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-rw-r--r--erts/doc/src/erlang.xml9
-rw-r--r--erts/emulator/test/code_SUITE.erl28
-rw-r--r--erts/emulator/test/code_SUITE_data/fun_confusion.erl31
-rw-r--r--lib/compiler/src/beam_asm.erl52
-rw-r--r--lib/compiler/src/beam_dict.erl13
-rw-r--r--lib/tools/test/cover_SUITE.erl31
-rw-r--r--lib/tools/test/cover_SUITE_data/otp_6115/f1.erl11
7 files changed, 123 insertions, 52 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 45b66a4909..5d7ff7613b 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -1196,11 +1196,16 @@ true
</item>
<tag><c>{new_uniq, Uniq}</c></tag>
<item>
- <p><c>Uniq</c> (a binary) is a unique value for this fun.</p>
+ <p><c>Uniq</c> (a binary) is a unique value for this fun.
+ It is calculated from the compiled code for the entire module.</p>
</item>
<tag><c>{uniq, Uniq}</c></tag>
<item>
- <p><c>Uniq</c> (an integer) is a unique value for this fun.</p>
+ <p><c>Uniq</c> (an integer) is a unique value for this fun.
+ Starting in the R15 release, this integer is calculated from
+ the compiled code for the entire module. Before R15, this
+ integer was based on only the body of the fun.
+ </p>
</item>
</taglist>
</desc>
diff --git a/erts/emulator/test/code_SUITE.erl b/erts/emulator/test/code_SUITE.erl
index 29cbdedd17..6bce448842 100644
--- a/erts/emulator/test/code_SUITE.erl
+++ b/erts/emulator/test/code_SUITE.erl
@@ -25,7 +25,7 @@
t_check_process_code_ets/1,
external_fun/1,get_chunk/1,module_md5/1,make_stub/1,
make_stub_many_funs/1,constant_pools/1,
- false_dependency/1,coverage/1]).
+ false_dependency/1,coverage/1,fun_confusion/1]).
-include_lib("test_server/include/test_server.hrl").
@@ -35,7 +35,7 @@ all() ->
[new_binary_types, t_check_process_code,
t_check_process_code_ets, t_check_old_code, external_fun, get_chunk,
module_md5, make_stub, make_stub_many_funs,
- constant_pools, false_dependency, coverage].
+ constant_pools, false_dependency, coverage, fun_confusion].
groups() ->
[].
@@ -555,6 +555,30 @@ coverage(Config) when is_list(Config) ->
?line {'EXIT',{badarg,_}} = (catch erlang:module_loaded(42)),
ok.
+fun_confusion(Config) when is_list(Config) ->
+ Data = ?config(data_dir, Config),
+ Src = filename:join(Data, "fun_confusion"),
+ Mod = fun_confusion,
+
+ %% Load first version of module.
+ compile_load(Mod, Src, 1),
+ F1 = Mod:f(),
+ 1 = F1(),
+
+ %% Load second version of module.
+ compile_load(Mod, Src, 2),
+ F2 = Mod:f(),
+
+ %% F1 should refer to the old code, not the newly loaded code.
+ 1 = F1(),
+ 2 = F2(),
+ ok.
+
+compile_load(Mod, Src, Ver) ->
+ {ok,Mod,Code1} = compile:file(Src, [binary,{d,version,Ver}]),
+ {module,Mod} = code:load_binary(Mod, "fun_confusion.beam", Code1),
+ ok.
+
%% Utilities.
make_sub_binary(Bin) when is_binary(Bin) ->
diff --git a/erts/emulator/test/code_SUITE_data/fun_confusion.erl b/erts/emulator/test/code_SUITE_data/fun_confusion.erl
new file mode 100644
index 0000000000..16000861df
--- /dev/null
+++ b/erts/emulator/test/code_SUITE_data/fun_confusion.erl
@@ -0,0 +1,31 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 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
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(fun_confusion).
+
+-export([f/0]).
