Issue #8965 has been reported by shugo (Shugo Maeda).

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Bug #8965: SEGV when a refined method is undefined by undef
https://bugs.ruby-lang.org/issues/8965

Author: shugo (Shugo Maeda)
Status: Assigned
Priority: Normal
Assignee: shugo (Shugo Maeda)
Category: core
Target version: current: 2.1.0
ruby -v: ruby 2.1.0dev (2013-09-27 trunk 43073) [i686-linux]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


The following code causes SEGV:

  module Foo
    refine Object do
      def foo
        puts "foo"
      end
    end
  end
  
  using Foo
  
  class Object
    undef foo
  end
  
  foo

I guess undef is not aware of refinements.


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