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Re: C++ standard library and exceptions

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On Monday, December 19, 2011 6:38:03 PM UTC+8, Sektor van Skijlen wrote:
> On Dec 12, 6:28 pm, Kaz Kylheku <k....@kylheku.com> wrote:
> > > Well-defined programs cannot have any segfault... Any program having a
> > > segfault is in inconsistent state. Important data may have been
> > > damaged, and there is no guarantee of any sort of recovery.
> >
> > Sorry, that's a ridiculous assertion. Catching segfaults is a useful
> > software technique that can be used to do cool things.  A software emulator for
> > a CPU can catch a segfault to detect that writes are taking place to simulated
> > I/O space.  Garbage collectors can use segfaults. Some Lisp implementations
> > catch SIGSEGV as part of their garbage collector implementation. For instance
> > CLISP has a "libsigsegv" library for handling access violations and fixing them
> > up:
> >
> > http://libsigsegv.sourceforge.net/
> 
> That's an implementation detail, strongly cooperating with system
> level. It has
> completely nothing to do with SEGV occuring in C++ programs.
> 
> > > For the sake of security and data integrity, a good system detecting
> > > such an error, should kill/abort/terminate the program immediately.
> >
> > That is a silly view. Detecting the error already provides security and
> > integrity.
> 
> SEGV is not "detecting the error". SEGV is detecting the situation
> that shouldn't
> have occurred - it means that, of course, reporting SEGV means error,
> but this
> can quickly lead us to a statement that "not reporting SEGV means no
> error in
> data integrity", which is not true anyway - SEGV might have been only
> one of
> possible realizations of "undefined behavior". Others are e.g. writing
> to a
> memory not expected to be written.
> 
> What I mean is that SEGV doesn't just mean that "well, some error
> happened".

In a true virtual memory system of a robust OS, 
it is not allowed to write directly  to some wrong address outside those
allowed.

But this does not solve any indirect calling dead cycle formed 
by lousy  programs. 

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C++ standard library and exceptions ittium <ittium@gmail.com> - 2011-12-08 12:17 +0530
  Re: C++ standard library and exceptions ittium <ittium@gmail.com> - 2011-12-08 12:22 +0530
  Re: C++ standard library and exceptions Goran <goran.pusic@gmail.com> - 2011-12-08 01:02 -0800
    Re: C++ standard library and exceptions ittium <ittium@gmail.com> - 2011-12-08 16:35 +0530
      Re: C++ standard library and exceptions Goran <goran.pusic@gmail.com> - 2011-12-08 05:08 -0800
        Re: C++ standard library and exceptions ittium <ittium@gmail.com> - 2011-12-10 13:46 +0530
          Re: C++ standard library and exceptions "io_x" <a@b.c.invalid> - 2011-12-11 05:43 +0100
            Re: C++ standard library and exceptions "io_x" <a@b.c.invalid> - 2011-12-12 03:21 +0100
            Re: C++ standard library and exceptions André Gillibert <MetaEntropy.removeThis@gmail.com> - 2011-12-12 11:15 +0100
              Re: C++ standard library and exceptions Nobody <nobody@nowhere.com> - 2011-12-12 12:59 +0000
              Re: C++ standard library and exceptions Kaz Kylheku <kaz@kylheku.com> - 2011-12-12 17:28 +0000
                Re: C++ standard library and exceptions Paavo Helde <myfirstname@osa.pri.ee> - 2011-12-12 12:42 -0600
                Re: C++ standard library and exceptions Joshua Maurice <joshuamaurice@gmail.com> - 2011-12-12 14:18 -0800
                Re: C++ standard library and exceptions Sektor van Skijlen <ethouris@gmail.com> - 2011-12-19 02:38 -0800
                Re: C++ standard library and exceptions 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-19 03:52 -0800
              Re: C++ standard library and exceptions "io_x" <a@b.c.invalid> - 2011-12-13 09:16 +0100
              Re: C++ standard library and exceptions "io_x" <a@b.c.invalid> - 2011-12-13 09:17 +0100
                Re: C++ standard library and exceptions "Wolfgang.Draxinger" <Wolfgang.Draxinger@physik.uni-muenchen.de> - 2011-12-15 12:14 +0100
                Re: C++ standard library and exceptions Joshua Maurice <joshuamaurice@gmail.com> - 2011-12-15 15:50 -0800
                Re: C++ standard library and exceptions hanukas <jukka@liimatta.org> - 2011-12-17 21:57 -0800
                Re: C++ standard library and exceptions "io_x" <a@b.c.invalid> - 2011-12-19 04:02 +0100
                Re: C++ standard library and exceptions Joshua Maurice <joshuamaurice@gmail.com> - 2011-12-19 01:32 -0800
                Re: C++ standard library and exceptions Tobias Müller <troplin@bluewin.ch> - 2011-12-19 07:14 +0000
                Re: C++ standard library and exceptions Joshua Maurice <joshuamaurice@gmail.com> - 2011-12-19 01:29 -0800

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