Mod, Msg]),
                     {ok, {noreply, State}};
                 true ->
@@ -785,21 +785,21 @@ system_replace_state(StateFun, [Name, State, Mod, Time, HibernateAfterTimeout])
 print_event(Dev, {in, Msg}, Name) ->
     case Msg of
 	{'$gen_call', {From, _Tag}, Call} ->
-	    io:format(Dev, "*DBG* ~p got call ~p from ~w~n",
+	    io:format(Dev, "*DBG* ~tp got call ~tp from ~w~n",
 		      [Name, Call, From]);
 	{'$gen_cast', Cast} ->
-	    io:format(Dev, "*DBG* ~p got cast ~p~n",
+	    io:format(Dev, "*DBG* ~tp got cast ~tp~n",
 		      [Name, Cast]);
 	_ ->
-	    io:format(Dev, "*DBG* ~p got ~p~n", [Name, Msg])
+	    io:format(Dev, "*DBG* ~tp got ~tp~n", [Name, Msg])
     end;
 print_event(Dev, {out, Msg, To, State}, Name) ->
-    io:format(Dev, "*DBG* ~p sent ~p to ~w, new state ~w~n", 
+    io:format(Dev, "*DBG* ~tp sent ~tp to ~w, new state ~tp~n",
 	      [Name, Msg, To, State]);
 print_event(Dev, {noreply, State}, Name) ->
-    io:format(Dev, "*DBG* ~p new state ~w~n", [Name, State]);
+    io:format(Dev, "*DBG* ~tp new state ~tp~n", [Name, State]);
 print_event(Dev, Event, Name) ->
-    io:format(Dev, "*DBG* ~p dbg  ~p~n", [Name, Event]).
+    io:format(Dev, "*DBG* ~tp dbg  ~tp~n", [Name, Event]).
 
 
 %%% ---------------------------------------------------
@@ -881,10 +881,10 @@ error_info(Reason, Name, From, Msg, State, Debug) ->
 	end,    
     {ClientFmt, ClientArgs} = client_stacktrace(From),
     LimitedState = error_logger:limit_term(State),
-    error_logger:format("** Generic server ~p terminating \n"
-                        "** Last message in was ~p~n"
-                        "** When Server state == ~p~n"
-                        "** Reason for termination == ~n** ~p~n" ++ ClientFmt,
+    error_logger:format("** Generic server ~tp terminating \n"
+                        "** Last message in was ~tp~n"
+                        "** When Server state == ~tp~n"
+                        "** Reason for termination == ~n** ~tp~n" ++ ClientFmt,
                         [Name, Msg, LimitedState, Reason1] ++ ClientArgs),
     sys:print_log(Debug),
     ok.
@@ -898,11 +898,11 @@ client_stacktrace(From) when is_pid(From), node(From) =:= node() ->
             {"** Client ~p is dead~n", [From]};
         [{current_stacktrace, Stacktrace}, {registered_name, []}]  ->
             {"** Client ~p stacktrace~n"
-             "** ~p~n",
+             "** ~tp~n",
              [From, Stacktrace]};
         [{current_stacktrace, Stacktrace}, {registered_name, Name}]  ->
-            {"** Client ~p stacktrace~n"
-             "** ~p~n",
+            {"** Client ~tp stacktrace~n"
+             "** ~tp~n",
              [Name, Stacktrace]}
     end;
 client_stacktrace(From) when is_pid(From) ->
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl
index b5e9da1e66..1110d18af6 100644
--- a/lib/stdlib/src/gen_statem.erl
+++ b/lib/stdlib/src/gen_statem.erl
@@ -791,34 +791,34 @@ format_status(
 
