Merge branch 'bjorn/compiler/misc'

* bjorn/compiler/misc:
  beam_bool_SUITE: Cover one more line
  beam_utils_SUITE: Cover more lines in beam_utils
  beam_reorder: Don't confuse beam_validator
  beam_bool: Reject potentially unsafe optimization
  v3_core: Don't depend on sys_core_fold for cleaning up
  beam_type: Eliminate crash
  beam_type: Correct handling of setelement/3
  beam_validator: Handle cons literals better
  beam_validator: Keep better track of tuple literals

10 files changed, 326 insertions, 50 deletions

diff --git a/lib/compiler/src/beam_bool.erl b/lib/compiler/src/beam_bool.erl
index 359fdb6d3c..99e4ccb1e9 100644
--- a/lib/compiler/src/beam_bool.erl
+++ b/lib/compiler/src/beam_bool.erl
@@ -311,6 +311,8 @@ dst_regs([{set,[D],_,{bif,_,{f,_}}}|Is], Acc) ->
     dst_regs(Is, [D|Acc]);
 dst_regs([{set,[D],_,{alloc,_,{gc_bif,_,{f,_}}}}|Is], Acc) ->
     dst_regs(Is, [D|Acc]);
+dst_regs([{protected,_,Bl,_}|Is], Acc) ->
+    dst_regs(Bl, dst_regs(Is, Acc));
 dst_regs([_|Is], Acc) ->
     dst_regs(Is, Acc);
 dst_regs([], Acc) -> ordsets:from_list(Acc).
diff --git a/lib/compiler/src/beam_reorder.erl b/lib/compiler/src/beam_reorder.erl
index f1c0b3ef91..6a7c033ec6 100644
--- a/lib/compiler/src/beam_reorder.erl
+++ b/lib/compiler/src/beam_reorder.erl
@@ -87,6 +87,15 @@ reorder_1([{test,_,_,_}=I,
     %% instruction between the test instruction and the select
     %% instruction.
     reorder_1(Is, D, [S,I|Acc]);
+reorder_1([{test,_,{f,_},[Src|_]}=I|Is], D,
+	  [{get_tuple_element,Src,_,_}|_]=Acc) ->
+    %% We want to avoid code that can confuse beam_validator such as:
+    %%   is_tuple Fail Src
+    %%   test_arity Fail Src Arity
+    %%   is_map Fail Src
+    %%   get_tuple_element Src Pos Dst
+    %% Therefore, don't reorder the instructions in such cases.
+    reorder_1(Is, D, [I|Acc]);
 reorder_1([{test,_,{f,L},Ss}=I|Is0], D0,
 	  [{get_tuple_element,_,_,El}=G|Acc0]=Acc) ->
     case member(El, Ss) of
diff --git a/lib/compiler/src/beam_type.erl b/lib/compiler/src/beam_type.erl
index 5076c5eb96..acaf3ede66 100644
--- a/lib/compiler/src/beam_type.erl
+++ b/lib/compiler/src/beam_type.erl
@@ -513,12 +513,23 @@ update({call_ext,Ar,{extfunc,math,Math,Ar}}, Ts) ->
 	false -> tdb_kill_xregs(Ts)
     end;
