Re: C++ forcing unnecessary changes to C?

From	jacobnavia <jacob@jacob.remcomp.fr>
Newsgroups	comp.lang.c
Subject	Re: C++ forcing unnecessary changes to C?
Date	2016-11-26 00:38 +0100
Organization	A noiseless patient Spider
Message-ID	<o1ai07$cd4$1@dont-email.me> (permalink)
References	(3 earlier) <o0nc67$8dh$1@dont-email.me> <faf53chagnm148n9jr0dc1a459ucos4rg2@4ax.com> <o115k5$84f$1@dont-email.me> <ef0g3cpbude8eivf8ve31aeqdgecemjs61@4ax.com> <ln7f7rb8vr.fsf@kst-u.example.com>

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Le 25/11/2016 à 21:30, Keith Thompson a écrit :

> Falling off the end of *any* function without returning a value is not
> an error in C89/C90.  It's only attempting to use the result that has
> undefined behavior.  C99 and C11 keep that rule; a "return;" with no
> value is forbidden in a non-void function, but it's still legal (but a
> bad idea) to fall off the end.
>

It would be better that should be promoted to error. I have a warning 
when you forget to establish the return value of a non void function.

It would be better to promote that warning to an error. The code that 
does that is in general BROKEN, since any use of the return value of 
that function is a bomb that explodes into your software: the 
introduction of NOISE in the data stream. That noise is amplified (or 
not) by the position and importance of the usage of the noise in the 
software.

If the committee decided that the old behaviour is wrong, a lot of bugs 
in old C software would surface. It depends then, if the old C software 
is still being actively used for important stuff. All compilers would 
introduce a compatibility option, but the users of the software would be 
warned that the software has a real problem!

Old software is rarely used for unimportant stuff, and it would be much 
nicer for everyone that the old software is fixed too.

