Merge branch 'dev' into bmk/snmp/agent/multi_engine_id_for_traps/OTP-9119

7 files changed, 175 insertions, 155 deletions

diff --git a/lib/compiler/src/Makefile b/lib/compiler/src/Makefile
index 9da9253f5b..1238d113e1 100644
--- a/lib/compiler/src/Makefile
+++ b/lib/compiler/src/Makefile
@@ -1,7 +1,7 @@
 #
 # %CopyrightBegin%
 #
-# Copyright Ericsson AB 1996-2010. All Rights Reserved.
+# Copyright Ericsson AB 1996-2011. All Rights Reserved.
 #
 # The contents of this file are subject to the Erlang Public License,
 # Version 1.1, (the "License"); you may not use this file except in
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl
index 2a36fda1ea..5cc8252b99 100644
--- a/lib/compiler/src/beam_bsm.erl
+++ b/lib/compiler/src/beam_bsm.erl
@@ -651,10 +651,8 @@ add_warning(Term, Anno, Ws) ->
 warning_translate_label(Term, D) when is_tuple(Term) ->
     case element(1, Term) of
 	{label,F} ->
-	    case gb_trees:lookup(F, D) of
-		none -> Term;
-		{value,FA} -> setelement(1, Term, FA)
-	    end;
+	    FA = gb_trees:get(F, D),
+	    setelement(1, Term, FA);
 	_ -> Term
     end;
 warning_translate_label(Term, _) -> Term.
diff --git a/lib/compiler/src/beam_dead.erl b/lib/compiler/src/beam_dead.erl
index bb93110176..8e96569414 100644
--- a/lib/compiler/src/beam_dead.erl
+++ b/lib/compiler/src/beam_dead.erl
@@ -162,14 +162,11 @@ function({function,Name,Arity,CLabel,Is0}, Lc0) ->
 
 %% We must split the basic block when we encounter instructions with labels,
 %% such as catches and BIFs. All labels must be visible outside the blocks.
-%% Also remove empty blocks.
 
 split_blocks({function,Name,Arity,CLabel,Is0}) ->
     Is = split_blocks(Is0, []),
     {function,Name,Arity,CLabel,Is}.
 
-split_blocks([{block,[]}|Is], Acc) ->
-    split_blocks(Is, Acc);
 split_blocks([{block,Bl}|Is], Acc0) ->
     Acc = split_block(Bl, [], Acc0),
     split_blocks(Is, Acc);
@@ -246,30 +243,24 @@ forward([{select_val,Reg,_,{list,List}}=I|Is], D0, Lc, Acc) ->
     D = update_value_dict(List, Reg, D0),
     forward(Is, D, Lc, [I|Acc]);
 forward([{label,Lbl}=LblI,{block,[{set,[Dst],[Lit],move}|BlkIs]}=Blk|Is], D, Lc, Acc) ->
+    %% Assumption: The target labels in a select_val/3 instruction
+    %% cannot be reached in any other way than through the select_val/3
+    %% instruction (i.e. there can be no fallthrough to such label and
+    %% it cannot be referenced by, for example, a jump/1 instruction).
     Block = case gb_trees:lookup({Lbl,Dst}, D) of
-		{value,Lit} ->
-		    %% The move instruction seems to be redundant, but also make
-		    %% sure that the instruction preceeding the label
-		    %% cannot fall through to the move instruction.
-		    case is_unreachable_after(Acc) of
-			false -> Blk;	  %Must keep move instruction.
-			true ->  {block,BlkIs}	%Safe to remove move instruction.
-		    end;
-		_ -> Blk		       %Keep move instruction.
+		{value,Lit} -> {block,BlkIs}; %Safe to remove move instruction.
+		_ -> Blk		      %Must keep move instruction.
 	    end,
     forward([Block|Is], D, Lc, [LblI|Acc]);
 forward([{label,Lbl}=LblI|[{move,Lit,Dst}|Is1]=Is0], D, Lc, Acc) ->
+    %% Assumption: The target labels in a select_val/3 instruction
+    %% cannot be reached in any other way than through the select_val/3
+    %% instruction (i.e. there can be no fallthrough to such label and
+    %% it cannot be referenced by, for example, a jump/1 instruction).
     Is = case gb_trees:lookup({Lbl,Dst}, D) of
-	     {value,Lit} ->
-		 %% The move instruction seems to be redundant, but also make
-		 %% sure that the instruction preceeding the label
-		 %% cannot fall through to the move instruction.
-		 case is_unreachable_after(Acc) of
-		     false -> Is0;	  %Must keep move instruction.
-		     true -> Is1     %Safe to remove move instruction.
-		  end;
-	     _ -> Is0		       %Keep move instruction.
-	  end,
+	     {value,Lit} -> Is1;     %Safe to remove move instruction.
+	     _ -> Is0		     %Keep move instruction.
+	 end,
     forward(Is, D, Lc, [LblI|Acc]);
 forward([{test,is_eq_exact,_,[Dst,Src]}=I,
 	 {block,[{set,[Dst],[Src],move}|Bl]}|Is], D, Lc, Acc) ->
@@ -299,16 +290,12 @@ update_value_dict([Lit,{f,Lbl}|T], Reg, D0) ->
     Key = {Lbl,Reg},
     D = case gb_trees:lookup(Key, D0) of
 	    none -> gb_trees:insert(Key, Lit, D0); %New.
-	    {value,Lit} -> D0;			%Already correct.
 	    {value,inconsistent} -> D0;		%Inconsistent.
 	    {value,_} -> gb_trees:update(Key, inconsistent, D0)
 	end,
     update_value_dict(T, Reg, D);
 update_value_dict([], _, D) -> D.
 