 update({call_ext,3,{extfunc,erlang,setelement,3}}, Ts0) ->
-    Op = case tdb_find({x,1}, Ts0) of
-	     error -> kill;
-	     Info -> Info
-	 end,
-    Ts1 = tdb_kill_xregs(Ts0),
-    tdb_update([{{x,0},Op}], Ts1);
+    Ts = tdb_kill_xregs(Ts0),
+    case tdb_find({x,1}, Ts0) of
+	{tuple,Sz,_}=T0 ->
+	    T = case tdb_find({x,0}, Ts0) of
+		    {integer,{I,I}} when I > 1 ->
+			%% First element is not changed. The result
+			%% will have the same type.
+			T0;
+		    _ ->
+			%% Position is 1 or unknown. May change the
+			%% first element of the tuple.
+			{tuple,Sz,[]}
+		end,
+	    tdb_update([{{x,0},T}], Ts);
+	_ ->
+	    Ts
+    end;
 update({call,_Arity,_Func}, Ts) -> tdb_kill_xregs(Ts);
 update({call_ext,_Arity,_Func}, Ts) -> tdb_kill_xregs(Ts);
 update({make_fun2,_,_,_,_}, Ts) -> tdb_kill_xregs(Ts);
@@ -748,7 +759,7 @@ checkerror_2(OrigIs) -> [{set,[],[],fcheckerror}|OrigIs].
 %%%
 %%% {tuple,Size,First} means that the corresponding register contains a
 %%% tuple with *at least* Size elements.  An tuple with unknown
-%%% size is represented as {tuple,0}. First is either [] (meaning that
+%%% size is represented as {tuple,0,[]}. First is either [] (meaning that
 %%% the tuple's first element is unknown) or [FirstElement] (the contents
 %%% of the first element).
 %%%
@@ -785,21 +796,45 @@ tdb_copy({Tag,_}=S, D, Ts) when Tag =:= x; Tag =:= y ->
 	error -> orddict:erase(D, Ts);
 	Type -> orddict:store(D, Type, Ts)
     end;
-tdb_copy(Literal, D, Ts) -> orddict:store(D, Literal, Ts).
+tdb_copy(Literal, D, Ts) ->
+    Type = case Literal of
+	       {atom,_} -> Literal;
+	       {float,_} -> float;
+	       {integer,Int} -> {integer,{Int,Int}};
+	       {literal,[_|_]} -> nonempty_list;
+	       {literal,#{}} -> map;
+	       {literal,Tuple} when tuple_size(Tuple) >= 1 ->
+		   Lit = tag_literal(element(1, Tuple)),
+		   {tuple,tuple_size(Tuple),[Lit]};
+	       _ -> term
+	   end,
+    if
+	Type =:= term ->
+	    orddict:erase(D, Ts);
+	true ->
+	    verify_type(Type),
+	    orddict:store(D, Type, Ts)
+    end.
+
+tag_literal(A) when is_atom(A) -> {atom,A};
+tag_literal(F) when is_float(F) -> {float,F};
+tag_literal(I) when is_integer(I) -> {integer,I};
+tag_literal([]) -> nil;
+tag_literal(Lit) -> {literal,Lit}.
 
