Re: Is it an undefined behavior in C++ Standard?

From: aka (akademecia_at_hotmail.com)
Date: 03/13/05

  • Next message: Jon Slaughter: "Re: Classses of each other" 
    Date: Sun, 13 Mar 2005 16:03:11 +0800

    I'm learning Visual C++ 2005. I want to know how it implement ISO C++
    standard, such as undefined behavior.

    "Peter Koch Larsen" <pklspam@mailme.dk> дÈëÏûÏ¢
    news:zRgYd.104094$Vf.3990245@news000.worldonline.dk...
    >
    > "aka" <akademecia@hotmail.com> skrev i en meddelelse
    > news:d0s4l9$kdm$1@news.yaako.com...
    > > // classA.cpp : Defines the entry point for the console application.
    > > //
    > >
    > > #include "stdafx.h"
    > >
    > > #include <iostream>
    > >
    > > using namespace std;
    > >
    > > static unsigned int count = 0;
    > >
    > > class A
    > > {
    > > public:
    > > A() {
    > > p = this;
    > > }
    > >
    > > ~A() {
    > > if (p) {
    > > cout << count++ << endl;
    > > delete p;
    > > p = 0;
    > > }
    > > }
    > >
    > > private:
    > > A *p;
    > > };
    > >
    > > int _tmain(int argc, _TCHAR* argv[])
    > > {
    > > A a;
    > >
    > > return 0;
    > > }
    > >
    > > /* compiler: MSC++ compiler in visual c++ 2005 express edition beta
    > > command: cl /nologo /EHsc classA.cpp
    > > */
    > >
    > > /* result:
    > > 0
    > > 1
    > > 2
    > > ...
    > > 23485
    > > press any key to continue
    > > */
    > >
    > > /*
    > > question: Is it an undefined behavior in C++ Standard?
    > What is? What you do is calling the destructor of an object more than once
    > and that causes undefined behaviour.
    > >
    > > details: p is a point of class A, when destructor call 'delete p',it
    will
    > > cause destructor again.
    > > Is there any limit calling destructor recursively?
    >
    > No. You can do as long as you please. Almost! Your program
    > Not in your program - it has endless recursion.
    >
    > Also I fail to sees what youre attempting to do.
    >
    >
    > /Peter
    >
    > > */ÿÿÿ
    > >
    > >
    >
    >

  • Next message: Jon Slaughter: "Re: Classses of each other"

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