+
+f() ->
+ fun() -> version() end.
+
+version() ->
+ %% Changing the value returned here should change
+ %% the identity of the fun in f/0.
+ ?version.
+
diff --git a/lib/compiler/src/beam_asm.erl b/lib/compiler/src/beam_asm.erl
index 6e63c4d0f2..9b46abe697 100644
--- a/lib/compiler/src/beam_asm.erl
+++ b/lib/compiler/src/beam_asm.erl
@@ -146,8 +146,10 @@ build_file(Code, Attr, Dict, NumLabels, NumFuncs, Abst, SourceFile, Opts) ->
Essentials0 = [AtomChunk,CodeChunk,StringChunk,ImportChunk,
ExpChunk,LambdaChunk,LiteralChunk],
- Essentials = [iolist_to_binary(C) || C <- Essentials0],
- {Attributes,Compile} = build_attributes(Opts, SourceFile, Attr, Essentials),
+ Essentials1 = [iolist_to_binary(C) || C <- Essentials0],
+ MD5 = module_md5(Essentials1),
+ Essentials = finalize_fun_table(Essentials1, MD5),
+ {Attributes,Compile} = build_attributes(Opts, SourceFile, Attr, MD5),
AttrChunk = chunk(<<"Attr">>, Attributes),
CompileChunk = chunk(<<"CInf">>, Compile),
@@ -166,6 +168,24 @@ build_file(Code, Attr, Dict, NumLabels, NumFuncs, Abst, SourceFile, Opts) ->
end,
build_form(<<"BEAM">>, Chunks).
+%% finalize_fun_table(Essentials, MD5) -> FinalizedEssentials
+%% Update the 'old_uniq' field in the entry for each fun in the
+%% 'FunT' chunk. We'll use part of the MD5 for the module as a
+%% unique value.
+
+finalize_fun_table(Essentials, MD5) ->
+ [finalize_fun_table_1(E, MD5) || E <- Essentials].
+
+finalize_fun_table_1(<<"FunT",Keep:8/binary,Table0/binary>>, MD5) ->
+ <<Uniq:27,_:101/bits>> = MD5,
+ Table = finalize_fun_table_2(Table0, Uniq, <<>>),
+ <<"FunT",Keep/binary,Table/binary>>;
+finalize_fun_table_1(Chunk, _) -> Chunk.
+
+finalize_fun_table_2(<<Keep:20/binary,0:32,T/binary>>, Uniq, Acc) ->
+ finalize_fun_table_2(T, Uniq, <<Acc/binary,Keep/binary,Uniq:32>>);
+finalize_fun_table_2(<<>>, _, Acc) -> Acc.
+
%% Build an IFF form.
build_form(Id, Chunks0) when byte_size(Id) =:= 4, is_list(Chunks0) ->
@@ -202,7 +222,7 @@ flatten_exports(Exps) ->
flatten_imports(Imps) ->
list_to_binary(map(fun({M,F,A}) -> <<M:32,F:32,A:32>> end, Imps)).
-build_attributes(Opts, SourceFile, Attr, Essentials) ->
+build_attributes(Opts, SourceFile, Attr, MD5) ->
Misc = case member(slim, Opts) of
false ->
{{Y,Mo,D},{H,Mi,S}} = erlang:universaltime(),
@@ -210,7 +230,7 @@ build_attributes(Opts, SourceFile, Attr, Essentials) ->
true -> []
end,
Compile = [{options,Opts},{version,?COMPILER_VSN}|Misc],
- {term_to_binary(calc_vsn(Attr, Essentials)),term_to_binary(Compile)}.
+ {term_to_binary(set_vsn_attribute(Attr, MD5)),term_to_binary(Compile)}.
build_line_table(Dict) ->
{NumLineInstrs,NumFnames0,Fnames0,NumLines,Lines0} =
@@ -243,32 +263,30 @@ encode_line_items([], _) -> [].
%% We'll not change an existing 'vsn' attribute.