 %% tdb_update([UpdateOp], Db) -> NewDb
 %%        UpdateOp = {Register,kill}|{Register,NewInfo}
 %%  Updates a type database.  If a 'kill' operation is given, the type
 %%  information for that register will be removed from the database.
 %%  A kill operation takes precedence over other operations for the same
-%%  register (i.e. [{{x,0},kill},{{x,0},{tuple,5}}] means that the
+%%  register (i.e. [{{x,0},kill},{{x,0},{tuple,5,[]}}] means that the
 %%  the existing type information, if any, will be discarded, and the
-%%  the '{tuple,5}' information ignored.
+%%  the '{tuple,5,[]}' information ignored.
 %%
 %%  If NewInfo information is given and there exists information about
 %%  the register, the old and new type information will be merged.
-%%  For instance, {tuple,5} and {tuple,10} will be merged to produce
-%%  {tuple,10}.
+%%  For instance, {tuple,5,_} and {tuple,10,_} will be merged to produce
+%%  {tuple,10,_}.
 
 tdb_update(Uis0, Ts0) ->
     Uis1 = filter(fun ({{x,_},_Op}) -> true;
@@ -810,7 +845,8 @@ tdb_update(Uis0, Ts0) ->
 
 tdb_update1([{Key,kill}|Ops], [{K,_Old}|_]=Db) when Key < K ->
     tdb_update1(remove_key(Key, Ops), Db);
-tdb_update1([{Key,_New}=New|Ops], [{K,_Old}|_]=Db) when Key < K ->
+tdb_update1([{Key,Type}=New|Ops], [{K,_Old}|_]=Db) when Key < K ->
+    verify_type(Type),
     [New|tdb_update1(Ops, Db)];
 tdb_update1([{Key,kill}|Ops], [{Key,_}|Db]) ->
     tdb_update1(remove_key(Key, Ops), Db);
@@ -820,7 +856,8 @@ tdb_update1([{_,_}|_]=Ops, [Old|Db]) ->
     [Old|tdb_update1(Ops, Db)];
 tdb_update1([{Key,kill}|Ops], []) ->
     tdb_update1(remove_key(Key, Ops), []);
-tdb_update1([{_,_}=New|Ops], []) ->
+tdb_update1([{_,Type}=New|Ops], []) ->
+    verify_type(Type),
     [New|tdb_update1(Ops, [])];
 tdb_update1([], Db) -> Db.
 
@@ -855,6 +892,7 @@ merge_type_info(NewType, _) ->
     verify_type(NewType),
     NewType.
 
+verify_type({atom,_}) -> ok;
 verify_type(boolean) -> ok;
 verify_type(integer) -> ok;
 verify_type({integer,{Min,Max}})
diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index 6877141885..faff9940ec 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -1165,12 +1165,17 @@ assert_type(WantedType, Term, Vst) ->
 assert_type(Correct, Correct) -> ok;
 assert_type(float, {float,_}) -> ok;
 assert_type(tuple, {tuple,_}) -> ok;
+assert_type(tuple, {literal,Tuple}) when is_tuple(Tuple) -> ok;
 assert_type({tuple_element,I}, {tuple,[Sz]})
   when 1 =< I, I =< Sz ->
     ok;
 assert_type({tuple_element,I}, {tuple,Sz})
   when is_integer(Sz), 1 =< I, I =< Sz ->
     ok;
+assert_type({tuple_element,I}, {literal,Lit}) when I =< tuple_size(Lit) ->
+    ok;
+assert_type(cons, {literal,[_|_]}) ->
+    ok;
 assert_type(Needed, Actual) ->
     error({bad_type,{needed,Needed},{actual,Actual}}).
 
@@ -1549,8 +1554,12 @@ return_type_1(erlang, setelement, 3, Vst) ->
     Tuple = {x,1},
     TupleType =
 	case get_term_type(Tuple, Vst) of
-	    {tuple,_}=TT -> TT;
-	    _ -> {tuple,[0]}
+	    {tuple,_}=TT ->
+		TT;
+	    {literal,Lit} when is_tuple(Lit) ->
+		{tuple,tuple_size(Lit)};
+	    _ ->
+		{tuple,[0]}
 	end,
     case get_term_type({x,0}, Vst) of
 	{integer,[]} -> TupleType;
diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl
index 83b3650180..a3b0236134 100644
--- a/lib/compiler/src/v3_core.erl
+++ b/lib/compiler/src/v3_core.erl
@@ -510,16 +510,8 @@ unforce(_, Vs) -> Vs.
 
 exprs([E0|Es0], St0) ->
     {E1,Eps,St1} = expr(E0, St0),
-    case E1 of
-	#iprimop{name=#c_literal{val=match_fail}} ->
-	    %% Must discard the rest of the body, because it
-	    %% may refer to variables that have not been bound.
-	    %% Example: {ok={error,E}} = foo(), E.
-	    {Eps ++ [E1],St1};
-	_ ->
-	    {Es1,St2} = exprs(Es0, St1),
-	    {Eps ++ [E1] ++ Es1,St2}
-    end;
+    {Es1,St2} = exprs(Es0, St1),
+    {Eps ++ [E1] ++ Es1,St2};
 exprs([], St) -> {[],St}.
 
