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From: "andy.m.jost at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/54770] sibling call optimization is not applied where it ought to be
Date: Tue, 20 Nov 2012 17:15:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54770

--- Comment #8 from Andy Jost <andy.m.jost at gmail dot com> 2012-11-20 17:14:18 UTC ---
The workaround I mentioned in comment #5 does seem to do the trick. 
Specifically, something like this works in all the cases I've tried:

  struct MainNode : Node
  {
    virtual void H()
    {
      helper()
      this->H();
    }
    __attribute__((noinline)) void helper()
    {
      NodePtr tmp(arg);
      this->~Node();
      new(this) MainNode(tmp);
    }
  };