%%
-calc_vsn(Attr, Essentials0) ->
+set_vsn_attribute(Attr, MD5) ->
case keymember(vsn, 1, Attr) of
true -> Attr;
false ->
- Essentials = filter_essentials(Essentials0),
- <<Number:128>> = erlang:md5(Essentials),
+ <<Number:128>> = MD5,
[{vsn,[Number]}|Attr]
end.
+module_md5(Essentials0) ->
+ Essentials = filter_essentials(Essentials0),
+ erlang:md5(Essentials).
+
%% filter_essentials([Chunk]) -> [Chunk']
%% Filter essentials so that we obtain the same MD5 as code:module_md5/1 and
-%% beam_lib:md5/1 would calculate for this module.
+%% beam_lib:md5/1 would calculate for this module. Note that at this
+%% point, the 'old_uniq' entry for each fun in the 'FunT' chunk is zeroed,
+%% so there is no need to go through the 'FunT' chunk.
-filter_essentials([<<"FunT",_Sz:4/binary,Entries:4/binary,Table0/binary>>|T]) ->
- Table = filter_funtab(Table0, <<0:32>>),
- [Entries,Table|filter_essentials(T)];
filter_essentials([<<_Tag:4/binary,Sz:32,Data:Sz/binary,_Padding/binary>>|T]) ->
[Data|filter_essentials(T)];
filter_essentials([<<>>|T]) ->
filter_essentials(T);
filter_essentials([]) -> [].
-filter_funtab(<<Important:20/binary,_OldUniq:4/binary,T/binary>>, Zero) ->
- [Important,Zero|filter_funtab(T, Zero)];
-filter_funtab(<<>>, _) -> [].
-
bif_type(fnegate, 1) -> {op,fnegate};
bif_type(fadd, 2) -> {op,fadd};
bif_type(fsub, 2) -> {op,fsub};
@@ -310,8 +328,8 @@ make_op({test,Cond,Fail,Ops}, Dict) when is_list(Ops) ->
encode_op(Cond, [Fail|Ops], Dict);
make_op({test,Cond,Fail,Live,[Op|Ops],Dst}, Dict) when is_list(Ops) ->
encode_op(Cond, [Fail,Op,Live|Ops++[Dst]], Dict);
-make_op({make_fun2,{f,Lbl},Index,OldUniq,NumFree}, Dict0) ->
- {Fun,Dict} = beam_dict:lambda(Lbl, Index, OldUniq, NumFree, Dict0),
+make_op({make_fun2,{f,Lbl},Index,_OldUniq,NumFree}, Dict0) ->
+ {Fun,Dict} = beam_dict:lambda(Lbl, Index, NumFree, Dict0),
make_op({make_fun2,Fun}, Dict);
make_op({kill,Y}, Dict) ->
make_op({init,Y}, Dict);
diff --git a/lib/compiler/src/beam_dict.erl b/lib/compiler/src/beam_dict.erl
index ee76623976..f82a8f2e3e 100644
--- a/lib/compiler/src/beam_dict.erl
+++ b/lib/compiler/src/beam_dict.erl
@@ -22,7 +22,7 @@
-export([new/0,opcode/2,highest_opcode/1,
atom/2,local/4,export/4,import/4,
- string/2,lambda/5,literal/2,line/2,fname/2,
+ string/2,lambda/4,literal/2,line/2,fname/2,
atom_table/1,local_table/1,export_table/1,import_table/1,
string_table/1,lambda_table/1,literal_table/1,
line_table/1]).
@@ -133,13 +133,16 @@ string(Str, Dict) when is_list(Str) ->
{NextOffset-Offset,Dict}
end.
-%% Returns the index for a funentry (adding it to the table if necessary).
-%% lambda(Lbl, Index, Uniq, NumFree, Dict) -> {Index,Dict'}
--spec lambda(label(), non_neg_integer(), integer(), non_neg_integer(), bdict()) ->
+%% Returns the index for a fun entry.