 %% expr(Expr, State) -> {Cexpr,[PreExp],State}.
@@ -689,14 +681,36 @@ expr({match,L,P0,E0}, St0) ->
     Fc = fail_clause([Fpat], Lanno, c_tuple([#c_literal{val=badmatch},Fpat])),
     case P2 of
 	nomatch ->
+	    %% The pattern will not match. We must take care here to
+	    %% bind all variables that the pattern would have bound
+	    %% so that subsequent expressions do not refer to unbound
+	    %% variables.
+	    %%
+	    %% As an example, this code:
+	    %%
+	    %%   [X] = {Y} = E,
+	    %%   X + Y.
+	    %%
+	    %% will be rewritten to:
+	    %%
+	    %%   error({badmatch,E}),
+	    %%   case E of
+	    %%      {[X],{Y}} ->
+	    %%        X + Y;
+	    %%      Other ->
+	    %%        error({badmatch,Other})
+	    %%   end.
+	    %%
 	    St6 = add_warning(L, nomatch, St5),
-	    {Expr,Eps3,St} = safe(E1, St6),
-	    Eps = Eps1 ++ Eps2 ++ Eps3,
+	    {Expr,Eps3,St7} = safe(E1, St6),
+	    SanPat0 = sanitize(P1),
+	    {SanPat,Eps4,St} = pattern(SanPat0, St7),
 	    Badmatch = c_tuple([#c_literal{val=badmatch},Expr]),
 	    Fail = #iprimop{anno=#a{anno=Lanno},
 			    name=#c_literal{val=match_fail},
 			    args=[Badmatch]},
-	    {Fail,Eps,St};
+	    Eps = Eps3 ++ Eps4 ++ [Fail],
+	    {#imatch{anno=#a{anno=Lanno},pat=SanPat,arg=Expr,fc=Fc},Eps,St};
 	Other when not is_atom(Other) ->
 	    {#imatch{anno=#a{anno=Lanno},pat=P2,arg=E2,fc=Fc},Eps1++Eps2,St5}
     end;
@@ -738,6 +752,32 @@ expr({op,L,Op,L0,R0}, St0) ->
 	    module=#c_literal{anno=LineAnno,val=erlang},
 	    name=#c_literal{anno=LineAnno,val=Op},args=As},Aps,St1}.
 
+
+%% sanitize(Pat) -> SanitizedPattern
+%%  Rewrite Pat so that it will be accepted by pattern/2 and will
+%%  bind the same variables as the original pattern.
+%%
+%%  Here is an example of a pattern that would cause a pattern/2
+%%  to generate a 'nomatch' exception:
+%%
+%%      #{k:=X,k:=Y} = [Z]
+%%
+%%  The sanitized pattern will look like:
+%%
+%%      {{X,Y},[Z]}
+
+sanitize({match,L,P1,P2}) ->
+    {tuple,L,[sanitize(P1),sanitize(P2)]};
+sanitize({cons,L,H,T}) ->
+    {cons,L,sanitize(H),sanitize(T)};
+sanitize({tuple,L,Ps0}) ->
+    Ps = [sanitize(P) || P <- Ps0],
+    {tuple,L,Ps};
+sanitize({map,L,Ps0}) ->
+    Ps = [sanitize(V) || {map_field_exact,_,_,V} <- Ps0],
+    {tuple,L,Ps};
+sanitize(P) -> P.
+
 make_bool_switch(L, E, V, T, F, #core{in_guard=true}) ->
     make_bool_switch_guard(L, E, V, T, F);
 make_bool_switch(L, E, V, T, F, #core{}) ->
diff --git a/lib/compiler/test/beam_bool_SUITE.erl b/lib/compiler/test/beam_bool_SUITE.erl
index 84d634e5ca..e585eaedb5 100644
--- a/lib/compiler/test/beam_bool_SUITE.erl
+++ b/lib/compiler/test/beam_bool_SUITE.erl
@@ -22,7 +22,8 @@
 -export([all/0,suite/0,groups/0,init_per_suite/1,end_per_suite/1,
 	 init_per_group/2,end_per_group/2,
 	 before_and_inside_if/1,
-	 scotland/1,y_registers/1]).
+	 scotland/1,y_registers/1,protected/1,
+	 maps/1]).
 
 suite() ->
     [{ct_hooks,[ts_install_cth]}].
@@ -35,7 +36,9 @@ groups() ->
     [{p,[parallel],
       [before_and_inside_if,
        scotland,
-       y_registers
+       y_registers,
+       protected,
+       maps
       ]}].
 