-is_unreachable_after([I|_]) ->
-    beam_jump:is_unreachable_after(I).
-
 %%%
 %%% Scan instructions in reverse execution order and remove dead code.
 %%%
@@ -602,16 +589,11 @@ count_bits_matched([{test,_,_,_}|Is], SavePoint, Bits) ->
 count_bits_matched([{bs_save2,Reg,SavePoint}|_], {Reg,SavePoint}, Bits) ->
     %% The save point we are looking for - we are done.
     Bits;
-count_bits_matched([{bs_save2,_,_}|Is], SavePoint, Bits) ->
-    %% Another save point - keep counting.
-    count_bits_matched(Is, SavePoint, Bits);
 count_bits_matched([_|_], _, Bits) -> Bits.
 
 shortcut_bs_pos_used(To, Reg, D) ->
     shortcut_bs_pos_used_1(beam_utils:code_at(To, D), Reg, D).
 
-shortcut_bs_pos_used_1([{bs_restore2,Reg,_}|_], Reg, _) ->
-    false;
 shortcut_bs_pos_used_1([{bs_context_to_binary,Reg}|_], Reg, _) ->
     false;
 shortcut_bs_pos_used_1(Is, Reg, D) ->
diff --git a/lib/compiler/src/beam_dict.erl b/lib/compiler/src/beam_dict.erl
index a1f994dfbd..c50ed28aa9 100644
--- a/lib/compiler/src/beam_dict.erl
+++ b/lib/compiler/src/beam_dict.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1998-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2011. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -36,7 +36,6 @@
 	 strings = <<>>		    :: binary(),	%String pool
 	 lambdas = [],				%[{...}]
 	 literals = dict:new()	    :: dict(),	%Format: {Literal,Number}
-	 next_atom = 1		    :: pos_integer(),
 	 next_import = 0	    :: non_neg_integer(),
 	 string_offset = 0	    :: non_neg_integer(),
 	 next_literal = 0	    :: non_neg_integer(),
@@ -66,13 +65,14 @@ highest_opcode(#asm{highest_opcode=Op}) -> Op.
 %%    atom(Atom, Dict) -> {Index,Dict'}
 -spec atom(atom(), bdict()) -> {pos_integer(), bdict()}.
 
-atom(Atom, #asm{atoms=Atoms0,next_atom=NextIndex}=Dict) when is_atom(Atom) ->
+atom(Atom, #asm{atoms=Atoms0}=Dict) when is_atom(Atom) ->
     case gb_trees:lookup(Atom, Atoms0) of
 	{value,Index} ->
 	    {Index,Dict};
 	none ->
+	    NextIndex = gb_trees:size(Atoms0) + 1,
 	    Atoms = gb_trees:insert(Atom, NextIndex, Atoms0),
-	    {NextIndex,Dict#asm{atoms=Atoms,next_atom=NextIndex+1}}
+	    {NextIndex,Dict#asm{atoms=Atoms}}
     end.
 
