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-rw-r--r--lib/compiler/src/sys_core_fold.erl25
-rw-r--r--lib/compiler/test/core_fold_SUITE.erl36
-rw-r--r--lib/ssh/src/ssh_file.erl26
3 files changed, 68 insertions, 19 deletions
diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl
index 9ce6bb48bf..e302e2324d 100644
--- a/lib/compiler/src/sys_core_fold.erl
+++ b/lib/compiler/src/sys_core_fold.erl
@@ -1945,9 +1945,30 @@ eval_case(#c_case{arg=E,clauses=[#c_clause{pats=Ps0,body=B}]}, Sub) ->
true -> cerl:values_es(E);
false -> [E]
end,
- {true,Bs} = cerl_clauses:match_list(Ps0, Es),
+ %% Consider:
+ %%
+ %% case SomeSideEffect() of
+ %% X=Y -> ...
+ %% end
+ %%
+ %% We must not rewrite it to:
+ %%
+ %% let <X,Y> = <SomeSideEffect(),SomeSideEffect()> in ...
+ %%
+ %% because SomeSideEffect() would be called evaluated twice.
+ %%
+ %% Instead we must evaluate the case expression in an outer let
+ %% like this:
+ %%
+ %% let NewVar = SomeSideEffect() in
+ %% let <X,Y> = <NewVar,NewVar> in ...
+ %%
+ Vs = make_vars([], length(Es)),
+ {true,Bs} = cerl_clauses:match_list(Ps0, Vs),
{Ps,As} = unzip(Bs),
- expr(#c_let{vars=Ps,arg=core_lib:make_values(As),body=B}, sub_new(Sub));
+ InnerLet = cerl:c_let(Ps, core_lib:make_values(As), B),
+ Let = cerl:c_let(Vs, E, InnerLet),
+ expr(Let, sub_new(Sub));
eval_case(Case, _) -> Case.
%% case_opt(CaseArg, [Clause]) -> {CaseArg,[Clause]}.
diff --git a/lib/compiler/test/core_fold_SUITE.erl b/lib/compiler/test/core_fold_SUITE.erl
index 69f61a046f..8151dc1b16 100644
--- a/lib/compiler/test/core_fold_SUITE.erl
+++ b/lib/compiler/test/core_fold_SUITE.erl
@@ -22,7 +22,8 @@
init_per_group/2,end_per_group/2,
t_element/1,setelement/1,t_length/1,append/1,t_apply/1,bifs/1,
eq/1,nested_call_in_case/1,guard_try_catch/1,coverage/1,
- unused_multiple_values_error/1,unused_multiple_values/1]).
+ unused_multiple_values_error/1,unused_multiple_values/1,
+ multiple_aliases/1]).
-export([foo/0,foo/1,foo/2,foo/3]).
@@ -38,7 +39,8 @@ groups() ->
[{p,test_lib:parallel(),
[t_element,setelement,t_length,append,t_apply,bifs,
eq,nested_call_in_case,guard_try_catch,coverage,
- unused_multiple_values_error,unused_multiple_values]}].
+ unused_multiple_values_error,unused_multiple_values,
+ multiple_aliases]}].
init_per_suite(Config) ->
@@ -299,8 +301,6 @@ cover_is_safe_bool_expr(X) ->
bsm_an_inlined(<<_:8>>, _) -> ok;
bsm_an_inlined(_, _) -> error.
-id(I) -> I.
-
unused_multiple_values_error(Config) when is_list(Config) ->
PrivDir = ?config(priv_dir, Config),
Dir = filename:dirname(code:which(?MODULE)),
@@ -338,3 +338,31 @@ do_something(I) ->
put(unused_multiple_values,
[I|get(unused_multiple_values)]),
I.
+
+
+%% Make sure that multiple aliases does not cause
+%% the case expression to be evaluated twice.