 init_per_suite(Config) ->
@@ -158,3 +161,37 @@ potter(Modes) ->
 		_ -> not_ok
 	    end,
     {Final,Raw}.
+
+protected(_Config) ->
+    {'EXIT',{if_clause,_}} = (catch photographs({1, surprise, true}, opinions)),
+
+    {{true}} = welcome({perfect, true}),
+    {'EXIT',{if_clause,_}} = (catch welcome({perfect, false})),
+    ok.
+
+photographs({_Violation, surprise, Deep}, opinions) ->
+    {if
+	 0; "here", Deep ->
+	     Deep = Deep
+     end}.
+
+welcome({perfect, Profit}) ->
+    if
+	Profit, Profit, Profit; 0 ->
+	    {id({Profit})}
+    end.
+
+maps(_Config) ->
+    ok = evidence(#{0 => 42}).
+
+%% Cover handling of put_map in in split_block_label_used/2.
+evidence(#{0 := Charge}) when 0; #{[] => Charge} == #{[] => 42} ->
+    ok.
+
+
+%%%
+%%% Common utilities.
+%%%
+
+id(I) ->
+    I.
diff --git a/lib/compiler/test/beam_reorder_SUITE.erl b/lib/compiler/test/beam_reorder_SUITE.erl
index 4b2262f65b..ff31f2d3bd 100644
--- a/lib/compiler/test/beam_reorder_SUITE.erl
+++ b/lib/compiler/test/beam_reorder_SUITE.erl
@@ -21,7 +21,7 @@
 
 -export([all/0,suite/0,groups/0,init_per_suite/1,end_per_suite/1,
 	 init_per_group/2,end_per_group/2,
-	 alloc/1]).
+	 alloc/1,confused_beam_validator/1]).
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
 
@@ -31,7 +31,8 @@ all() ->
 
 groups() ->
     [{p,[parallel],
-      [alloc
+      [alloc,
+       confused_beam_validator
       ]}].
 
 init_per_suite(Config) ->
@@ -65,5 +66,16 @@ alloc_b(_U1, _U2, R) ->
     _ = id(0),
     Res.
 
+confused_beam_validator(_Config) ->
+    {'EXIT',{{badmap,{any}},_}} = (catch efficient({any})),
+    ok.
+
+efficient({Var}=God) ->
+    id(God#{}),
+    catch
+	receive _ ->
+		Var
+	end.
+
 id(I) ->
     I.
diff --git a/lib/compiler/test/beam_type_SUITE.erl b/lib/compiler/test/beam_type_SUITE.erl
index 8d5c0190ed..69e2f1838d 100644
--- a/lib/compiler/test/beam_type_SUITE.erl
+++ b/lib/compiler/test/beam_type_SUITE.erl
@@ -21,7 +21,8 @@
 
 -export([all/0,suite/0,groups/0,init_per_suite/1,end_per_suite/1,
 	 init_per_group/2,end_per_group/2,
-	 integers/1,coverage/1,booleans/1]).
+	 integers/1,coverage/1,booleans/1,setelement/1,cons/1,
+	 tuple/1]).
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
 
@@ -33,7 +34,10 @@ groups() ->
     [{p,[parallel],
       [integers,
        coverage,
-       booleans
+       booleans,
+       setelement,
+       cons,
+       tuple
       ]}].
 
 init_per_suite(Config) ->
@@ -55,6 +59,8 @@ integers(_Config) ->
     a = do_integers_2(<<0:1>>),
     {'EXIT',{{case_clause,-1},_}} = (catch do_integers_2(<<1:1>>)),
 
+    college = do_integers_3(),
+
     ok.
 
 do_integers_1(B0) ->
@@ -71,6 +77,12 @@ do_integers_2(Bin) ->
 	1 -> b
     end.
 
+do_integers_3() ->
+    case try 0 after [] end of
+	0 -> college;
+	1 -> 0
+    end.
+
 coverage(_Config) ->
     {'EXIT',{badarith,_}} = (catch id(1) bsl 0.5),
     {'EXIT',{badarith,_}} = (catch id(2.0) bsl 2),
@@ -94,5 +106,25 @@ do_booleans(B) ->
 	no -> no
     end.
 