 %% Remembers an exported function.
@@ -139,7 +139,7 @@ lambda(Lbl, Index, OldUniq, NumFree, #asm{lambdas=Lambdas0}=Dict) ->
     Lambdas = [{Lbl,{OldIndex,Lbl,Index,NumFree,OldUniq}}|Lambdas0],
     {OldIndex,Dict#asm{lambdas=Lambdas}}.
 
-%% Returns the index for a literal (adding it to the atom table if necessary).
+%% Returns the index for a literal (adding it to the literal table if necessary).
 %%    literal(Literal, Dict) -> {Index,Dict'}
 -spec literal(term(), bdict()) -> {non_neg_integer(), bdict()}.
 
@@ -156,14 +156,15 @@ literal(Lit, #asm{literals=Tab0,next_literal=NextIndex}=Dict) ->
 %%    atom_table(Dict) -> {LastIndex,[Length,AtomString...]}
 -spec atom_table(bdict()) -> {non_neg_integer(), [[non_neg_integer(),...]]}.
 
-atom_table(#asm{atoms=Atoms,next_atom=NumAtoms}) ->
+atom_table(#asm{atoms=Atoms}) ->
+    NumAtoms = gb_trees:size(Atoms),
     Sorted = lists:keysort(2, gb_trees:to_list(Atoms)),
     Fun = fun({A,_}) ->
 		  L = atom_to_list(A),
 		  [length(L)|L]
 	  end,
     AtomTab = lists:map(Fun, Sorted),
-    {NumAtoms-1,AtomTab}.
+    {NumAtoms,AtomTab}.
 
 %% Returns the table of local functions.
 %%    local_table(Dict) -> {NumLocals, [{Function, Arity, Label}...]}
diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl
index 96015fbe58..9360556e00 100644
--- a/lib/compiler/src/sys_core_fold.erl
+++ b/lib/compiler/src/sys_core_fold.erl
@@ -460,7 +460,8 @@ eval_binary(#c_binary{anno=Anno,segments=Ss}=Bin) ->
 	    Bin;
 	  throw:{badarg,Warning} ->
 	    add_warning(Bin, Warning),
-	    #c_call{module=#c_literal{val=erlang},
+	    #c_call{anno=Anno,
+		    module=#c_literal{val=erlang},
 		    name=#c_literal{val=error},
 		    args=[#c_literal{val=badarg}]}
     end.
@@ -658,36 +659,34 @@ call_0(Call, M, N, As0, Sub) ->
 %% We inline some very common higher order list operations.
 %% We use the same evaluation order as the library function.
 
