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Re: Remving an element from Queue

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On Wednesday, May 9, 2012 10:37:38 AM UTC+1, Bart wrote:
> <nick_keighley_nospam@hotmail.com> wrote in message
> news:17230148.361.1336546987566.JavaMail.geo-discussion-forums@vbcm9...
> > On Tuesday, May 8, 2012 2:03:48 PM UTC+1, Bart wrote:
> >> <nick_keighley_nospam@hotmail.com> wrote in message

> >> > Why didn't you use a debugger? That's how I found the bug.

<snip>

> >> No need for any debugger. And what exactly did it say anyway?
> >
> > well the program has Undefined Behaviour so the question isn't really
> > meaningful. Visual C++ gives:-
> >
> > "Unhandled exception at 0x00411cc9 in quick.exe: 0xC0000005: Access
> > violation reading location 0xcdcdcdcd."
> >
> > The debugger shows it crashed in printStruct() and p has an insane value.
> 
> As I said, when I tried it under one compiler, it just looped forever
> p;rinting the same sequence of 3 or 4 values, so p (ie. q->head) presumably
> had a sensible enough value.
> 
> Debuggers have their uses but are probably overkill for an obvious logic 
> error within the first dozen lines of execution!

and how would I know the crash was going to occur within a few dozen lines of startup?

> When a program goes wrong a few billion statements from the start, because
> of some unrelated code a billion or two statements back in a totally
> different part, then it might be time to wheel it out (and even then I'm not
> sure how they could help).

whatever. I judged running under a debugger was a quicker way to find the bug than ploughing through lots of source code. It so happened it pin-pointed the bug almost instantly.

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Thread

Remving an element from Queue arnuld <sunrise@invalid.address> - 2012-05-08 08:09 +0000
  Re: Remving an element from Queue Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-05-08 08:01 -0400
    Re: Remving an element from Queue arnuld <sunrise@invalid.address> - 2012-05-09 05:43 +0000
      Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-08 23:21 -0700
        Re: Remving an element from Queue arnuld <sunrise@invalid.address> - 2012-05-09 09:27 +0000
          Re: Remving an element from Queue James Kuyper <jameskuyper@verizon.net> - 2012-05-09 07:54 -0400
        Re: Remving an element from Queue arnuld <sunrise@invalid.address> - 2012-05-09 13:18 +0000
          Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-09 10:59 -0700
            Re: Remving an element from Queue arnuld <arnuld.mizong@gmail.com> - 2012-05-10 05:26 -0700
              Re: Remving an element from Queue nick_keighley_nospam@hotmail.com - 2012-05-11 00:11 -0700
              Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-14 15:53 -0700
                Re: Remving an element from Queue lawrence.jones@siemens.com - 2012-05-15 17:42 -0400
                Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-15 16:40 -0700
                Re: Remving an element from Queue James Kuyper <jameskuyper@verizon.net> - 2012-05-15 23:03 -0400
                Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-15 20:38 -0700
                Re: Remving an element from Queue Jens Gustedt <jens.gustedt@loria.fr> - 2012-05-16 08:09 +0200
                Re: Remving an element from Queue James Kuyper <jameskuyper@verizon.net> - 2012-05-16 07:18 -0400
                Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-16 16:30 -0700
                Re: Remving an element from Queue James Kuyper <jameskuyper@verizon.net> - 2012-05-17 09:09 -0400
                Re: Remving an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-17 11:48 -0700
                Re: Removing an element from Queue James Kuyper <jameskuyper@verizon.net> - 2012-05-17 15:38 -0400
                Re: Removing an element from Queue Barry Schwarz <schwarzb@dqel.com> - 2012-05-17 15:21 -0700
                Re: Removing an element from Queue James Kuyper <jameskuyper@verizon.net> - 2012-05-17 19:08 -0400
                Re: Removing an element from Queue Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-19 09:05 -0700
                Re: Removing an element from Queue lawrence.jones@siemens.com - 2012-05-20 15:10 -0400
                Re: Removing an element from Queue Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-21 09:00 -0700
                Re: Remving an element from Queue Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-19 08:49 -0700
                Re: Remving an element from Queue Tim Rentsch <txr@alumni.caltech.edu> - 2012-05-17 12:36 -0700
  Re: Remving an element from Queue nick_keighley_nospam@hotmail.com - 2012-05-08 05:09 -0700
    Re: Remving an element from Queue "BartC" <bc@freeuk.com> - 2012-05-08 14:03 +0100
      Re: Remving an element from Queue nick_keighley_nospam@hotmail.com - 2012-05-09 00:01 -0700
      Re: Remving an element from Queue nick_keighley_nospam@hotmail.com - 2012-05-09 00:03 -0700
        Re: Remving an element from Queue "BartC" <bc@freeuk.com> - 2012-05-09 10:37 +0100
          Re: Remving an element from Queue nick_keighley_nospam@hotmail.com - 2012-05-09 03:05 -0700
    Re: Remving an element from Queue arnuld <sunrise@invalid.address> - 2012-05-09 09:44 +0000
  Re: Remving an element from Queue Mark Bluemel <mark.bluemel@googlemail.com> - 2012-05-08 06:07 -0700
  Re: Remving an element from Queue Mark Bluemel <mark.bluemel@googlemail.com> - 2012-05-08 06:35 -0700
  Re: Remving an element from Queue Johann Klammer <klammerj@NOSPAM.a1.net> - 2012-05-08 20:50 +0200
  Re: Remving an element from Queue 88888 Dihedral <dihedral88888@googlemail.com> - 2012-05-11 00:39 -0700

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