Re: Assign Reference to another Referance

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Sat, 26 Sep 2009 04:05:50 -0700 (PDT)

Message-ID:

<49418d5b-f114-4b8e-94e4-a45469b37ef5@m20g2000vbp.googlegroups.com>

On Sep 25, 10:40 pm, cpisz <cp...@austin.rr.com> wrote:

I'll give you a compilable example as
soon as I get VS fixed later today.

Good! Please do so!

class Singleton
{
public:
   static Singleton & Instance()
   {
      if( !m_instance )
      {
         m_instance = new Singleton();
      }
      return *m_instance;
   }

   static void DoStuff()
   {
      int x = 1 + 1;
   }

private:
   static Singleton * m_instance;
};

Singleton * Singleton::m_instance = 0;

class Foo
{
public:

   Foo(){}
   ~Foo()
   {
      Singleton::Instance().DoStuff();
   }
};

int main()
{
   static Foo foo;
   return 0; // Undefined behavior after this line, when program
cleanup occurs!

Sorry, but this is just false. There's absolutely no undefined
behavior in the above code. It's fully conformant, legal and
well defined, and works on every C++ implementation I've tried.

}

static de-initialization fiasco.

Given that there's only one object in the code (the foo in main)
which is de-initialized, there can be no problem with order.

--
James Kanze