-call_1(_Call, lists, all, [Arg1,Arg2], Sub) ->
+call_1(#c_call{anno=Anno}, lists, all, [Arg1,Arg2], Sub) ->
     Loop = #c_var{name={'lists^all',1}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
     X = #c_var{name='X'},
     Err1 = #c_tuple{es=[#c_literal{val='case_clause'}, X]},
     CC1 = #c_clause{pats=[#c_literal{val=true}], guard=#c_literal{val=true},
-		    body=#c_apply{op=Loop, args=[Xs]}},
+		    body=#c_apply{anno=Anno, op=Loop, args=[Xs]}},
     CC2 = #c_clause{pats=[#c_literal{val=false}], guard=#c_literal{val=true},
 		    body=#c_literal{val=false}},
     CC3 = #c_clause{pats=[X], guard=#c_literal{val=true},
-		    body=#c_primop{name=#c_literal{val='match_fail'},
-				   args=[Err1]}},
+		    body=match_fail(Anno, Err1)},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=#c_case{arg=#c_apply{op=F, args=[X]},
+		   body=#c_case{arg=#c_apply{anno=Anno, op=F, args=[X]},
 				clauses = [CC1, CC2, CC3]}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
 		   body=#c_literal{val=true}},
     Err2 = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err2]}},
+		   body=match_fail(Anno, Err2)},
     Fun = #c_fun{vars=[Xs],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, L], arg=#c_values{es=[Arg1, Arg2]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L]}}},
 	 Sub);
-call_1(_Call, lists, any, [Arg1,Arg2], Sub) ->
+call_1(#c_call{anno=Anno}, lists, any, [Arg1,Arg2], Sub) ->
     Loop = #c_var{name={'lists^any',1}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
@@ -696,72 +695,71 @@ call_1(_Call, lists, any, [Arg1,Arg2], Sub) ->
     CC1 = #c_clause{pats=[#c_literal{val=true}], guard=#c_literal{val=true},
 		    body=#c_literal{val=true}},
     CC2 = #c_clause{pats=[#c_literal{val=false}], guard=#c_literal{val=true},
-		    body=#c_apply{op=Loop, args=[Xs]}},
+		    body=#c_apply{anno=Anno, op=Loop, args=[Xs]}},
     CC3 = #c_clause{pats=[X], guard=#c_literal{val=true},
-		    body=#c_primop{name=#c_literal{val='match_fail'},
-				   args=[Err1]}},
+		    body=match_fail(Anno, Err1)},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=#c_case{arg=#c_apply{op=F, args=[X]},
+		   body=#c_case{arg=#c_apply{anno=Anno, op=F, args=[X]},
 				clauses = [CC1, CC2, CC3]}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
 		   body=#c_literal{val=false}},
     Err2 = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err2]}},
+		   body=match_fail(Anno, Err2)},
     Fun = #c_fun{vars=[Xs],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, L], arg=#c_values{es=[Arg1, Arg2]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L]}}},
 	 Sub);
-call_1(_Call, lists, foreach, [Arg1,Arg2], Sub) ->
+call_1(#c_call{anno=Anno}, lists, foreach, [Arg1,Arg2], Sub) ->
     Loop = #c_var{name={'lists^foreach',1}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
     X = #c_var{name='X'},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=#c_seq{arg=#c_apply{op=F, args=[X]},
-			       body=#c_apply{op=Loop, args=[Xs]}}},
+		   body=#c_seq{arg=#c_apply{anno=Anno, op=F, args=[X]},
+			       body=#c_apply{anno=Anno, op=Loop, args=[Xs]}}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
 		   body=#c_literal{val=ok}},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, L], arg=#c_values{es=[Arg1, Arg2]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L]}}},
 	 Sub);
-call_1(_Call, lists, map, [Arg1,Arg2], Sub) ->
+call_1(#c_call{anno=Anno}, lists, map, [Arg1,Arg2], Sub) ->
     Loop = #c_var{name={'lists^map',1}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
     X = #c_var{name='X'},
     H = #c_var{name='H'},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=#c_let{vars=[H], arg=#c_apply{op=F, args=[X]},
+		   body=#c_let{vars=[H], arg=#c_apply{anno=Anno,
+						      op=F,
+						      args=[X]},
 			       body=#c_cons{hd=H,
-					    tl=#c_apply{op=Loop,
+					    tl=#c_apply{anno=Anno,
+							op=Loop,
 							args=[Xs]}}}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
 		   body=#c_literal{val=[]}},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, L], arg=#c_values{es=[Arg1, Arg2]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L]}}},
