[ruby-core:55670] Re: [ruby-trunk - Bug #8538] c method not pushed into the callstack when called, but popped when returned

It seems like #initialize is never pushed to the stack:

  class Foo
    def initialize
      puts caller
    end
  end

  Foo.new

Result:

f.rb:8:in `new'
f.rb:8:in `<main>'



// Magnus Holm


On Thu, Jun 27, 2013 at 10:23 AM, deivid (David Rodr=C3=ADguez) <
[e-mail]> wrote:

>
> Issue #8538 has been updated by deivid (David Rodr=C3=ADguez).
>
>
> "no replies after 10 days" reminder. This is affecting
> https://github.com/deivid-rodriguez/byebug, I can easily make it crash by
> doing:
>
>     davidr@pantani:~/Proyectos/byebug$ ruby -Ilib -rbyebug -e 'byebug;
> fail "Bang!"'
>     -e @ 1
>     (byebug) catch Exception
>     Catch exception Exception.
>     (byebug) c
>     Catchpoint at -e:1: `Bang!' (RuntimeError)
>             from /home/davidr/Proyectos/byebug/lib/byebug/context.rb:44:i=
n
> `at_catchpoint'
>             from -e:1:in `<main>'
>     -e @ 1
>     (byebug) bt
>     --> #0  <main> at -e:1
>     INTERNAL ERROR!!! That frame doesn't exist!
>
> /home/davidr/Proyectos/byebug/lib/byebug/commands/frame.rb:90:in
> `frame_file'
>
> /home/davidr/Proyectos/byebug/lib/byebug/commands/frame.rb:90:in
> `print_frame'
>
> /home/davidr/Proyectos/byebug/lib/byebug/commands/frame.rb:85:in `block i=
n
> print_backtrace'
>
> /home/davidr/Proyectos/byebug/lib/byebug/commands/frame.rb:84:in `each'
>
> /home/davidr/Proyectos/byebug/lib/byebug/commands/frame.rb:84:in
> `print_backtrace'
>
> /home/davidr/Proyectos/byebug/lib/byebug/commands/frame.rb:127:in `execut=
e'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:260:in
> `one_cmd'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:244:in
> `block (2 levels) in process_commands'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:243:in
> `each'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:243:in
> `block in process_commands'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:236:in
> `catch'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:236:in
> `process_commands'
>             /home/davidr/Proyectos/byebug/lib/byebug/processor.rb:158:in
> `at_line'
>             (eval):5:in `block in at_line'
>             (eval):3:in `synchronize'
>             (eval):3:in `at_line'
>             /home/davidr/Proyectos/byebug/lib/byebug/context.rb:52:in
> `at_line'
>             -e:1:in `<main>'-e:1:in `<main>': Bang! (RuntimeError)
>
> When the raise event comes, byebug thinks the stack size is 2 but there's
> only one element. I think this is caused by the inconsistent behaviour
> explained above.
>
> Thanks a lot guys!
> ----------------------------------------
> Bug #8538: c method not pushed into the callstack when called, but popped
> when returned
> https://bugs.ruby-lang.org/issues/8538#change-40173
>
> Author: deivid (David Rodr=C3=ADguez)
> Status: Open
> Priority: Normal
> Assignee:
> Category:
> Target version:
> ruby -v: ruby 2.0.0p195 (2013-05-14) [i686-linux]
> Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN
>
>
> See the following example:
>
>     trace =3D TracePoint.new do |tp|
>       puts "Event: #{tp.event}, Method: #{tp.method_id}\n"
>       puts "Stack: #{caller}\n\n"
>     end
>
>     trace.enable
>
>     fail "bang!"
>
> The output shows:
>
>     Event: c_return, Method: enable
>     Stack: ["trace.rb:6:in `<main>'"]
>
>     Event: line, Method:
>     Stack: ["trace.rb:8:in `<main>'"]
>
>     Event: c_call, Method: fail
>     Stack: ["trace.rb:8:in `<main>'"]
>
>     Event: c_call, Method: new
>     Stack: ["trace.rb:8:in `fail'", "trace.rb:8:in `<main>'"]
>
>     Event: c_call, Method: initialize
>     Stack: ["trace.rb:8:in `new'", "trace.rb:8:in `fail'", "trace.rb:8:in
> `<main>'"]
>
>     Event: c_return, Method: initialize
>     Stack: ["trace.rb:8:in `new'", "trace.rb:8:in `fail'", "trace.rb:8:in
> `<main>'"]
>
>     Event: c_return, Method: new
>     Stack: ["trace.rb:8:in `fail'", "trace.rb:8:in `<main>'"]
>
>     Event: c_call, Method: backtrace
>     Stack: ["trace.rb:8:in `<main>'"]
>
>     Event: c_return, Method: backtrace
>     Stack: ["trace.rb:8:in `<main>'"]
>
>     Event: raise, Method:
>     Stack: ["trace.rb:8:in `<main>'"]
>
>     Event: c_return, Method: fail
>     Stack: ["trace.rb:8:in `<main>'"]
>
>     trace.rb:8:in `<main>': bang! (RuntimeError)
>
> It looks like the method "initialize" is not pushed into the stack when
> called, but something (the previous method call) is popped when returning
> from it.
>
> Thanks a lot.
>
>
> --
> http://bugs.ruby-lang.org/
>
>