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Re: Variable-length arrays: should they be used at all?

From Phil Carmody <thefatphil_demunged@yahoo.co.uk>
Newsgroups comp.lang.c
Subject Re: Variable-length arrays: should they be used at all?
Date 2012-07-06 00:49 +0300
Organization A noiseless patient Spider
Message-ID <87pq89281a.fsf@bazspaz.fatphil.org> (permalink)
References <jscgum$lk6$1@speranza.aioe.org> <kfnvcic4nxi.fsf@x-alumni2.alumni.caltech.edu> <a51cldFtntU2@mid.individual.net> <kfn7gus473o.fsf@x-alumni2.alumni.caltech.edu>

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Tim Rentsch <txr@alumni.caltech.edu> writes:
>  For example:
> 
>     int
>     function_needing_a_VLA( int n ){
>         ...
>         double values[n][n];
>         if(  ! &values  ){
>             ... here we have detected an allocation failure,
...
> How would this be done?  Simple.  The compiler notices the check
> of the address of the VLA immediately after its declaration

This may have been covered elsethread (I have a lot to catch up on)
but was there any reason why you chose to decorate the test with 
an & operator? Why would 
    if(!values) {
not be an equally workable idiom? (I like the idea of there being
some idiom for this purpose, it does leave the language a bit 
fragile without it.)

Phil
-- 
> I'd argue that there is much evidence for the existence of a God.
Pics or it didn't happen.
-- Tom (/. uid 822)

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Thread

Variable-length arrays: should they be used at all? Rui Maciel <rui.maciel@gmail.com> - 2012-06-26 15:28 +0100
  Re: Variable-length arrays: should they be used at all? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-26 11:54 -0400
  Re: Variable-length arrays: should they be used at all? jacob navia <jacob@spamsink.net> - 2012-06-26 21:05 +0200
    Re: Variable-length arrays: should they be used at all? Rui Maciel <rui.maciel@gmail.com> - 2012-06-26 21:04 +0100
      Re: Variable-length arrays: should they be used at all? Keith Thompson <kst-u@mib.org> - 2012-06-26 13:09 -0700
        Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-06-27 17:50 +1200
          Re: Variable-length arrays: should they be used at all? jacob navia <jacob@spamsink.net> - 2012-06-27 07:57 +0200
            Re: Variable-length arrays: should they be used at all? gwowen <gwowen@gmail.com> - 2012-06-27 00:49 -0700
            Re: Variable-length arrays: should they be used at all? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-27 13:50 +0100
              Re: Variable-length arrays: should they be used at all? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-27 10:21 -0400
                Re: Variable-length arrays: should they be used at all? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-06-27 19:56 +0100
          Re: Variable-length arrays: should they be used at all? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-07-06 00:55 +0300
            Re: Variable-length arrays: should they be used at all? Andrew Cooper <amc96@cam.ac.uk> - 2012-07-05 23:37 +0100
              Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-06 16:53 -0700
            Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-07-06 18:26 +1200
              Re: Variable-length arrays: should they be used at all? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-07-07 17:37 +0300
                Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-07-08 08:03 +1200
            Re: Variable-length arrays: should they be used at all? gwowen <gwowen@gmail.com> - 2012-07-06 02:58 -0700
              Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-06 18:11 -0700
                Re: Variable-length arrays: should they be used at all? gwowen <gwowen@gmail.com> - 2012-07-09 02:33 -0700
                Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-09 11:35 -0700
                Re: Variable-length arrays: should they be used at all? Ike Naar <ike@iceland.freeshell.org> - 2012-07-09 22:33 +0000
                Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-10 10:52 -0700
                Re: Variable-length arrays: should they be used at all? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-07-09 12:03 -0700
                Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-07-10 09:19 +1200
        Re: Variable-length arrays: should they be used at all? Gareth Owen <gwowen@gmail.com> - 2012-06-27 07:25 +0100
    Re: Variable-length arrays: should they be used at all? jacob navia <jacob@spamsink.net> - 2012-06-27 07:10 +0200
      Re: Variable-length arrays: should they be used at all? jacob navia <jacob@spamsink.net> - 2012-06-27 20:48 +0200
  Re: Variable-length arrays: should they be used at all? Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-26 21:13 +0200
    Re: Variable-length arrays: should they be used at all? Rui Maciel <rui.maciel@gmail.com> - 2012-06-26 20:47 +0100
      Re: Variable-length arrays: should they be used at all? Keith Thompson <kst-u@mib.org> - 2012-06-26 13:05 -0700
      Re: Variable-length arrays: should they be used at all? David Resnick <lndresnick@gmail.com> - 2012-06-26 13:51 -0700
        Re: Variable-length arrays: should they be used at all? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-26 17:10 -0700
        Re: Variable-length arrays: should they be used at all? Gareth Owen <gwowen@gmail.com> - 2012-06-27 07:27 +0100
        Re: Variable-length arrays: should they be used at all? Rui Maciel <rui.maciel@gmail.com> - 2012-06-27 20:23 +0100
  Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-27 11:20 -0700
    Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-06-28 09:35 +1200
      Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-27 17:23 -0700
        Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-06-28 13:06 +1200
          Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-29 10:48 -0700
            Re: Variable-length arrays: should they be used at all? Ian Collins <ian-news@hotmail.com> - 2012-06-30 21:58 +1200
              Re: Variable-length arrays: should they be used at all? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-06-30 03:37 -0700
              Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-01 19:31 -0700
            Re: Variable-length arrays: should they be used at all? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-07-06 00:54 +0300
              Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-06 17:58 -0700
        Re: Variable-length arrays: should they be used at all? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-07-06 00:49 +0300
          Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-06 16:38 -0700
            Re: Variable-length arrays: should they be used at all? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-07-07 18:00 +0300
              Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-07 12:40 -0700
                Re: Variable-length arrays: should they be used at all? pacman@kosh.dhis.org (Alan Curry) - 2012-07-08 02:54 +0000
                Re: Variable-length arrays: should they be used at all? jacob navia <jacob@spamsink.net> - 2012-07-08 13:33 +0200
                Re: Variable-length arrays: should they be used at all? pacman@kosh.dhis.org (Alan Curry) - 2012-07-08 22:18 +0000
                Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-09 10:57 -0700
                Re: Variable-length arrays: should they be used at all? pacman@kosh.dhis.org (Alan Curry) - 2012-07-09 21:38 +0000
                Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-10 11:12 -0700
                Re: Variable-length arrays: should they be used at all? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-08 11:28 -0700

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