Bug #9377: Seg fault on call of missing super from self.extended in a Module

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: 2.1.0
• Backport: 1.9.3: DONTNEED, 2.0.0: DONE, 2.1: DONE

[jemc (Joe McIlvain)]

Seg fault on call of missing super from self.extended in a Module
on 2.1.0-p0 and on 2.1.0-dev
x86_64 linux

Code to reproduce:

module A
  def foo; super end

  def self.extended(obj)
    instance_method(:foo).bind(obj).call
  end
end

Object.new.extend A

(stack trace is attached)

Note that calling from after extend is okay: (but raises missing super error)

module A
  def foo; super end
end

Object.new.extend(A).foo #=> in `foo': super: no superclass method `foo' for #<Object:0x007fabf43d2730> (NoMethodError)

Also note that calling from within the extend as before, but having the method defined is also okay (and raises no error)

module ABase
  def foo; end
end

module A
  include ABase
  def foo; super end

  def self.extended(obj)
    instance_method(:foo).bind(obj).call
  end
end

Object.new.extend A

[nobu (Nobuyoshi Nakada)]

• Description updated (diff)

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r44527.
Joe, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

vm_insnhelper.c: revive r44455 for bound module method

• vm_insnhelper.c (vm_search_super_method): when super called in a
  bound UnboundMethod generated from a module, no superclass is
  found since the current defined class is the module, then call
  method_missing in that case. [ruby-core:59619] [Bug #9377]

[nobu (Nobuyoshi Nakada)]

• Backport changed from 1.9.3: UNKNOWN, 2.0.0: UNKNOWN, 2.1: UNKNOWN to 1.9.3: DONTNEED, 2.0.0: REQUIRED, 2.1: REQUIRED

Since 2.0, vm_search_superclass() doesn't traverse the receiver's ancestors.
It works just because an invalid klass is not dereferenced accidentally.

[nagachika (Tomoyuki Chikanaga)]

• Backport changed from 1.9.3: DONTNEED, 2.0.0: REQUIRED, 2.1: REQUIRED to 1.9.3: DONTNEED, 2.0.0: DONE, 2.1: REQUIRED

r44527 was backported to ruby_2_0_0 at r45051.

[nobu (Nobuyoshi Nakada)]

• Description updated (diff)

[naruse (Yui NARUSE)]

• Backport changed from 1.9.3: DONTNEED, 2.0.0: DONE, 2.1: REQUIRED to 1.9.3: DONTNEED, 2.0.0: DONE, 2.1: DONE

ruby_2_1 r44843 merged revision(s) 44527,44552,44553.