 	 Sub);
-call_1(_Call, lists, flatmap, [Arg1,Arg2], Sub) ->
+call_1(#c_call{anno=Anno}, lists, flatmap, [Arg1,Arg2], Sub) ->
     Loop = #c_var{name={'lists^flatmap',1}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
@@ -769,26 +767,27 @@ call_1(_Call, lists, flatmap, [Arg1,Arg2], Sub) ->
     H = #c_var{name='H'},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
 		   body=#c_let{vars=[H],
-			       arg=#c_apply{op=F, args=[X]},
-			       body=#c_call{module=#c_literal{val=erlang},
+			       arg=#c_apply{anno=Anno, op=F, args=[X]},
+			       body=#c_call{anno=Anno,
+					    module=#c_literal{val=erlang},
 					    name=#c_literal{val='++'},
 					    args=[H,
-						  #c_apply{op=Loop,
+						  #c_apply{anno=Anno,
+							   op=Loop,
 							   args=[Xs]}]}}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
 		   body=#c_literal{val=[]}},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, L], arg=#c_values{es=[Arg1, Arg2]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L]}}},
 	 Sub);
-call_1(_Call, lists, filter, [Arg1,Arg2], Sub) ->
+call_1(#c_call{anno=Anno}, lists, filter, [Arg1,Arg2], Sub) ->
     Loop = #c_var{name={'lists^filter',1}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
@@ -800,72 +799,75 @@ call_1(_Call, lists, filter, [Arg1,Arg2], Sub) ->
     CC2 = #c_clause{pats=[#c_literal{val=false}], guard=#c_literal{val=true},
 		    body=Xs},
     CC3 = #c_clause{pats=[X], guard=#c_literal{val=true},
-		    body=#c_primop{name=#c_literal{val='match_fail'},
-				   args=[Err1]}},
+		    body=match_fail(Anno, Err1)},
     Case = #c_case{arg=B, clauses = [CC1, CC2, CC3]},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
 		   body=#c_let{vars=[B],
-			       arg=#c_apply{op=F, args=[X]},
+			       arg=#c_apply{anno=Anno, op=F, args=[X]},
 			       body=#c_let{vars=[Xs],
-					   arg=#c_apply{op=Loop,
+					   arg=#c_apply{anno=Anno,
+							op=Loop,
 							args=[Xs]},
 					   body=Case}}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true},
 		   body=#c_literal{val=[]}},
     Err2 = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err2]}},
+		   body=match_fail(Anno, Err2)},
     Fun = #c_fun{vars=[Xs],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, L], arg=#c_values{es=[Arg1, Arg2]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L]}}},
     Sub);
-call_1(_Call, lists, foldl, [Arg1,Arg2,Arg3], Sub) ->
+call_1(#c_call{anno=Anno}, lists, foldl, [Arg1,Arg2,Arg3], Sub) ->
     Loop = #c_var{name={'lists^foldl',2}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
     X = #c_var{name='X'},
     A = #c_var{name='A'},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=#c_apply{op=Loop,
-				 args=[Xs, #c_apply{op=F, args=[X, A]}]}},
+		   body=#c_apply{anno=Anno,
+				 op=Loop,
+				 args=[Xs, #c_apply{anno=Anno,
+						    op=F,
+						    args=[X, A]}]}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true}, body=A},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs, A],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, A, L], arg=#c_values{es=[Arg1, Arg2, Arg3]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L, A]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L, A]}}},
 	 Sub);
-call_1(_Call, lists, foldr, [Arg1,Arg2,Arg3], Sub) ->
+call_1(#c_call{anno=Anno}, lists, foldr, [Arg1,Arg2,Arg3], Sub) ->
     Loop = #c_var{name={'lists^foldr',2}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
     X = #c_var{name='X'},
     A = #c_var{name='A'},
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=#c_apply{op=F, args=[X, #c_apply{op=Loop,
-							 args=[Xs, A]}]}},
+		   body=#c_apply{anno=Anno,
+				 op=F,
+				 args=[X, #c_apply{anno=Anno,
+						   op=Loop,
+						   args=[Xs, A]}]}},
     C2 = #c_clause{pats=[#c_literal{val=[]}], guard=#c_literal{val=true}, body=A},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs, A],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, A, L], arg=#c_values{es=[Arg1, Arg2, Arg3]},
 		body=#c_letrec{defs=[{Loop,Fun}],