+setelement(_Config) ->
+    T0 = id({a,42}),
+    {a,_} = T0,
+    {b,_} = setelement(1, T0, b),
+    ok.
+
+cons(_Config) ->
+    [did] = cons(assigned, did),
+    ok.
+
+cons(assigned, Instrument) ->
+    [Instrument] = [did].
+
+tuple(_Config) ->
+    {'EXIT',{{badmatch,{necessary}},_}} = (catch do_tuple()),
+    ok.
+
+do_tuple() ->
+    {0, _} = {necessary}.
+
 id(I) ->
     I.
diff --git a/lib/compiler/test/beam_utils_SUITE.erl b/lib/compiler/test/beam_utils_SUITE.erl
index 6353ed3242..ae813d563b 100644
--- a/lib/compiler/test/beam_utils_SUITE.erl
+++ b/lib/compiler/test/beam_utils_SUITE.erl
@@ -23,7 +23,7 @@
 	 init_per_group/2,end_per_group/2,
 	 apply_fun/1,apply_mf/1,bs_init/1,bs_save/1,
 	 is_not_killed/1,is_not_used_at/1,
-	 select/1,y_catch/1,otp_8949_b/1,liveopt/1]).
+	 select/1,y_catch/1,otp_8949_b/1,liveopt/1,coverage/1]).
 -export([id/1]).
 
 suite() -> [{ct_hooks,[ts_install_cth]}].
@@ -43,7 +43,8 @@ groups() ->
        select,
        y_catch,
        otp_8949_b,
-       liveopt
+       liveopt,
+       coverage
       ]}].
 
 init_per_suite(Config) ->
@@ -268,6 +269,48 @@ liveopt_fun(Peer, Cause, Origin) ->
 	    void
     end.
 
+%% Thanks to QuickCheck.
+coverage(_Config) ->
+    42+7 = merchant([[],7,false]),
+
+    {'EXIT',{{try_clause,0},_}} = (catch resulting([0], stone)),
+    0.0 = resulting([true], stone),
+
+    {'EXIT',{if_clause,_}} = (catch clinic(false)),
+    {'EXIT',{{try_clause,"trials"},_}} = (catch clinic(true)),
+
+    {'EXIT',{function_clause,_}} = (catch town(overall, {{abc},alcohol})),
+
+    ok.
+
+%% Cover check_liveness/3.
+merchant([Merchant, Laws, Electric]) ->
+    id(42),
+    oklahoma([[] || 0 <- Merchant],
+	     if true; Electric -> Laws end) + 42.
+oklahoma([], Int) -> Int.
+
+town(overall, {{If}, Healing = alcohol})
+  when Healing#{[] => Healing}; include ->
+    [If || Healing <- awareness].
+
+%% Cover is_reg_used_at/3.
+resulting([Conservation], stone) ->
+    try 0 of
+	Conservation when Conservation -> Conservation;
+	_ when Conservation; 0 -> 0.0
+    after
+	Conservation
+    end.
+
+%% Cover is_reg_used_at_1/3.
+clinic(Damage) ->
+    if
+      Damage ->
+	  try "trials" of Damage when Damage -> Damage catch true -> [] end
+    end,
+    carefully.
+
 
 %% The identity function.
 id(I) -> I.
diff --git a/lib/compiler/test/match_SUITE.erl b/lib/compiler/test/match_SUITE.erl
index 92a9802cad..31402ac717 100644
--- a/lib/compiler/test/match_SUITE.erl
+++ b/lib/compiler/test/match_SUITE.erl
@@ -21,8 +21,8 @@
 
 -export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1, 
 	 init_per_group/2,end_per_group/2,
-	 pmatch/1,mixed/1,aliases/1,match_in_call/1,
-	 untuplify/1,shortcut_boolean/1,letify_guard/1,
+	 pmatch/1,mixed/1,aliases/1,non_matching_aliases/1,
+	 match_in_call/1,untuplify/1,shortcut_boolean/1,letify_guard/1,
 	 selectify/1,underscore/1,match_map/1,map_vars_used/1,
 	 coverage/1,grab_bag/1]).
 	 