 print_event(Dev, {in,Event}, {Name,State}) ->
     io:format(
-      Dev, "*DBG* ~p receive ~s in state ~p~n",
+      Dev, "*DBG* ~tp receive ~ts in state ~tp~n",
       [Name,event_string(Event),State]);
 print_event(Dev, {out,Reply,{To,_Tag}}, {Name,State}) ->
     io:format(
-      Dev, "*DBG* ~p send ~p to ~p from state ~p~n",
+      Dev, "*DBG* ~tp send ~tp to ~p from state ~tp~n",
       [Name,Reply,To,State]);
 print_event(Dev, {terminate,Reason}, {Name,State}) ->
     io:format(
-      Dev, "*DBG* ~p terminate ~p in state ~p~n",
+      Dev, "*DBG* ~tp terminate ~tp in state ~tp~n",
       [Name,Reason,State]);
 print_event(Dev, {Tag,Event,NextState}, {Name,State}) ->
     StateString =
 	case NextState of
 	    State ->
-		io_lib:format("~p", [State]);
+		io_lib:format("~tp", [State]);
 	    _ ->
-		io_lib:format("~p => ~p", [State,NextState])
+		io_lib:format("~tp => ~tp", [State,NextState])
 	end,
     io:format(
-      Dev, "*DBG* ~p ~w ~s in state ~s~n",
+      Dev, "*DBG* ~tp ~tw ~ts in state ~ts~n",
       [Name,Tag,event_string(Event),StateString]).
 
 event_string(Event) ->
     case Event of
 	{{call,{Pid,_Tag}},Request} ->
-	    io_lib:format("call ~p from ~w", [Request,Pid]);
+	    io_lib:format("call ~tp from ~w", [Request,Pid]);
 	{EventType,EventContent} ->
-	    io_lib:format("~w ~p", [EventType,EventContent])
+	    io_lib:format("~tw ~tp", [EventType,EventContent])
     end.
 
 sys_debug(Debug, #{name := Name}, State, Entry) ->
@@ -1732,25 +1732,25 @@ error_info(
 		 CallbackMode
 	 end,
     error_logger:format(
-      "** State machine ~p terminating~n" ++
+      "** State machine ~tp terminating~n" ++
 	  case Q of
 	      [] -> "";
-	      _ -> "** Last event = ~p~n"
+	      _ -> "** Last event = ~tp~n"
 	  end ++
-	  "** When server state  = ~p~n" ++
-	  "** Reason for termination = ~w:~p~n" ++
+	  "** When server state  = ~tp~n" ++
+	  "** Reason for termination = ~w:~tp~n" ++
 	  "** Callback mode = ~p~n" ++
 	  case Q of
-	      [_,_|_] -> "** Queued = ~p~n";
+	      [_,_|_] -> "** Queued = ~tp~n";
 	      _ -> ""
 	  end ++
 	  case P of
 	      [] -> "";
-	      _ -> "** Postponed = ~p~n"
+	      _ -> "** Postponed = ~tp~n"
 	  end ++
 	  case FixedStacktrace of
 	      [] -> "";
-	      _ -> "** Stacktrace =~n**  ~p~n"
+	      _ -> "** Stacktrace =~n**  ~tp~n"
 	  end,
       [Name |
        case Q of
diff --git a/lib/stdlib/src/proc_lib.erl b/lib/stdlib/src/proc_lib.erl
index d4d1bdccec..8e10cbe93b 100644
--- a/lib/stdlib/src/proc_lib.erl
+++ b/lib/stdlib/src/proc_lib.erl
@@ -823,22 +823,22 @@ to_string(A, _) ->
     io_lib:write_atom(A).
 
 pp_fun({Enc,Depth}) ->
-    {Letter,Tl} = case Depth of
-		      unlimited -> {"p",[]};
-		      _ -> {"P",[Depth]}
-		  end,
-    P = modifier(Enc) ++ Letter,
+    {P,Tl} = p(Enc, Depth),
     fun(Term, I) -> 
             io_lib:format("~." ++ integer_to_list(I) ++ P, [Term|Tl])
     end.
 