+%% lambda(Lbl, Index, NumFree, Dict) -> {Index,Dict'}
+-spec lambda(label(), non_neg_integer(), non_neg_integer(), bdict()) ->
{non_neg_integer(), bdict()}.
-lambda(Lbl, Index, OldUniq, NumFree, #asm{lambdas=Lambdas0}=Dict) ->
+lambda(Lbl, Index, NumFree, #asm{lambdas=Lambdas0}=Dict) ->
OldIndex = length(Lambdas0),
+ %% Initialize OldUniq to 0. It will be set to an unique value
+ %% based on the MD5 checksum of the BEAM code for the module.
+ OldUniq = 0,
Lambdas = [{Lbl,{OldIndex,Lbl,Index,NumFree,OldUniq}}|Lambdas0],
{OldIndex,Dict#asm{lambdas=Lambdas}}.
diff --git a/lib/tools/test/cover_SUITE.erl b/lib/tools/test/cover_SUITE.erl
index fe7f92de78..881a3c2997 100644
--- a/lib/tools/test/cover_SUITE.erl
+++ b/lib/tools/test/cover_SUITE.erl
@@ -583,21 +583,14 @@ otp_6115_1(Config) ->
%% called -- running cover compiled code when there is no cover
%% server and thus no ets tables to bump counters in, makes no
%% sense.
- ?line Pid1 = f1:start_fail(),
-
- %% If f1 is cover compiled, a process P is started with a
- %% reference to the fun created in start_ok/0, and
- %% cover:stop() is called, then P should survive.
- %% This is because (the fun held by) P always references the current
- %% version of the module, and is thus not affected by the cover
- %% compiled version being unloaded.
- ?line Pid2 = f1:start_ok(),
+ Pid1 = f1:start_a(),
+ Pid2 = f1:start_b(),
%% Now stop cover
?line cover:stop(),
- %% Ensure that f1 is loaded (and not cover compiled), that Pid1
- %% is dead and Pid2 is alive, but with no reference to old code
+ %% Ensure that f1 is loaded (and not cover compiled), and that
+ %% both Pid1 and Pid2 are dead.
case code:which(f1) of
Beam when is_list(Beam) ->
ok;
@@ -608,19 +601,15 @@ otp_6115_1(Config) ->
undefined ->
ok;
_PI1 ->
- RefToOldP = erlang:check_process_code(Pid1, f1),
- ?line ?t:fail({"Pid1 still alive", RefToOldP})
+ RefToOldP1 = erlang:check_process_code(Pid1, f1),
+ ?t:fail({"Pid1 still alive", RefToOldP1})
end,
case process_info(Pid2) of
- PI2 when is_list(PI2) ->
- case erlang:check_process_code(Pid2, f2) of
- false ->
- ok;
- true ->
- ?line ?t:fail("Pid2 has ref to old code")
- end;
undefined ->
- ?line ?t:fail("Pid2 has died")
+ ok;
+ _PI2 ->
+ RefToOldP2 = erlang:check_process_code(Pid1, f2),
+ ?t:fail({"Pid2 still alive", RefToOldP2})
end,
?line file:set_cwd(CWD),
diff --git a/lib/tools/test/cover_SUITE_data/otp_6115/f1.erl b/lib/tools/test/cover_SUITE_data/otp_6115/f1.erl
index b659e5d818..5399b33f19 100644
--- a/lib/tools/test/cover_SUITE_data/otp_6115/f1.erl
+++ b/lib/tools/test/cover_SUITE_data/otp_6115/f1.erl
@@ -1,12 +1,13 @@
-module(f1).
--export([start_fail/0, start_ok/0]).
+-export([start_a/0, start_b/0]).
-start_fail() ->
+start_a() ->
f2:start(fun() ->
- io:format("this does not work\n",[])
+ ok
end).
-start_ok() ->
+start_b() ->
f2:start(fun fun1/0).
+
fun1() ->
- io:format("this works\n",[]).
+ ok.
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-03 01:53:35 +0000