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Re: Constants and undefined behavior

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  Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-13 12:02 +0000
    Re: Constants and undefined behavior ram@zedat.fu-berlin.de (Stefan Ram) - 2026-06-13 12:13 +0000
      Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-13 12:44 +0000
        Re: Constants and undefined behavior ram@zedat.fu-berlin.de (Stefan Ram) - 2026-06-14 17:22 +0000
          Re: Constants and undefined behavior scott@slp53.sl.home (Scott Lurndal) - 2026-06-14 21:24 +0000
            Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-15 17:52 +0000
    Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-13 18:32 +0200
      Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-14 14:33 +0000
        Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-14 22:02 +0200
          Re: Constants and undefined behavior Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-06-14 15:55 -0700
            Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-15 10:09 +0200
              Re: Constants and undefined behavior antispam@fricas.org (Waldek Hebisch) - 2026-06-15 10:43 +0000
                Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-15 16:01 +0200
                  Re: Constants and undefined behavior antispam@fricas.org (Waldek Hebisch) - 2026-06-15 17:57 +0000
                    Re: Constants and undefined behavior David Brown <david.brown@hesbynett.no> - 2026-06-16 10:10 +0200
                      Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-24 17:45 +0200
                        Re: Constants and undefined behavior "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-06-24 12:27 -0700
              Re: Constants and undefined behavior Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-24 16:58 +0200
          Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-15 19:26 +0000
        Re: Constants and undefined behavior James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-06-15 21:59 -0400
          Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-16 04:59 +0000
        Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-06-29 05:41 -0700
          Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-06-29 15:23 +0000
            Re: Constants and undefined behavior Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-08-15 07:36 -0700
              Re: Constants and undefined behavior cross@spitfire.i.gajendra.net (Dan Cross) - 2026-08-18 20:27 +0000

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#400077

In article <110qali$3q27m$1@dont-email.me>,
James Kuyper  <jameskuyper@alumni.caltech.edu> wrote:
>On 14/06/2026 16:33, Dan Cross wrote:
>...
>> Here's the problem that I have with this line of reasoning.  C
>> is a language that has considerable history; there was a large
>> body of C code written before the first standard was ever
>> created, in 1988; C was a teenager.  And it took many years for
>> decent quality ANSI C compilers to be ubiquitous.  C could
>> legally drink by then.
>> 
>> "Undefined Behavior", in C, in the manner usually discussed in
>> this newsgroup, was introduced with the first standard.  That
>> means that there is --- still --- a large body of software that
>> has "UB" that was put there before UB existed as a thing
>> programmers needed to worry about in C.
>
>"undefined behavior", defined as "behavior ... for which this
>international standard imposes no requirements" Was introduced by the
>first standard. However, before there was a standard there was K&R C,
>the closest thing they had to a standard. And though the phrase
>"undefined behavior" was not in use, there was "behavior for which K&R C
>imposes no requirements". In fact, there was a great deal more of it,
>since K&R C was not written as carefully and precisely as the first
>standard, so it left a great deal more behavior that was "undefined by
>omission of any relevant definition" than there was in the first standard.

I am guessing that there was supposed to be a point in there
somewhere, but I can't find it.

	- Dan C.

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#400284

cross@spitfire.i.gajendra.net (Dan Cross) writes:

[...]

> "Undefined Behavior", in C, in the manner usually discussed in
> this newsgroup, was introduced with the first standard.

The term but not the concept, which was there since the
early days of C -- at least since K&R in 1978, and very
likely earlier (I haven't reviewed any of the earlier
descriptions of the language).

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#400286

In article <86mrwd7c49.fsf@linuxsc.com>,
Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>
>[...]
>
>> "Undefined Behavior", in C, in the manner usually discussed in
>> this newsgroup, was introduced with the first standard.
>
>The term but not the concept, which was there since the
>early days of C -- at least since K&R in 1978, and very
>likely earlier (I haven't reviewed any of the earlier
>descriptions of the language).

How much time elapsed before your response?

If you cannot respond in a timely manner (read: within a week),
then please do not respond at all.

That said, not really.  I've read K&R, both editions, and the
first really doesn't define a concept that gives such supreme
latitude to the compiler.  They merely acknowledged that there
existed things for which they could not give a good behavioral
definition.  The way that UB is defined and used in 2026 was
absent in K&R in 1978.

	- Dan C.

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#401209

cross@spitfire.i.gajendra.net (Dan Cross) writes:

> In article <86mrwd7c49.fsf@linuxsc.com>,
> Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>
>> cross@spitfire.i.gajendra.net (Dan Cross) writes:
>>
>> [...]
>>
>>> "Undefined Behavior", in C, in the manner usually discussed in
>>> this newsgroup, was introduced with the first standard.
>>
>> The term but not the concept, which was there since the
>> early days of C -- at least since K&R in 1978, and very
>> likely earlier (I haven't reviewed any of the earlier
>> descriptions of the language).
>
> [...] not really.  I've read K&R, both editions, and the
> first really doesn't define a concept that gives such supreme
> latitude to the compiler.  [...]

I didn't say any term was defined, only that such a
concept is present in the writing.

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#401307

In article <86bjb35u2z.fsf@linuxsc.com>,
Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>cross@spitfire.i.gajendra.net (Dan Cross) writes:
>> In article <86mrwd7c49.fsf@linuxsc.com>,
>> Tim Rentsch  <tr.17687@z991.linuxsc.com> wrote:
>>> cross@spitfire.i.gajendra.net (Dan Cross) writes:
>>>
>>> [...]
>>>
>>>> "Undefined Behavior", in C, in the manner usually discussed in
>>>> this newsgroup, was introduced with the first standard.
>>>
>>> The term but not the concept, which was there since the
>>> early days of C -- at least since K&R in 1978, and very
>>> likely earlier (I haven't reviewed any of the earlier
>>> descriptions of the language).
>>
>> [...] not really.  I've read K&R, both editions, and the
>> first really doesn't define a concept that gives such supreme
>> latitude to the compiler.  [...]
>
>I didn't say any term was defined, only that such a
>concept is present in the writing.

How much time did you allow to lapse before responding to this
thread?  Please either respond promptly or not at all.

	- Dan C.

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