-format_tag(Indent, Tag, Data, {_Enc,Depth}) ->
-    case Depth of
-	unlimited ->
-	    io_lib:format("~s~p: ~80.18p~n", [Indent, Tag, Data]);
-	_ ->
-            io_lib:format("~s~p: ~80.18P~n", [Indent, Tag, Data, Depth])
-    end.
+format_tag(Indent, Tag, Data, {Enc,Depth}) ->
+    {P,Tl} = p(Enc, Depth),
+    io_lib:format("~s~p: ~80.18" ++ P ++ "\n", [Indent, Tag, Data|Tl]).
+
+p(Encoding, Depth) ->
+    {Letter, Tl}  = case Depth of
+                        unlimited -> {"p", []};
+                        _         -> {"P", [Depth]}
+                    end,
+    P = modifier(Encoding) ++ Letter,
+    {P, Tl}.
 
 modifier(latin1) -> "";
 modifier(_) -> "t".
diff --git a/lib/stdlib/src/qlc.erl b/lib/stdlib/src/qlc.erl
index 535ca57a6b..f11f9d0a0b 100644
--- a/lib/stdlib/src/qlc.erl
+++ b/lib/stdlib/src/qlc.erl
@@ -1132,7 +1132,7 @@ wait_for_request(Parent, MonRef, Post) ->
             wait_for_request(Parent, MonRef, Post);
         Other ->
             error_logger:error_msg(
-              "The qlc cursor ~w received an unexpected message:\n~p\n", 
+              "The qlc cursor ~w received an unexpected message:\n~tp\n",
               [self(), Other]),
             wait_for_request(Parent, MonRef, Post)
     end.
diff --git a/lib/stdlib/src/shell.erl b/lib/stdlib/src/shell.erl
index 26b3960f4f..212b143b1d 100644
--- a/lib/stdlib/src/shell.erl
+++ b/lib/stdlib/src/shell.erl
@@ -1459,7 +1459,7 @@ check_env(V) ->
         {ok, Val} ->
             Txt = io_lib:fwrite
                     ("Invalid value of STDLIB configuration parameter"
-                     "~w: ~tp\n", [V, Val]),
+                     "~tw: ~tp\n", [V, Val]),
 	    error_logger:info_report(lists:flatten(Txt))
     end.
 	    
diff --git a/lib/stdlib/src/slave.erl b/lib/stdlib/src/slave.erl
index 5b5c328c0c..d7cf6386f5 100644
--- a/lib/stdlib/src/slave.erl
+++ b/lib/stdlib/src/slave.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2017. All Rights Reserved.
 %% 
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -77,7 +77,7 @@ start_pseudo(_,_,_) -> ok.  %% It's already there
       Pid :: pid().
 
 relay({badrpc,Reason}) ->
-    error_msg(" ** exiting relay server ~w :~w  **~n", [self(),Reason]),
+    error_msg(" ** exiting relay server ~w :~tw  **~n", [self(),Reason]),
     exit(Reason);
 relay(undefined) ->
     error_msg(" ** exiting relay server ~w  **~n", [self()]),
diff --git a/lib/stdlib/src/supervisor.erl b/lib/stdlib/src/supervisor.erl
index 1cd65fbf18..7920e55930 100644
--- a/lib/stdlib/src/supervisor.erl
+++ b/lib/stdlib/src/supervisor.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2017. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -628,7 +628,7 @@ handle_info({'EXIT', Pid, Reason}, State) ->
     end;
 
 handle_info(Msg, State) ->
-    error_logger:error_msg("Supervisor received unexpected message: ~p~n", 
+    error_logger:error_msg("Supervisor received unexpected message: ~tp~n",
 			   [Msg]),
     {noreply, State}.
 