-			       body=#c_apply{op=Loop, args=[L, A]}}},
+			       body=#c_apply{anno=Anno, op=Loop, args=[L, A]}}},
 	 Sub);
-call_1(_Call, lists, mapfoldl, [Arg1,Arg2,Arg3], Sub) ->
+call_1(#c_call{anno=Anno}, lists, mapfoldl, [Arg1,Arg2,Arg3], Sub) ->
     Loop = #c_var{name={'lists^mapfoldl',2}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
@@ -876,15 +878,16 @@ call_1(_Call, lists, mapfoldl, [Arg1,Arg2,Arg3], Sub) ->
 		C1 = #c_clause{pats=[P], guard=#c_literal{val=true}, body=E},
 		Err = #c_tuple{es=[#c_literal{val='badmatch'}, X]},
 		C2 = #c_clause{pats=[X], guard=#c_literal{val=true},
-			       body=#c_primop{name=#c_literal{val='match_fail'},
-					      args=[Err]}},
+			       body=match_fail(Anno, Err)},
 		#c_case{arg=A, clauses=[C1, C2]}
 	end,
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
-		   body=Match(#c_apply{op=F, args=[X, Avar]},
+		   body=Match(#c_apply{anno=Anno, op=F, args=[X, Avar]},
 			      #c_tuple{es=[X, Avar]},
 %%% Tuple passing version
-			      Match(#c_apply{op=Loop, args=[Xs, Avar]},
+			      Match(#c_apply{anno=Anno,
+					     op=Loop,
+					     args=[Xs, Avar]},
 				    #c_tuple{es=[Xs, Avar]},
 				    #c_tuple{es=[#c_cons{hd=X, tl=Xs}, Avar]})
 %%% Multiple-value version
@@ -902,22 +905,23 @@ call_1(_Call, lists, mapfoldl, [Arg1,Arg2,Arg3], Sub) ->
 %%% 		   body=#c_values{es=[#c_literal{val=[]}, A]}},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs, Avar],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, Avar, L], arg=#c_values{es=[Arg1, Arg2, Arg3]},
 		body=#c_letrec{defs=[{Loop,Fun}],
 %%% Tuple passing version
-			       body=#c_apply{op=Loop, args=[L, Avar]}}},
+			       body=#c_apply{anno=Anno,
+					     op=Loop,
+					     args=[L, Avar]}}},
 %%% Multiple-value version
 %%% 			       body=#c_let{vars=[Xs, A],
 %%% 					   arg=#c_apply{op=Loop,
 %%% 							args=[L, A]},
 %%% 					   body=#c_tuple{es=[Xs, A]}}}},
 	 Sub);
-call_1(_Call, lists, mapfoldr, [Arg1,Arg2,Arg3], Sub) ->
+call_1(#c_call{anno=Anno}, lists, mapfoldr, [Arg1,Arg2,Arg3], Sub) ->
     Loop = #c_var{name={'lists^mapfoldr',2}},
     F = #c_var{name='F'},
     Xs = #c_var{name='Xs'},
@@ -928,15 +932,16 @@ call_1(_Call, lists, mapfoldr, [Arg1,Arg2,Arg3], Sub) ->
 		C1 = #c_clause{pats=[P], guard=#c_literal{val=true}, body=E},
 		Err = #c_tuple{es=[#c_literal{val='badmatch'}, X]},
 		C2 = #c_clause{pats=[X], guard=#c_literal{val=true},
-			       body=#c_primop{name=#c_literal{val='match_fail'},
-					      args=[Err]}},
+			       body=match_fail(Anno, Err)},
 		#c_case{arg=A, clauses=[C1, C2]}
 	end,
     C1 = #c_clause{pats=[#c_cons{hd=X, tl=Xs}], guard=#c_literal{val=true},
 %%% Tuple passing version
-		   body=Match(#c_apply{op=Loop, args=[Xs, Avar]},
+		   body=Match(#c_apply{anno=Anno,
+				       op=Loop,
+				       args=[Xs, Avar]},
 			      #c_tuple{es=[Xs, Avar]},
-			      Match(#c_apply{op=F, args=[X, Avar]},
+			      Match(#c_apply{anno=Anno, op=F, args=[X, Avar]},
 				    #c_tuple{es=[X, Avar]},
 				    #c_tuple{es=[#c_cons{hd=X, tl=Xs}, Avar]}))
 %%% Multiple-value version
@@ -955,15 +960,16 @@ call_1(_Call, lists, mapfoldr, [Arg1,Arg2,Arg3], Sub) ->
 %%% 		   body=#c_values{es=[#c_literal{val=[]}, A]}},
     Err = #c_tuple{es=[#c_literal{val='function_clause'}, Xs]},
     C3 = #c_clause{pats=[Xs], guard=#c_literal{val=true},
-		   body=#c_primop{name=#c_literal{val='match_fail'},
-				  args=[Err]}},
+		   body=match_fail(Anno, Err)},
     Fun = #c_fun{vars=[Xs, Avar],
 		 body=#c_case{arg=Xs, clauses=[C1, C2, C3]}},
     L = #c_var{name='L'},
     expr(#c_let{vars=[F, Avar, L], arg=#c_values{es=[Arg1, Arg2, Arg3]},
 		body=#c_letrec{defs=[{Loop,Fun}],
 %%% Tuple passing version
- 			       body=#c_apply{op=Loop, args=[L, Avar]}}},
+			       body=#c_apply{anno=Anno,
+					     op=Loop,
+					     args=[L, Avar]}}},
 %%% Multiple-value version
 %%% 			       body=#c_let{vars=[Xs, A],
 %%% 					   arg=#c_apply{op=Loop,
@@ -973,6 +979,11 @@ call_1(_Call, lists, mapfoldr, [Arg1,Arg2,Arg3], Sub) ->
 call_1(#c_call{module=M, name=N}=Call, _, _, As, Sub) ->
     call_0(Call, M, N, As, Sub).
 