+multiple_aliases(Config) when is_list(Config) ->
+ do_ma(fun() ->
+ X = Y = run_once(),
+ {X,Y}
+ end, {ok,ok}),
+ do_ma(fun() ->
+ case {true,run_once()} of
+ {true=A=B,ok=X=Y} ->
+ {A,B,X,Y}
+ end
+ end, {true,true,ok,ok}),
+ ok.
+
+do_ma(Fun, Expected) when is_function(Fun, 0) ->
+ Expected = Fun(),
+ ran_once = erase(run_once),
+ ok.
+
+run_once() ->
+ undefined = put(run_once, ran_once),
+ ok.
+
+
+id(I) -> I.
diff --git a/lib/ssh/src/ssh_file.erl b/lib/ssh/src/ssh_file.erl
index 21cdedc156..5692138a8a 100644
--- a/lib/ssh/src/ssh_file.erl
+++ b/lib/ssh/src/ssh_file.erl
@@ -65,7 +65,7 @@ is_auth_key(Key, User,Opts) ->
%% Used by client
is_host_key(Key, PeerName, Algorithm, Opts) ->
- case lookup_host_key(PeerName, Algorithm, Opts) of
+ case lookup_host_key(Key, PeerName, Algorithm, Opts) of
{ok, Key} ->
true;
_ ->
@@ -121,9 +121,9 @@ decode_ssh_file(Pem, Password) ->
%% return {ok, Key(s)} or {error, not_found}
%%
-lookup_host_key(Host, Alg, Opts) ->
+lookup_host_key(KeyToMatch, Host, Alg, Opts) ->
Host1 = replace_localhost(Host),
- do_lookup_host_key(Host1, Alg, Opts).
+ do_lookup_host_key(KeyToMatch, Host1, Alg, Opts).
add_host_key(Host, Key, Opts) ->
@@ -204,10 +204,10 @@ replace_localhost("localhost") ->
replace_localhost(Host) ->
Host.
-do_lookup_host_key(Host, Alg, Opts) ->
+do_lookup_host_key(KeyToMatch, Host, Alg, Opts) ->
case file:open(file_name(user, "known_hosts", Opts), [read, binary]) of
{ok, Fd} ->
- Res = lookup_host_key_fd(Fd, Host, Alg),
+ Res = lookup_host_key_fd(Fd, KeyToMatch, Host, Alg),
file:close(Fd),
{ok, Res};
{error, enoent} -> {error, not_found};
@@ -228,16 +228,16 @@ identity_pass_phrase('ssh-rsa') ->
identity_pass_phrase("ssh-rsa") ->
rsa_pass_phrase.
-lookup_host_key_fd(Fd, Host, KeyType) ->
+lookup_host_key_fd(Fd, KeyToMatch, Host, KeyType) ->
case io:get_line(Fd, '') of
eof ->
{error, not_found};
Line ->
case ssh_decode_line(Line, known_hosts) of
[{Key, Attributes}] ->
- handle_host(Fd, Host, proplists:get_value(hostnames, Attributes), Key, KeyType);
+ handle_host(Fd, KeyToMatch, Host, proplists:get_value(hostnames, Attributes), Key, KeyType);
[] ->
- lookup_host_key_fd(Fd, Host, KeyType)
+ lookup_host_key_fd(Fd, KeyToMatch, Host, KeyType)
end
end.
@@ -248,13 +248,13 @@ ssh_decode_line(Line, Type) ->
[]
end.
-handle_host(Fd, Host, HostList, Key, KeyType) ->
+handle_host(Fd, KeyToMatch, Host, HostList, Key, KeyType) ->
Host1 = host_name(Host),
- case lists:member(Host1, HostList) and key_match(Key, KeyType) of
- true ->
+ case lists:member(Host1, HostList) andalso key_match(Key, KeyType) of
+ true when KeyToMatch == Key ->
Key;
- false ->
- lookup_host_key_fd(Fd, Host, KeyType)
+ _ ->
+ lookup_host_key_fd(Fd, KeyToMatch, Host, KeyType)
end.
host_name(Atom) when is_atom(Atom) ->
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-22 15:44:14 +0000