diff --git a/lib/stdlib/test/Makefile b/lib/stdlib/test/Makefile
index 72211332e9..7b79dcf04d 100644
--- a/lib/stdlib/test/Makefile
+++ b/lib/stdlib/test/Makefile
@@ -36,6 +36,7 @@ MODULES= \
 	ets_tough_SUITE \
 	expand_test \
 	expand_test1 \
+	unicode_expand \
 	ExpandTestCaps \
 	ExpandTestCaps1 \
 	filelib_SUITE \
diff --git a/lib/stdlib/test/edlin_expand_SUITE.erl b/lib/stdlib/test/edlin_expand_SUITE.erl
index 1f694ea549..5c2b1965ba 100644
--- a/lib/stdlib/test/edlin_expand_SUITE.erl
+++ b/lib/stdlib/test/edlin_expand_SUITE.erl
@@ -22,7 +22,7 @@
 	 init_per_testcase/2, end_per_testcase/2,
 	 init_per_group/2,end_per_group/2]).
 -export([normal/1, quoted_fun/1, quoted_module/1, quoted_both/1, erl_1152/1,
-         erl_352/1]).
+         erl_352/1, unicode/1]).
 
 -include_lib("common_test/include/ct.hrl").
 
@@ -37,7 +37,8 @@ suite() ->
      {timetrap,{minutes,1}}].
 
 all() -> 
-    [normal, quoted_fun, quoted_module, quoted_both, erl_1152, erl_352].
+    [normal, quoted_fun, quoted_module, quoted_both, erl_1152, erl_352,
+     unicode].
 
 groups() -> 
     [].
@@ -150,6 +151,7 @@ quoted_both(Config) when is_list(Config) ->
     {yes,"weird-fun-name'()",[]} = do_expand("'ExpandTestCaps1':'#"),
     ok.
 
+%% Note: pull request #1152.
 erl_1152(Config) when is_list(Config) ->
     "\n"++"foo"++"    "++[1089]++_ = do_format(["foo",[1089]]),
     ok.
@@ -226,6 +228,26 @@ check_trailing([I|Str], ArityStr, Suffix, Dots) ->
             Rest =:= Suffix
     end.
 
+unicode(Config) when is_list(Config) ->
+    {module,unicode_expand} = c:l('unicode_expand'),
+    {no,[],[{"'кlирилли́ческий атом'",0},
+            {"'кlирилли́ческий атом'",1},
+            {"'кlирилли́ческий атомB'",1},
+            {"module_info",0},
+            {"module_info",1}]} = do_expand("unicode_expand:"),
+    {yes,"рилли́ческий атом", []} = do_expand("unicode_expand:'кlи"),
+    {yes,"еский атом", []} = do_expand("unicode_expand:'кlирилли́ч"),
+    {yes,"(",[]} = do_expand("unicode_expand:'кlирилли́ческий атомB'"),
+    "\n'кlирилли́ческий атом'/0   'кlирилли́ческий атом'/1   "
+    "'кlирилли́ческий атомB'/1  \nmodule_info/0             "
+    "module_info/1             \n" =
+        do_format([{"'кlирилли́ческий атом'",0},
+                   {"'кlирилли́ческий атом'",1},
+                   {"'кlирилли́ческий атомB'",1},
+                   {"module_info",0},
+                   {"module_info",1}]),
+    ok.
+
 do_expand(String) ->
     edlin_expand:expand(lists:reverse(String)).
 
diff --git a/lib/stdlib/test/error_logger_h_SUITE.erl b/lib/stdlib/test/error_logger_h_SUITE.erl
index 30f96e0522..1f2a9fda0b 100644
--- a/lib/stdlib/test/error_logger_h_SUITE.erl
+++ b/lib/stdlib/test/error_logger_h_SUITE.erl
@@ -162,7 +162,7 @@ tty_log_open(Log) ->
 		{ok,D} -> D;
 		_ -> unlimited
 	    end,
-    error_logger:add_report_handler(?MODULE, {Fd,Depth}),
+    error_logger:add_report_handler(?MODULE, {Fd,Depth,latin1}),
     Fd.
 
 tty_log_close() ->
@@ -393,11 +393,11 @@ dl_format_1([], [], _, Facc, Aacc) ->
 %%% calling error_logger_tty_h:write_event/2.
 %%%
 
-init({_,_}=St) ->
+init({_,_,_}=St) ->
     {ok,St}.
 
