From 890bc8dddd62b5e14fd9bd38ea3317e47cc0b716 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Wed, 17 May 2017 12:38:09 +0200 Subject: escript: Pick up stacktrace a soon as possible It happens to work today, but it is potentially unsafe to call io:format/2 before calling erlang:get_stacktrace/0. Make the code safe by calling erlang:get_stacktrace/0 directly after catching the exception. --- lib/stdlib/src/escript.erl | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/stdlib/src/escript.erl b/lib/stdlib/src/escript.erl index 6e8f780f7c..f2629a47c2 100644 --- a/lib/stdlib/src/escript.erl +++ b/lib/stdlib/src/escript.erl @@ -284,8 +284,9 @@ start(EscriptOptions) -> io:format("escript: ~s\n", [Str]), my_halt(127); _:Reason -> + Stk = erlang:get_stacktrace(), io:format("escript: Internal error: ~p\n", [Reason]), - io:format("~p\n", [erlang:get_stacktrace()]), + io:format("~p\n", [Stk]), my_halt(127) end. -- cgit v1.2.3 From 652486205f6bfd32721f618c1191422182e77553 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Wed, 17 May 2017 13:06:36 +0200 Subject: proc_lib: Don't call erlang:get_stacktrace/0 twice proc_lib calls erlang:get_stacktrace/0 twice, which is unnecessary, and potentially unsafe since there are calls to many functions in between. Any of the calls could potentially cause and catch an exception, invalidating the stacktrace. Only call erlang:get_stacktrace/0 once, and pass the result to the second place where it is needed. --- lib/stdlib/src/proc_lib.erl | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/lib/stdlib/src/proc_lib.erl b/lib/stdlib/src/proc_lib.erl index 363705b0f4..2219467a8d 100644 --- a/lib/stdlib/src/proc_lib.erl +++ b/lib/stdlib/src/proc_lib.erl @@ -264,12 +264,12 @@ exit_p(Class, Reason, Stacktrace) -> case get('$initial_call') of {M,F,A} when is_atom(M), is_atom(F), is_integer(A) -> MFA = {M,F,make_dummy_args(A, [])}, - crash_report(Class, Reason, MFA), + crash_report(Class, Reason, MFA, Stacktrace), erlang:raise(exit, exit_reason(Class, Reason, Stacktrace), Stacktrace); _ -> %% The process dictionary has been cleared or %% possibly modified. - crash_report(Class, Reason, []), + crash_report(Class, Reason, [], Stacktrace), erlang:raise(exit, exit_reason(Class, Reason, Stacktrace), Stacktrace) end. @@ -499,24 +499,25 @@ trans_init(M, F, A) when is_atom(M), is_atom(F) -> %% Generate a crash report. %% ----------------------------------------------------- -crash_report(exit, normal, _) -> ok; -crash_report(exit, shutdown, _) -> ok; -crash_report(exit, {shutdown,_}, _) -> ok; -crash_report(Class, Reason, StartF) -> - OwnReport = my_info(Class, Reason, StartF), +crash_report(exit, normal, _, _) -> ok; +crash_report(exit, shutdown, _, _) -> ok; +crash_report(exit, {shutdown,_}, _, _) -> ok; +crash_report(Class, Reason, StartF, Stacktrace) -> + OwnReport = my_info(Class, Reason, StartF, Stacktrace), LinkReport = linked_info(self()), Rep = [OwnReport,LinkReport], error_logger:error_report(crash_report, Rep). -my_info(Class, Reason, []) -> - my_info_1(Class, Reason); -my_info(Class, Reason, StartF) -> - [{initial_call, StartF}|my_info_1(Class, Reason)]. +my_info(Class, Reason, [], Stacktrace) -> + my_info_1(Class, Reason, Stacktrace); +my_info(Class, Reason, StartF, Stacktrace) -> + [{initial_call, StartF}| + my_info_1(Class, Reason, Stacktrace)]. -my_info_1(Class, Reason) -> +my_info_1(Class, Reason, Stacktrace) -> [{pid, self()}, get_process_info(self(), registered_name), - {error_info, {Class,Reason,erlang:get_stacktrace()}}, + {error_info, {Class,Reason,Stacktrace}}, get_ancestors(self()), get_process_info(self(), messages), get_process_info(self(), links), -- cgit v1.2.3