+match_fail(Anno, Arg) ->
+    #c_primop{anno=Anno,
+	      name=#c_literal{val='match_fail'},
+	      args=[Arg]}.
+
 %% fold_call(Call, Mod, Name, Args, Sub) -> Expr.
 %%  Try to safely evaluate the call.  Just try to evaluate arguments,
 %%  do the call and convert return values to literals.  If this
@@ -1280,9 +1291,9 @@ eval_setelement_2(Pos, [H|T], NewVal) when Pos > 1 ->
 %%
 eval_failure(Call, Reason) ->
     add_warning(Call, {eval_failure,Reason}),
-    #c_call{module=#c_literal{val=erlang},
-	    name=#c_literal{val=error},
-	    args=[#c_literal{val=Reason}]}.
+    Call#c_call{module=#c_literal{val=erlang},
+		name=#c_literal{val=error},
+		args=[#c_literal{val=Reason}]}.
 
 %% simplify_apply(Call0, Mod, Func, Args) -> Call
 %%  Simplify an apply/3 to a call if the number of arguments
@@ -1742,23 +1753,24 @@ opt_bool_clauses([_|_], _, _) ->
 
 opt_bool_not(#c_case{arg=Arg,clauses=Cs0}=Case0) ->
     case Arg of
-	#c_call{module=#c_literal{val=erlang},
+	#c_call{anno=Anno,module=#c_literal{val=erlang},
  		name=#c_literal{val='not'},
  		args=[Expr]} ->
-	    Cs = opt_bool_not(Expr, Cs0),
+	    Cs = opt_bool_not(Anno, Expr, Cs0),
 	    Case = Case0#c_case{arg=Expr,clauses=Cs},
 	    opt_bool_not(Case);
 	_ ->
 	    opt_bool_case_redundant(Case0)
     end.
 
-opt_bool_not(Expr, Cs) ->
+opt_bool_not(Anno, Expr, Cs) ->
     Tail = case is_bool_expr(Expr) of
 	       false ->
 		   [#c_clause{anno=[compiler_generated],
 			      pats=[#c_var{name=cor_variable}],
 			      guard=#c_literal{val=true},
-			      body=#c_call{module=#c_literal{val=erlang},
+			      body=#c_call{anno=Anno,
+					   module=#c_literal{val=erlang},
 					   name=#c_literal{val=error},
 					   args=[#c_literal{val=badarg}]}}];
 	       true -> []
@@ -1957,13 +1969,25 @@ case_tuple_pat([#c_tuple{es=Ps}], Arity) when length(Ps) =:= Arity ->
 case_tuple_pat([#c_literal{val=T}], Arity) when tuple_size(T) =:= Arity ->
     Ps = [#c_literal{val=E} || E <- tuple_to_list(T)],
     {ok,Ps,[]};
-case_tuple_pat([#c_var{anno=A}=V], Arity) ->
-    Vars = make_vars(A, 1, Arity),
-    {ok,Vars,[{V,#c_tuple{es=Vars}}]};
+case_tuple_pat([#c_var{anno=Anno0}=V], Arity) ->
+    Vars = make_vars(Anno0, 1, Arity),
+
+    %% If the entire case statement is evaluated in an effect
+    %% context (e.g. "case {A,B} of ... end, ok"), there will
+    %% be a warning that a term is constructed but never used.
+    %% To avoid that warning, we must annotate the tuple as
+    %% compiler generated.
+
+    Anno = [compiler_generated|Anno0],
+    {ok,Vars,[{V,#c_tuple{anno=Anno,es=Vars}}]};
 case_tuple_pat([#c_alias{var=V,pat=P}], Arity) ->
     case case_tuple_pat([P], Arity) of
-	{ok,Ps,Avs} -> {ok,Ps,[{V,#c_tuple{es=unalias_pat_list(Ps)}}|Avs]};
-	error -> error
+	{ok,Ps,Avs} ->
+	    Anno0 = core_lib:get_anno(P),
+	    Anno = [compiler_generated|Anno0],
+	    {ok,Ps,[{V,#c_tuple{anno=Anno,es=unalias_pat_list(Ps)}}|Avs]};
+	error ->
+	    error
     end;
 case_tuple_pat(_, _) -> error.
 