-handle_event(Event, {Fd,Depth}=St) ->
-    case error_logger_tty_h:write_event(tag_event(Event), io_lib, Depth) of
+handle_event(Event, {Fd,Depth,Enc}=St) ->
+    case error_logger_tty_h:write_event(tag_event(Event), io_lib, {Depth,Enc}) of
 	ok ->
 	    ok;
 	Str when is_list(Str) ->
@@ -405,7 +405,7 @@ handle_event(Event, {Fd,Depth}=St) ->
     end,
     {ok,St}.
 
-terminate(_Reason, {Fd,_}) ->
+terminate(_Reason, {Fd,_,_}) ->
     ok = file:close(Fd),
     [].
 
diff --git a/lib/stdlib/test/proc_lib_SUITE.erl b/lib/stdlib/test/proc_lib_SUITE.erl
index c4fafe82a4..7686889360 100644
--- a/lib/stdlib/test/proc_lib_SUITE.erl
+++ b/lib/stdlib/test/proc_lib_SUITE.erl
@@ -552,14 +552,17 @@ t_format(_Config) ->
 
 t_format() ->
     error_logger:add_report_handler(?MODULE, self()),
-    Pid = proc_lib:spawn(fun t_format_looper/0),
+    Pid = proc_lib:spawn(fun '\x{aaa}t_format_looper'/0),
     HugeData = gb_sets:from_list(lists:seq(1, 100)),
-    Pid ! {die,HugeData},
+    SomeData1 = list_to_atom([246]),
+    SomeData2 = list_to_atom([1024]),
+    Pid ! {SomeData1,SomeData2},
+    Pid ! {die,{HugeData,SomeData1,SomeData2}},
     Report = receive
 		 {crash_report, Pid, Report0} -> Report0
 	     end,
-    Usz = do_test_format(Report, unlimited),
-    Tsz = do_test_format(Report, 20),
+    Usz = do_test_format(Report, latin1, unlimited),
+    Tsz = do_test_format(Report, latin1, 20),
 
     if
 	Tsz >= Usz ->
@@ -568,6 +571,16 @@ t_format() ->
 	    ok
     end,
 
+    UszU = do_test_format(Report, unicode, unlimited),
+    TszU = do_test_format(Report, unicode, 20),
+
+    if
+	TszU >= UszU ->
+	    ct:fail(failed);
+	true ->
+	    ok
+    end,
+
     ok.
 
 t_format_arbitrary(_Config) ->
@@ -597,15 +610,19 @@ do_test_format(Report, Encoding, Depth) ->
     io:format("*** Depth = ~p, Encoding = ~p", [Depth, Encoding]),
     S0 = proc_lib:format(Report, Encoding, Depth),
     S = lists:flatten(S0),
-    io:put_chars(S),
+    case Encoding of
+        latin1 -> io:format("~s\n", [S]);
+        _ -> io:format("~ts\n", [S])
+    end,
     length(S).
 
-t_format_looper() ->
+'\x{aaa}t_format_looper'() ->
     receive
 	{die,Data} ->
 	    exit(Data);
-	_ ->
-	    t_format_looper()
+	M ->
+            put(M, M),
+	    '\x{aaa}t_format_looper'()
     end.
 
 %%-----------------------------------------------------------------
diff --git a/lib/stdlib/test/unicode_expand.erl b/lib/stdlib/test/unicode_expand.erl
new file mode 100644
index 0000000000..41f741fa84
--- /dev/null
+++ b/lib/stdlib/test/unicode_expand.erl
@@ -0,0 +1,36 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(unicode_expand).
+
+-export(['кlирилли́ческий атом'/0, 'кlирилли́ческий атом'/1,
+        'кlирилли́ческий атомB'/1]).
+
+-export_type(['кlирилли́ческий атом'/0]).
+
+-type 'кlирилли́ческий атом'() :: integer().
+
+'кlирилли́ческий атом'() ->
+    'кlирилли́ческий атом'('кlирилли́ческий атом').
+
+'кlирилли́ческий атом'(_Atom) ->
+    ok.
+
+'кlирилли́ческий атомB'(_B) ->
+    true.