@@ -36,7 +36,8 @@ all() ->
 
 groups() -> 
     [{p,[parallel],
-      [pmatch,mixed,aliases,match_in_call,untuplify,
+      [pmatch,mixed,aliases,non_matching_aliases,
+       match_in_call,untuplify,
        shortcut_boolean,letify_guard,selectify,
        underscore,match_map,map_vars_used,coverage,
        grab_bag]}].
@@ -143,16 +144,6 @@ aliases(Config) when is_list(Config) ->
     {a,b} = list_alias2([a,b]),
     {a,b} = list_alias3([a,b]),
 
-    %% Non-matching aliases.
-    none = mixed_aliases(<<42>>),
-    none = mixed_aliases([b]),
-    none = mixed_aliases([d]),
-    none = mixed_aliases({a,42}),
-    none = mixed_aliases(42),
-
-    %% Non-matching aliases.
-    {'EXIT',{{badmatch,42},_}} = (catch nomatch_alias(42)),
-
     ok.
 
 str_alias(V) ->
@@ -256,6 +247,33 @@ list_alias2([X,Y]=[a,b]) ->
 list_alias3([X,b]=[a,Y]) ->
     {X,Y}.
 
+non_matching_aliases(_Config) ->
+    none = mixed_aliases(<<42>>),
+    none = mixed_aliases([b]),
+    none = mixed_aliases([d]),
+    none = mixed_aliases({a,42}),
+    none = mixed_aliases(42),
+
+    {'EXIT',{{badmatch,42},_}} = (catch nomatch_alias(42)),
+    {'EXIT',{{badmatch,job},_}} = (catch entirely()),
+    {'EXIT',{{badmatch,associates},_}} = (catch printer()),
+    {'EXIT',{{badmatch,borogoves},_}} = (catch tench()),
+
+    put(perch, 0),
+    {'EXIT',{{badmatch,{spine,42}},_}} = (catch perch(42)),
+    1 = erase(perch),
+
+    put(salmon, 0),
+    {'EXIT',{{badmatch,mimsy},_}} = (catch salmon()),
+    1 = erase(salmon),
+
+    put(shark, 0),
+    {'EXIT',{{badmatch,_},_}} = (catch shark()),
+    1 = erase(shark),
+
+    {'EXIT',{{badmatch,_},_}} = (catch radio(research)),
+    ok.
+
 mixed_aliases(<<X:8>> = x) -> {a,X};
 mixed_aliases([b] = <<X:8>>) -> {b,X};
 mixed_aliases(<<X:8>> = {a,X}) -> {c,X};
@@ -266,6 +284,42 @@ nomatch_alias(I) ->
     {ok={A,B}} = id(I),
     {A,B}.
 
+entirely() ->
+    0(((Voice = true) = cool) = job),
+    [receive _ -> Voice end || banking <- printer].
+
+printer() ->
+    {[Indoor] = [] = associates},
+    [ireland || Indoor <- Indoor].
+
+tench() ->
+    E = begin
+	    [A] = [] = borogoves,
+	    A + 1
+	end,
+    E + 7 * A.
+
+perch(X) ->
+    begin
+	put(perch, get(perch)+1),
+	[A] = [] = {spine,X}
+    end.
+
+salmon() ->
+    {put(salmon, get(salmon)+1),#{key:=([A]=[])}=mimsy,exit(fail)},
+    A + 10.
+
+shark() ->
+    (hello = there) = (catch shark(put(shark, get(shark)+1), a = b)).
+
+shark(_, _) ->
+    ok.
+
+radio(research) ->
+    (connection = proof) =
+	(catch erlang:trace_pattern(catch mechanisms + assist,
+				    summary = mechanisms)).
+
 %% OTP-7018.
 
 match_in_call(Config) when is_list(Config) ->