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index f24a46c5a9..55e3c58d2a 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1999-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1999-2011. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl
index 2da24b2908..e1a593fffa 100644
--- a/lib/compiler/src/v3_core.erl
+++ b/lib/compiler/src/v3_core.erl
@@ -1820,7 +1820,21 @@ upattern_list([], _, St) -> {[],[],[],[],St}.
 %% upat_bin([Pat], [KnownVar], State) ->
 %%                        {[Pat],[GuardTest],[NewVar],[UsedVar],State}.
 upat_bin(Es0, Ks, St0) ->
-  upat_bin(Es0, Ks, [], St0).
+    {Es1,Pg,Pv,Pu0,St1} = upat_bin(Es0, Ks, [], St0),
+
+    %% In a clause such as <<Sz:8,V:Sz>> in a function head, Sz will both
+    %% be new and used; a situation that is not handled properly by
+    %% uclause/4.  (Basically, since Sz occurs in two sets that are
+    %% subtracted from each other, Sz will not be added to the list of
+    %% known variables and will seem to be new the next time it is
+    %% used in a match.)
+    %%   Since the variable Sz really is new (it does not use a
+    %% value bound prior to the binary matching), Sz should only be
+    %% included in the set of new variables. Thus we should take it
+    %% out of the set of used variables.
+
+    Pu1 = subtract(Pu0, intersection(Pv, Pu0)),
+    {Es1,Pg,Pv,Pu1,St1}.
 
 %% upat_bin([Pat], [KnownVar], [LocalVar], State) ->
 %%                        {[Pat],[GuardTest],[NewVar],[UsedVar],State}.
@@ -1832,35 +1846,36 @@ upat_bin([], _, _, St) -> {[],[],[],[],St}.
 
 
 %% upat_element(Segment, [KnownVar], [LocalVar], State) ->
-%%                        {Segment,[GuardTest],[NewVar],[UsedVar],[LocalVar],State}
-upat_element(#c_bitstr{val=H0,size=Sz}=Seg, Ks, Bs, St0) ->
-  {H1,Hg,Hv,[],St1} = upattern(H0, Ks, St0),
-  Bs1 = case H0 of
-	  #c_var{name=Hname} ->
-	    case H1 of
+%%        {Segment,[GuardTest],[NewVar],[UsedVar],[LocalVar],State}
+upat_element(#c_bitstr{val=H0,size=Sz0}=Seg, Ks, Bs0, St0) ->
+    {H1,Hg,Hv,[],St1} = upattern(H0, Ks, St0),
+    Bs1 = case H0 of
 	      #c_var{name=Hname} ->
-		Bs;
-	      #c_var{name=Other} ->
-		[{Hname, Other}|Bs]
-	    end;
-	  _ ->
-	    Bs
-	end,
-  {Sz1, Us} = case Sz of
-		  #c_var{name=Vname} -> 
-		    rename_bitstr_size(Vname, Bs);
-		  _Other -> {Sz, []}
-		end,
-  {Seg#c_bitstr{val=H1, size=Sz1},Hg,Hv,Us,Bs1,St1}.
-
-rename_bitstr_size(V, [{V, N}|_]) ->
-   New = #c_var{name=N},
-  {New, [N]};
+		  case H1 of
+		      #c_var{name=Hname} ->
+			  Bs0;
+		      #c_var{name=Other} ->
+			  [{Hname,Other}|Bs0]
+		  end;
+	      _ ->
+		  Bs0
+	  end,
+    {Sz1,Us} = case Sz0 of
+		   #c_var{name=Vname} -> 
+		       rename_bitstr_size(Vname, Bs0);
+		   _Other ->
+		       {Sz0,[]}
+	       end,
+    {Seg#c_bitstr{val=H1,size=Sz1},Hg,Hv,Us,Bs1,St1}.
+
+rename_bitstr_size(V, [{V,N}|_]) ->
+    New = #c_var{name=N},
+    {New,[N]};
 rename_bitstr_size(V, [_|Rest]) ->
-  rename_bitstr_size(V, Rest);
+    rename_bitstr_size(V, Rest);
 rename_bitstr_size(V, []) ->
-  Old = #c_var{name=V},
-  {Old, [V]}.
+    Old = #c_var{name=V},
+    {Old,[V]}.
  
 used_in_any(Les) ->
     foldl(fun (Le, Ns) -> union((get_anno(Le))#a.us, Ns) end,