Bug #12832
closed
Updated by shyouhei (Shyouhei Urabe) over 8 years ago
- Status changed from Open to Assigned
- Assignee set to ko1 (Koichi Sasada)
I can reproduce this. Seems like a infinite loop inside ofrb_callable_method_entry_without_refinements. I think this is a showstopper bug.
zsh % lldb ./miniruby target.rb
(lldb) target create "./miniruby"
Current executable set to './miniruby' (x86_64).
(lldb) settings set -- target.run-args "target.rb"
(lldb) run
Process 23728 launched: './miniruby' (x86_64)
Process 23728 stopped
* thread #1: tid = 0xea3fd, 0x00000001001f2535 miniruby`rb_callable_method_entry_without_refinements + 24 at vm_method.c:848, stop reason = signal SIGSTOP
frame #0: 0x00000001001f2535 miniruby`rb_callable_method_entry_without_refinements + 24 at vm_method.c:848
845 const rb_method_entry_t *me = method_entry_get(klass, id, defined_class_ptr);
846
847 if (me) {
-> 848 if (me->def->type == VM_METHOD_TYPE_REFINED) {
849 if (with_refinement) {
850 const rb_cref_t *cref = rb_vm_cref();
851 VALUE refinements = cref ? CREF_REFINEMENTS(cref) : Qnil;
(lldb) bt
* thread #1: tid = 0xea3fd, 0x00000001001f2535 miniruby`rb_callable_method_entry_without_refinements + 24 at vm_method.c:848, stop reason = signal SIGSTOP
* frame #0: 0x00000001001f2535 miniruby`rb_callable_method_entry_without_refinements + 24 at vm_method.c:848
frame #1: 0x00000001001f251d miniruby`rb_callable_method_entry_without_refinements(klass=<unavailable>, id=26065) + 13
frame #2: 0x000000010011d820 miniruby`mnew_internal(me=0x000000010185ec40, klass=4320521560, obj=4320521600, id=26065, mclass=4320688000, scope=0, error=1) + 96 at proc.c:1375
frame #3: 0x00000001001210f3 miniruby`rb_obj_method [inlined] mnew_from_me(scope=<unavailable>, mclass=<unavailable>, id=<unavailable>, obj=<unavailable>, klass=<unavailable>, me=<unavailable>) + 26 at proc.c:1403
frame #4: 0x00000001001210d9 miniruby`rb_obj_method + 24
frame #5: 0x00000001001210c1 miniruby`rb_obj_method + 84
frame #6: 0x000000010012106d miniruby`rb_obj_method(obj=4320521600, vid=<unavailable>) + 13
frame #7: 0x00000001001f0e56 miniruby`vm_call_cfunc + 184 at vm_insnhelper.c:1752
frame #8: 0x00000001001f0d9e miniruby`vm_call_cfunc(th=0x0000000100604310, reg_cfp=0x00000001007fffa0, calling=<unavailable>, ci=<unavailable>, cc=<unavailable>) + 46
frame #9: 0x00000001001ff3fe miniruby`vm_call_method_each_type(th=0x0000000100604310, cfp=0x00000001007fffa0, calling=0x00007fff5fbfd900, ci=<unavailable>, cc=<unavailable>) + 142 at vm_insnhelper.c:2138
frame #10: 0x00000001001ff95b miniruby`vm_call_method(th=0x0000000100604310, cfp=0x00000001007fffa0, calling=<unavailable>, ci=<unavailable>, cc=<unavailable>) + 235 at vm_insnhelper.c:2288
frame #11: 0x00000001001f8639 miniruby`vm_exec_core(th=0x0000000100604310, initial=<unavailable>) + 6217 at insns.def:1066
frame #12: 0x00000001001fdda3 miniruby`vm_exec(th=0x0000000100604310) + 131 at vm.c:1711
frame #13: 0x0000000100082bc0 miniruby`ruby_exec_internal(n=0x000000010185f9d8) + 176 at eval.c:244
frame #14: 0x000000010008686f miniruby`ruby_run_node [inlined] ruby_exec_node(n=<unavailable>) + 47 at eval.c:308
