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Re: Can I jump to a case inside a switch using goto?

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James Kuyper <jameskuyper@verizon.net> wrote:
> On 04/03/2014 02:36 AM, JohnF wrote:
>> Keith Thompson <kst-u@mib.org> wrote:
> ...
>>> You can always add labels as needed:
>>>    switch (...) {
>>>      case 0:
>>>        L0:      /* ... */ break;
>>>      case 1:
>>>        L1:      /* ... */ break;
>>>      /* ... */
>>>      default:
>>>        Default: /* ... */ break;
>>>      } /* --- end-of-switch() --- */
>>>    /* ... */
>>>    goto L0;
>>>    goto L1;
>>>    goto Default;
>>> But I'd really advise you to rethink your design.
>> 
>> Yeah, that's for sure. But just curious -- if one
>> of those goto's takes execution from outside the
>> switch's {...} to inside it, will the subsequent
>> break understand the scope, i.e., where the program
>> counter should go next? And is that behavior mandated
>> by standard?
> 
> "A break statement terminates execution of the smallest enclosing switch
> or iteration statement." (6.8.6.3p2) It doesn't matter how execution of
> the program reached the break statement, the only thing that matters is
> the location of the break statement.

Thanks, James. I hadn't been aware of that before.
But after posting, I realized I hadn't exactly asked
the complete question that bothered me. Consider the
following snippet,
  char label[100] = "printed during loop";
  int  nloop = 0;
  while ( 1 ) {
     int i = 0;
    entry_pt:
     i++;
     printf("%s: i=%d\n",label,i);
     if ( i >= 10 ) break;
     } /* --- continue --- */
  if ( ++nloop < 2 ) {
     strcpy(label,"printed after goto");
     goto entry_pt; }
Okay, so you know the question: what's the
value of i "printed after goto"? And what's the
general rule about that? And how portable is it?
Thanks,
-- 
John Forkosh  ( mailto:  j@f.com  where j=john and f=forkosh )

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Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-02 18:48 -0700
  Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-02 19:24 -0700
    Re: Can I jump to a case inside a switch using goto? <william@wilbur.25thandClement.com> - 2014-04-02 20:02 -0700
      Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-02 23:04 -0700
        Re: Can I jump to a case inside a switch using goto? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-03 07:51 +0000
          Re: Can I jump to a case inside a switch using goto? "BartC" <bc@freeuk.com> - 2014-04-03 09:39 +0100
            Re: Can I jump to a case inside a switch using goto? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-03 11:52 +0100
              Re: Can I jump to a case inside a switch using goto? "BartC" <bc@freeuk.com> - 2014-04-03 12:42 +0100
                Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-03 08:04 -0700
                Re: Can I jump to a case inside a switch using goto? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-04-03 15:59 +0000
              Re: Can I jump to a case inside a switch using goto? Lowell Gilbert <lgusenet@be-well.ilk.org> - 2014-04-03 14:24 -0400
                Re: Can I jump to a case inside a switch using goto? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-04 23:06 +0100
          Re: Can I jump to a case inside a switch using goto? Paul N <gw7rib@aol.com> - 2014-04-03 04:15 -0700
            Computed GOTOs (Was: Can I jump to a case inside a switch using goto?) gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-03 11:33 +0000
              Re: Computed GOTOs Richard <rgrdev_@gmail.com> - 2014-04-03 12:38 +0100
            Re: Can I jump to a case inside a switch using goto? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-04 23:22 +0100
        Re: Can I jump to a case inside a switch using goto? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-04-03 01:20 -0700
      Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-03 14:51 -0700
      Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-03 14:56 -0700
    Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-02 23:08 -0700
      Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-03 08:09 -0700
    Re: Can I jump to a case inside a switch using goto? JohnF <john@please.see.sig.for.email.com> - 2014-04-03 06:36 +0000
      Re: Can I jump to a case inside a switch using goto? James Kuyper <jameskuyper@verizon.net> - 2014-04-03 07:48 -0400
        Re: Can I jump to a case inside a switch using goto? JohnF <john@please.see.sig.for.email.com> - 2014-04-03 12:21 +0000
          Re: Can I jump to a case inside a switch using goto? James Kuyper <jameskuyper@verizon.net> - 2014-04-03 10:16 -0400
            Re: Can I jump to a case inside a switch using goto? Keith Thompson <kst-u@mib.org> - 2014-04-03 08:12 -0700
              Re: Can I jump to a case inside a switch using goto? James Kuyper <jameskuyper@verizon.net> - 2014-04-03 12:44 -0400
            Re: Can I jump to a case inside a switch using goto? JohnF <john@please.see.sig.for.email.com> - 2014-04-04 07:06 +0000
            Re: Can I jump to a case inside a switch using goto? Tim Rentsch <txr@alumni.caltech.edu> - 2014-04-14 16:38 -0700
  Re: Can I jump to a case inside a switch using goto? rivkaumiller@gmail.com - 2014-04-03 00:18 -0700
  Re: Can I jump to a case inside a switch using goto? "BartC" <bc@freeuk.com> - 2014-04-03 09:49 +0100

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