Thread

C++ forcing unnecessary changes to C? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 20:34 +0800
  Re: C++ forcing unnecessary changes to C? Thiago Adams <thiago.adams@gmail.com> - 2016-11-18 05:09 -0800
    Re: C++ forcing unnecessary changes to C? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 21:42 +0800
      Re: C++ forcing unnecessary changes to C? jameskuyper@verizon.net - 2016-11-18 11:14 -0800
    Re: C++ forcing unnecessary changes to C? jameskuyper@verizon.net - 2016-11-18 11:10 -0800
      Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-19 15:26 +0100
        Re: C++ forcing unnecessary changes to C? "James R. Kuyper" <jameskuyper@verizon.net> - 2016-11-19 10:09 -0500
          Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-20 13:47 +0100
      Re: C++ forcing unnecessary changes to C? Thiago Adams <thiago.adams@gmail.com> - 2016-11-21 03:25 -0800
        Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-21 14:15 +0100
          Re: C++ forcing unnecessary changes to C? Thiago Adams <thiago.adams@gmail.com> - 2016-11-21 05:39 -0800
  Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 14:26 +0100
    Re: C++ forcing unnecessary changes to C? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 21:41 +0800
      Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 15:20 +0100
        Re: conduct in comp.lang.c "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 22:23 +0800
  Re: C++ forcing unnecessary changes to C? Philipp Klaus Krause <pkk@spth.de> - 2016-11-18 15:16 +0100
    Re: C++ forcing unnecessary changes to C? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 22:20 +0800
      Re: C++ forcing unnecessary changes to C? jameskuyper@verizon.net - 2016-11-18 11:18 -0800
    Re: C++ forcing unnecessary changes to C? supercat@casperkitty.com - 2016-11-18 07:15 -0800
      Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 16:55 +0100
        Re: C++ forcing unnecessary changes to C? supercat@casperkitty.com - 2016-11-18 08:31 -0800
          Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 17:38 +0100
  Re: C++ forcing unnecessary changes to C? John Bode <jfbode1029@gmail.com> - 2016-11-18 07:09 -0800
    Re: C++ forcing unnecessary changes to C? Thiago Adams <thiago.adams@gmail.com> - 2016-11-18 07:22 -0800
      Re: C++ forcing unnecessary changes to C? Thiago Adams <thiago.adams@gmail.com> - 2016-11-18 07:31 -0800
        Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 17:04 +0100
  Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-18 16:37 +0100
    Re: C++ forcing unnecessary changes to C? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 23:53 +0800
    Re: C++ forcing unnecessary changes to C? supercat@casperkitty.com - 2016-11-18 08:00 -0800
      Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 17:34 +0100
      Re: C++ forcing unnecessary changes to C? Keith Thompson <kst-u@mib.org> - 2016-11-18 09:32 -0800
    Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-18 17:09 +0100
      Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-18 18:02 +0100
        Re: C++ forcing unnecessary changes to C? Robert Wessel <robertwessel2@yahoo.com> - 2016-11-21 03:26 -0600
          Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-22 11:11 +0100
            Re: C++ forcing unnecessary changes to C? jameskuyper@verizon.net - 2016-11-22 08:55 -0800
            Re: C++ forcing unnecessary changes to C? Robert Wessel <robertwessel2@yahoo.com> - 2016-11-25 03:25 -0600
              Re: C++ forcing unnecessary changes to C? supercat@casperkitty.com - 2016-11-25 10:00 -0800
              Re: C++ forcing unnecessary changes to C? Keith Thompson <kst-u@mib.org> - 2016-11-25 12:30 -0800
                Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-26 00:38 +0100
                Re: C++ forcing unnecessary changes to C? supercat@casperkitty.com - 2016-11-26 10:44 -0800
                Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-26 20:44 +0100
                Re: C++ forcing unnecessary changes to C? supercat@casperkitty.com - 2016-11-26 12:38 -0800
                Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-26 21:00 +0100
  Re: C++ forcing unnecessary changes to C? jameskuyper@verizon.net - 2016-11-18 11:04 -0800
    Re: [OT] discipline and obedience "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-19 22:53 +0800
    Re: C & C++ Committee "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-19 22:55 +0800
      Re: C & C++ Committee jameskuyper@verizon.net - 2016-11-19 08:02 -0800
        Re: C & C++ Committee "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-20 00:09 +0800
          Re: C & C++ Committee jameskuyper@verizon.net - 2016-11-19 08:35 -0800
            Re: C & C++ Committee fir <profesor.fir@gmail.com> - 2016-11-19 08:51 -0800
              Re: Do you write C programs? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-20 01:00 +0800
            Re: C & C++ Committee "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-20 00:59 +0800
  Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-22 11:14 +0100
    Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-22 12:05 +0100
      Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-22 14:51 +0100
        Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-22 15:50 +0100
          Re: C++ forcing unnecessary changes to C? BartC <bc@freeuk.com> - 2016-11-22 15:01 +0000
            Re: C++ forcing unnecessary changes to C? Keith Thompson <kst-u@mib.org> - 2016-11-22 08:58 -0800
              Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-22 18:08 +0100
              Re: C++ forcing unnecessary changes to C? BartC <bc@freeuk.com> - 2016-11-22 18:14 +0000
                Re: C++ forcing unnecessary changes to C? Ian Collins <ian-news@hotmail.com> - 2016-11-23 08:33 +1300
                Re: C++ forcing unnecessary changes to C? BartC <bc@freeuk.com> - 2016-11-22 19:42 +0000
                Re: C++ forcing unnecessary changes to C? Ian Collins <ian-news@hotmail.com> - 2016-11-23 08:51 +1300
                Re: C++ forcing unnecessary changes to C? Keith Thompson <kst-u@mib.org> - 2016-11-22 12:13 -0800
                Re: C++ forcing unnecessary changes to C? BartC <bc@freeuk.com> - 2016-11-22 21:35 +0000
                Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-23 00:47 +0100
                Re: C++ forcing unnecessary changes to C? Keith Thompson <kst-u@mib.org> - 2016-11-22 12:09 -0800
                Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-23 00:40 +0100
                Re: C++ forcing unnecessary changes to C? jacobnavia <jacob@jacob.remcomp.fr> - 2016-11-26 01:27 +0100
                Re: C++ forcing unnecessary changes to C? David Brown <david.brown@hesbynett.no> - 2016-11-26 01:48 +0100
              Re: C++ forcing unnecessary changes to C? Nathan Wagner <nw@hydaspes.if.org> - 2016-11-24 18:09 +0000

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