frame #15: 0x000000010008685b miniruby`ruby_run_node(n=<unavailable>) + 27
frame #16: 0x000000010021788e miniruby`main(argc=<unavailable>, argv=<unavailable>) + 78 at main.c:36
frame #17: 0x00007fff8dc4f5ad libdyld.dylib`start + 1
frame #18: 0x00007fff8dc4f5ad libdyld.dylib`start + 1
(lldb)
Updated by nagachika (Tomoyuki Chikanaga) over 8 years ago
- Backport changed from 2.1: UNKNOWN, 2.2: UNKNOWN, 2.3: UNKNOWN to 2.1: REQUIRED, 2.2: REQUIRED, 2.3: REQUIRED
Updated by floehopper (James Mead) over 8 years ago
In case it helps, it seems as if Ruby v2.3 is "more" broken than earlier versions. If I remove the Bar.method(:foo) lookup before the Baz module is prepended, the final lookup still hangs in Ruby v2.3, but not in v2.2. See below:
module Foo
private
def foo
"foo"
end
end
class Bar
extend Foo
class << self
public :foo
end
end
module Baz
end
class Bar
class << self
prepend Baz
end
end
Bar.method(:foo) # => hangs in Ruby v2.3.1, but not v2.2.5
Updated by chrisroos (Chris Roos) over 8 years ago
I'm not sure whether this is useful information but calling #instance_method on Bar's metaclass also causes Ruby to hang. Using James's most recent code snippet, the following code seems to cause the same problem as Bar.method(:foo).
metaclass = (class << Bar; self; end)
p metaclass.instance_method(:foo) # => hangs in Ruby v2.3.1, but not v2.2.5
Updated by nobu (Nobuyoshi Nakada) over 8 years ago
- Status changed from Assigned to Closed
Applied in changeset r56489.
proc.c: follow the original class
- proc.c (mnew_internal): follow the original class, not to loop
the prepended module. [ruby-core:77591] [Bug ]
Updated by floehopper (James Mead) over 8 years ago
@nobu (Nobuyoshi Nakada): Thank you for fixing this. Is it expected that a bug like this would cause the interpreter not to accept interrupt signals?
Updated by nobu (Nobuyoshi Nakada) over 8 years ago
It's not expected but a bug is always what causes unexpected behavior.
Updated by floehopper (James Mead) over 8 years ago
@nobu (Nobuyoshi Nakada): Is it possible there is a separate problem with the code such that interrupt signals are incorrectly being ignored...?
Updated by kernigh (George Koehler) over 8 years ago
Ruby defers signals. At safe moments, Ruby checks if a signal arrived, then handles it. If Ruby is stuck in an infinite loop (because of a bug like this one), then Ruby would never check if a signal arrived, so the signal would be ignored. After fixing the bug, signals should work again. Ruby's deferred signals seem like Perl's, see http://perldoc.perl.org/perlipc.html#Deferred-Signals-(Safe-Signals)
Updated by floehopper (James Mead) over 8 years ago
@George: Thanks for explaining. Makes sense.
Updated by nagachika (Tomoyuki Chikanaga) over 8 years ago
- Backport changed from 2.1: REQUIRED, 2.2: REQUIRED, 2.3: REQUIRED to 2.1: REQUIRED, 2.2: REQUIRED, 2.3: DONE
ruby_2_3 r56720 merged revision(s) 56489.
Updated by usa (Usaku NAKAMURA) over 8 years ago
- Backport changed from 2.1: REQUIRED, 2.2: REQUIRED, 2.3: DONE to 2.1: REQUIRED, 2.2: DONE, 2.3: DONE
ruby_2_2 r56731 merged revision(s) 56489.