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From: tiemann@ai.mit.edu (Micheal Tiemann)
Newsgroups: gnu.g++.bug
Subject: hard bug
Message-ID: <9001111953.AA13433@apple-gunkies.ai.mit.edu>
Date: 11 Jan 90 19:53:07 GMT
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Distribution: gnu
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Here's a C++ teaser.  What's wrong with the following code?

    extern "C" void printf (char *, ...);
    struct X
    {
      int x;

      X (int i) { x = i; }
      ~X () { printf ("destroying object %d\n", x); }
    };

    main ()
    {
      int i = foo ();

      if (i)
	for (X x(5); i < 10; i++)
	  {
	    printf ("loop count = %d\n", i);
	  }
      Greyhawk:
	;
    }

    int foo () { return 0; }

More precisely, when execution reaches Greyhawk,

	1.  Is `x' in scope?
	2.  If so, it is initialized?
	3.  Where and when is `x' destroyed?

If the scope of `x' were limited to the scope of the for loop, none of
these problems would be "interesting", and everything work work as one
might expect.

Michael